Agronomy

16 pages, 2854 KiB

Open AccessEditor’s ChoiceArticle

Evaluating Non-Composted Red Cotton Tree (Bombax ceiba) Sawdust Mixtures for Raising Okra (Abelmoschus esculentus (L.) Moench) in Pots

by Muhammad Yasin, Farhan Anwar, Hassan Noorani, Sher Muhammad, Athar Mahmood, Talha Javed, Baber Ali, Khadiga Alharbi, Ibrahim A. Saleh and Hashem A. Abu-Harirah

Agronomy 2023, 13(1), 97; https://doi.org/10.3390/agronomy13010097 - 28 Dec 2022

Cited by 11 | Viewed by 2230

Abstract

In modern agriculture, the substrate industry prefers porous materials for plants to provide water and nutrients in soilless cultivation. Composted sawdust is such a substrate. The sawdust industry is interested in avoiding composting sawdust because it is time and labor-consuming. The study objective [...] Read more.

In modern agriculture, the substrate industry prefers porous materials for plants to provide water and nutrients in soilless cultivation. Composted sawdust is such a substrate. The sawdust industry is interested in avoiding composting sawdust because it is time and labor-consuming. The study objective was to evaluate whether non-composted (fresh) Bombax ceiba (red cotton tree) sawdust with added nutrients could be an alternative to composted sawdust for okra production. The sawdust was mixed with nutrients in the form of banana peels (a potassium source), eggshells (a calcium source), and urea (a nitrogen source). We conducted two independent pot experiments. Treatments were viz.: T₁: non-fertilized 100% sandy clay loam soil (control) (vol/vol); T₂: non-composted 100% B. ceiba sawdust (vol/vol); T₃: non-composted 80% B. ceiba sawdust + 20% banana peels (vol/vol); T₄: non-composted 60% B. ceiba sawdust + 20% banana peels + 20% eggshells (vol/vol); T₅: non-composted 60% B. ceiba sawdust + 20% banana peels + 20% eggshells (vol/vol) + urea (@ 91 kg N ha⁻¹). In both experiments, the germination of okra seeds was unaffected by the sawdust mixtures. The phenological development of okra was significantly greater in non-fertilized clay loam soil than in any non-composted sawdust mixtures. Plant height, leaf relative water content, stability index of the membrane, root length, chlorophyll content index, root and shoot dry and fresh weight, stem diameter, and single leaf area of okra were lower in all non-composted B. ceiba sawdust mixtures compared to the control. In contrast to T₂, T₅ resulted in fewer days before the first flower developed, an increase in the number of pods plant⁻¹, length of pod plant⁻¹, the diameter of the pod, fresh and dry weight of pod plant⁻¹, and the seed numbers pod⁻¹. It is concluded that amending non-composted B. ceiba sawdust with banana peels, eggshells, and urea (T₅) enhanced its perspective as a growth medium for okra. Nonetheless, the amendments were unlikely to establish an adequate yield of okra, as was the case with non-fertilized sandy clay loam soil. Full article

(This article belongs to the Special Issue Composting as a Key Driver for Sustainable Agricultural Scenarios—Volume II)

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16 pages, 2619 KiB

Open AccessEditor’s ChoiceArticle

Field Performance of Disease-Free Plants of Ginger Produced by Tissue Culture and Agronomic, Cytological, and Molecular Characterization of the Morphological Variants

by Xiaoqin Zhao, Shuangying Yu, Yida Wang, Dongzhu Jiang, Yiming Zhang, Liu Hu, Yongxing Zhu, Qie Jia, Junliang Yin, Yiqing Liu and Xiaodong Cai

Agronomy 2023, 13(1), 74; https://doi.org/10.3390/agronomy13010074 - 26 Dec 2022

Cited by 4 | Viewed by 3675

Abstract

Ginger (Zingiber officinale Rosc.) is an important spice crop valued for its flavored and medical properties. It is susceptible to soil-borne diseases, which can cause considerable economic loss to growers. In vitro culture is feasible for the propagation of disease-free ginger plants, [...] Read more.

Ginger (Zingiber officinale Rosc.) is an important spice crop valued for its flavored and medical properties. It is susceptible to soil-borne diseases, which can cause considerable economic loss to growers. In vitro culture is feasible for the propagation of disease-free ginger plants, but has several disadvantages when producing seed rhizomes that can be commercially used, such as long cultivation cycles (usually 2–3 years) and occurrence of somaclonal variation. In this study, dynamic changes in the morphological characteristics of in vitro-propagated disease-free plants of ‘Wuling’ ginger were evaluated by continuous observation and measurement at 30-day intervals, and morphological variants were screened and characterized by agronomic, cytological, and molecular analysis at harvest. Results showed that the plants grew rapidly within 120 days after planting, and the most active growth period was from 60 to 120 days. Eight plants with clear and stable morphological differences were screened out from approximately 2000 plants grown in the field, and they could be classified into two groups (VT1 and VT2) based on tiller number, plant height, leaf color, and leaf shape. By flow cytometry analysis and chromosome counting, the VT1 was confirmed to be diploid, with the shortest plant height, the largest number of tillers and rhizome knobs, and the smallest tiller diameter and rhizome size among the three types of plants. The VT2 was mixoploid, consisting of diploid and tetraploid cells, with significantly reduced tiller number and rhizome knobs, significantly larger stomatal guard cells/apertures, and significantly lower stomatal density. SSR analysis detected DNA band profile changes in six out of the eight variants, including one plant of the VT1 and all the VT2 plants. The findings of this study might contribute to the commercial production of disease-free seed rhizomes in ginger, and the characterized somaclonal variants could provide useful germplasm resources for future breeding. Full article

(This article belongs to the Special Issue Advances in Plant Genetic Breeding and Molecular Biology)

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14 pages, 1010 KiB

Open AccessEditor’s ChoiceArticle

Early and Late Season Nutrient Stress Conditions: Impact on Cotton Productivity and Quality

by Solomon Amissah, Michael Baidoo, Benjamin K. Agyei, Godfred Ankomah, Roger A. Black, Calvin D. Perry, Stephanie Hollifield, Nana Yaw Kusi, Glendon H. Harris and Henry Y. Sintim

Agronomy 2023, 13(1), 64; https://doi.org/10.3390/agronomy13010064 - 25 Dec 2022

Cited by 4 | Viewed by 1596

Abstract

Modern cotton (Gossypium spp. L) cultivars are efficient in nutrient uptake and utilization, and thus, may potentially tolerate nutrient stress. Early- and late-season nutrient stress (E-stress and L-stress, respectively) effects on cotton productivity and quality were assessed under different production conditions in [...] Read more.

Modern cotton (Gossypium spp. L) cultivars are efficient in nutrient uptake and utilization, and thus, may potentially tolerate nutrient stress. Early- and late-season nutrient stress (E-stress and L-stress, respectively) effects on cotton productivity and quality were assessed under different production conditions in Camilla and Midville, GA, USA. The E-stress received no nutrient application in the early season, but the full rates were split-applied equally at the initiation of squares and the second week of bloom stages. The L-stress received 30–40% of the full nutrient rates only at the initial stage of planting. The effects of nutrient stress on cotton productivity and fiber quality were not consistent across the different production conditions. Compared to the full nutrient rate, the E-stress did not adversely impact cotton yield, but rather it improved the lint and cottonseed yields under one production condition by 17.5% and 19.3%, respectively. Averaged across all production conditions, the L-stress decreased the lint and cottonseed yields by 34.4% and 36.2%, respectively. The minimal effects of E-stress on cotton suggest nutrient rates at the early season could be reduced and more tailored rates, informed by soil and plant tissue analyses, applied shortly before the reproductive phase. Full article

(This article belongs to the Special Issue Crop Nutrient Requirements and Advanced Fertilizer Management Strategies)

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18 pages, 14611 KiB

Open AccessEditor’s ChoiceReview

Bean Common Mosaic Disease: Etiology, Resistance Resource, and Future Prospects

by Muning Tang and Xue Feng

Agronomy 2023, 13(1), 58; https://doi.org/10.3390/agronomy13010058 - 24 Dec 2022

Cited by 7 | Viewed by 5494

Abstract

Bean common mosaic disease is one of the most destructive diseases of the common bean, which is one of the most important legumes worldwide. It is caused by two closely related potyviruses: bean common mosaic virus (BCMV) and bean common mosaic necrosis virus [...] Read more.

Bean common mosaic disease is one of the most destructive diseases of the common bean, which is one of the most important legumes worldwide. It is caused by two closely related potyviruses: bean common mosaic virus (BCMV) and bean common mosaic necrosis virus (BCMNV). Both viruses have spread to all the common bean-growing areas worldwide and have become a major challenge in bean production. In this review, we summarized the biology and diversity of BCMV and BCMNV, discussed the current knowledge on the resistance genes of BCMV, and finally pointed out the future prospects for the control of bean common mosaic disease. Full article

(This article belongs to the Special Issue Genetic and Molecular Basis of Plant Resistance to Viruses)

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16 pages, 1217 KiB

Open AccessEditor’s ChoiceArticle

Post-Tin-Mining Agricultural Soil Regeneration Using Local Resources, Reduces Drought Stress and Increases Crop Production on Bangka Island, Indonesia

by Rizki Maftukhah, Rosana M. Kral, Axel Mentler, Ngadisih Ngadisih, Murtiningrum Murtiningrum, Katharina M. Keiblinger, Michael Gartner and Rebecca Hood-Nowotny

Agronomy 2023, 13(1), 50; https://doi.org/10.3390/agronomy13010050 - 23 Dec 2022

Cited by 2 | Viewed by 1869

Abstract

Mining severely affects ecosystems and threatens local food security. Remediation practices, however, are a viable way of reducing the negative impacts on post-mining lands. In this study we aim to improve crop yields and drought resistance on a post-tin-mining site located in Bangka [...] Read more.

Mining severely affects ecosystems and threatens local food security. Remediation practices, however, are a viable way of reducing the negative impacts on post-mining lands. In this study we aim to improve crop yields and drought resistance on a post-tin-mining site located in Bangka Island, Indonesia, with locally available resources. Plots with five different soil amendments: (1) dolomite; (2) compost; (3) charcoal; combinations of (4) charcoal + compost; and (5) charcoal + sawdust; and a control were established. An intercropping system with cassava and centrosema was employed, and yields were determined. Drought resistance was evaluated by carbon isotope discrimination (∆¹³C) from crop parts of cassava and centrosema’s shoot. Soil physicochemical properties were determined at harvesting time. Soil amendments significantly improved cassava and centrosema yields. In particular, the compost and combined (charcoal + compost) treatments enhanced centrosema yields (1.18 and 1.99 kg·plot⁻¹, respectively) and were related to higher nutrient availability. Similarly, compost, charcoal, and combined treatments showed positive effects on the cassava yield (0.15–0.16 kg·plant⁻¹) and a higher drought resistance in the charcoal treatment (∆¹³C= 21.48‰). Increased water-holding capacity (WHC) reduced the water deficiency and boosted yields of cassava and centrosema when the soil was treated with dual amendments (charcoal + compost). Charcoal, compost, and their combination turned out to be the most sustainable amendments in degraded post-mining tropical soils. Full article

(This article belongs to the Special Issue Innovative Strategies for Sustainable Agriculture and Restoration of Degraded Soils)

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15 pages, 4437 KiB

Open AccessEditor’s ChoiceArticle

Seasonal Changes Modulate the Rhizosphere of Desert Plant Species

by Maqshoof Ahmad, Zafar Iqbal, Bushra, Azhar Hussain, Muhammad Abdullah, Abed Alataway, Ahmed Z. Dewidar and Mohamed A. Mattar

Agronomy 2023, 13(1), 57; https://doi.org/10.3390/agronomy13010057 - 23 Dec 2022

Viewed by 1169

Abstract

Arid and semi-arid ecosystems are categorized as having degraded soils due to the limited availability of water and nutrients. The perennial shrubs in these regions have developed different ecological and physiological adaptations to cope with harsh conditions. The plant species vary in the [...] Read more.

Arid and semi-arid ecosystems are categorized as having degraded soils due to the limited availability of water and nutrients. The perennial shrubs in these regions have developed different ecological and physiological adaptations to cope with harsh conditions. The plant species vary in the chemical profile of their root exudates, which can induce variability in the microbial community in the rhizosphere. The present research has been conducted (i) to investigate the variation in composition, diversity, and structure of rhizosphere’s bacterial community of desert plants; (ii) to identify plant-specific effects on the rhizosphere microbial community structure; and (iii) to determine the influence of soil moisture on the rhizosphere’s microbial community and soil biological properties under stressful conditions. Ten desert plant species from the Cholistan desert were selected as test specimens. Bacterial communities from the rhizosphere of 10 plants of each species were explored. Soil samples were collected during monsoon (June–August) and dry months (March–May). Microbial community structure analyses were carried out through 16S rRNA sequencing by targeting V3 and V4 regions. Among tested plant species, the rhizosphere of Leptadenia pyrotechnica (S6 vs. S16), Aerva javanica (Burm. f.) Juss. ex Schult (S9 vs. S19), and Vachellia jacquemontii (Benth.) (S10 vs. S20) had greater microbial diversity in both seasons. Higher levels of microbial communities were found during monsoon season. Furthermore, Gammaproteobacteria were abundant in the rhizospheres of all studied plants during the monsoon season. In contrast, the rhizosphere was abundant with unidentified_Actinobacteria during the dry season. The rhizospheric soil was further analyzed for biological properties. The maximum microbial biomass carbon (165 mg kg^–1) and microbial biomass nitrogen (6.7 mg kg^–1) were found in the rhizosphere of Vachellia jacquemontii (Benth.) Benth during monsoon season. However, a minimum of microbial biomass carbon (119 mg kg^–1) and microbial biomass nitrogen (4.2 mg kg^–1) were found in the rhizosphere of Cleome pallida Kotschy during dry seasons. The diversified microbial community structure and biological properties enable desert plants to cope with adverse climate conditions. Full article

(This article belongs to the Section Soil and Plant Nutrition)

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20 pages, 839 KiB

Open AccessEditor’s ChoiceArticle

Impacts of Biochar on Trifolium incarnatum and Lolium multiflorum: Soil Nutrient Retention and Loss in Sandy Loam Amended with Dairy Manure

by Cosette B. Taggart, James P. Muir, Jeff A. Brady, Eunsung Kan, Adam B. Mitchell and Olabiyi Obayomi

Agronomy 2023, 13(1), 26; https://doi.org/10.3390/agronomy13010026 - 22 Dec 2022

Cited by 5 | Viewed by 1675

Abstract

Biochar has many potential benefits in agroecosystems such as increasing productivity of crops and modifying soil nutrient content. Biochar is sourced from many waste materials which could easily and sustainably remedy current challenges in concentrated agricultural operations that use manure-based fertilizers. However, relatively [...] Read more.

Biochar has many potential benefits in agroecosystems such as increasing productivity of crops and modifying soil nutrient content. Biochar is sourced from many waste materials which could easily and sustainably remedy current challenges in concentrated agricultural operations that use manure-based fertilizers. However, relatively little is known about its effects on forage species in conjunction with manure or biochar enriched with manure effluent. Our objective was to look at the effect of biochar and dairy effluent soil amendments on a forage legume and a grass. In this study, sandy loam soil was amended with a variety of biochar (BC) in a greenhouse setting. Factors included (1) BC type; (2) BC loading percentage; (3) effluent saturation of BC; and (4) forage inclusion. The study was repeated twice: once with Trifolium incarnatum and once with Lolium multiflorum. Plant material was assayed for biomass (BM) and C and N content. Soil was assayed for nutrient content and micronutrients. Data were not normally distributed and were consequently analyzed for variance using non-parametric methods in R. Overall, T. incarnatum showed a very strong negative (p ≤ 0.05) impact associated with increasing loading percentages of blend and manure BC on herbage BM, while effluent saturation showed no effect (p > 0.05). In contrast, L. multiflorum showed a strong (p ≤ 0.05) positive impact of increasing loading percentages of saturated wood, blend, and manure BC on herbage BM. BC impact on soil nutrients and forage varied greatly depending on type of BC, loading percentage, and forage species included. Results indicated the importance of BC properties and rates, as well as forage species for nutrient tolerances when choosing a BC amendment and loading rate. Full article

(This article belongs to the Collection Agro-Ecology for Grassland-Based Farming Systems)

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27 pages, 2686 KiB

Open AccessEditor’s ChoiceReview

Soil Nematodes as a Means of Conservation of Soil Predatory Mites for Biocontrol

by Diana Rueda-Ramírez, Eric Palevsky and Liliane Ruess

Agronomy 2023, 13(1), 32; https://doi.org/10.3390/agronomy13010032 - 22 Dec 2022

Cited by 6 | Viewed by 4497

Abstract

Numerous lab and field studies have reported the potential of soil predatory mites for the biological control of plant-parasitic nematodes and arthropods pests. Most of these studies have utilized biocontrol agents in augmentative releases, essentially controlling the pest with the released predators. While [...] Read more.

Numerous lab and field studies have reported the potential of soil predatory mites for the biological control of plant-parasitic nematodes and arthropods pests. Most of these studies have utilized biocontrol agents in augmentative releases, essentially controlling the pest with the released predators. While this may be a valid approach, we hypothesize that conservation of soil mite predators with available, suitable, and accessible free-living nematodes as prey, will provide better agricultural ecosystem performance and long-range sustainability. In this manuscript, we review the relevant studies on soil predatory mite–nematode interactions and highlight their potential for conservation biological control of soil-borne pests. Additionally, we emphasize the importance of implementing environmentally sound soil management practices for the sustainability and conservation of functional soil food webs. Full article

(This article belongs to the Special Issue Nematodes: Drivers of Agricultural Ecosystem Performance)

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14 pages, 282 KiB

Open AccessEditor’s ChoiceArticle

Energy Efficiency of Oat:Pea Intercrops Affected by Sowing Ratio and Nitrogen Fertilization

by Gerhard Moitzi, Helmut Wagentristl, Hans-Peter Kaul, Jaroslav Bernas and Reinhard W. Neugschwandtner

Agronomy 2023, 13(1), 42; https://doi.org/10.3390/agronomy13010042 - 22 Dec 2022

Cited by 1 | Viewed by 1160

Abstract

This study analyzed energy input (direct and indirect), energy output, net-energy output, energy use efficiency, energy intensity, and the energy productivity of oat:pea intercrops as affected by sowing ratio (oat:pea (%:%): 100:0, 75:25, 50:50, 25:75, 0:100) and nitrogen (N) fertilization (0, 60, 120 [...] Read more.

This study analyzed energy input (direct and indirect), energy output, net-energy output, energy use efficiency, energy intensity, and the energy productivity of oat:pea intercrops as affected by sowing ratio (oat:pea (%:%): 100:0, 75:25, 50:50, 25:75, 0:100) and nitrogen (N) fertilization (0, 60, 120 kg N ha⁻¹). The two year field experiment was conducted on a calcaric Chernozem soil in the north-western part of the Pannonian Basin. The results for grain yield showed that pure stands of oat and pea had a higher energy use efficiency and energy intensity than intercrops, indicating that pure stands used the growing factors more efficiently than intercrops. The energy use efficiency was higher in pure pea than pure oat. The energy productivity for the above-ground biomass production was much more affected by the factor N fertilization than by the factor sowing ratio. The highest energy productivity of grain N yield and above-ground biomass N yield was achieved in pure pea stands (0:100). N in plant residues of the zero N fertilization variant required 68% lower technical energy than N from mineral fertilizer. The sowing rate of the intercrops is a management tool to trade-off between the benefits of the in-field biodiversity and energy efficiency. Full article

(This article belongs to the Special Issue Crop Productivity and Energy Balance in Large-Scale Fields)

25 pages, 2720 KiB

Open AccessEditor’s ChoiceArticle

Assessing the Relative Importance of Climatic and Hydrological Factors in Controlling Sap Flow Rates for a Riparian Mixed Stand

by Lucy Reading, Nelson Corbett, Jacinta Holloway-Brown and Laura Bellis

Agronomy 2023, 13(1), 8; https://doi.org/10.3390/agronomy13010008 - 21 Dec 2022

Viewed by 1350

Abstract

Evapotranspiration by phreatophytes in riparian zones makes up a large component of the water balance. However, our understanding of the relative importance of controlling factors such as climatic conditions, species type, depth to groundwater and distance to surface water in riparian zones remains [...] Read more.

Evapotranspiration by phreatophytes in riparian zones makes up a large component of the water balance. However, our understanding of the relative importance of controlling factors such as climatic conditions, species type, depth to groundwater and distance to surface water in riparian zones remains a significant knowledge gap. A field experiment was conducted in an irrigated catchment in North Queensland, Australia, to investigate the factors controlling evapotranspiration by groundwater dependent trees. The sap flow of four tree species was measured, along with soil moisture, groundwater levels and local climatic conditions. The relative influence of species, hydrologic and climate factors, and measured variables were investigated with two non-parametric methods: random forest and Principal Component Analysis (PCA). Field monitoring data revealed differences in sap flow rates and diurnal sap flow trends between species. Distance from surface water explained the most variance in sap flow rates, followed by depth to groundwater and species, based on random forest modeling. The sap flow rates for some of the Eucalyptus tessellaris trees at this site reduced as groundwater levels declined. Overall, results demonstrate the value that can be gained from applying non-parametric methods, such as random forest and PCA, to investigate the relative importance of the factors influencing evapotranspiration. Full article

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16 pages, 3156 KiB

Open AccessEditor’s ChoiceArticle

Multilocation Evaluation of Virginia and Runner -Type Peanut Cultivars for Yield and Grade in Virginia–Carolina Region

by Naveen Kumar, David C. Haak, Jeffrey C. Dunne and Maria Balota

Agronomy 2022, 12(12), 3206; https://doi.org/10.3390/agronomy12123206 - 16 Dec 2022

Cited by 1 | Viewed by 1404

Abstract

The peanut is mostly grown in semi-arid tropical regions of the world, characterized by unpredictable rainfall amounts and distribution. Average annual precipitation in the Virginia–Carolina (VC) region is around 1300 mm; however, unpredictable distribution can result in significant periods of water deficit and [...] Read more.

The peanut is mostly grown in semi-arid tropical regions of the world, characterized by unpredictable rainfall amounts and distribution. Average annual precipitation in the Virginia–Carolina (VC) region is around 1300 mm; however, unpredictable distribution can result in significant periods of water deficit and subsequent reduction in yield and gross income. The development of new peanut cultivars with high yield and acceptable levels of yield stability across various water-availability scenarios is an important component of the peanut breeding program in Virginia and the Carolinas, where the large-seeded Virginia-type peanut is the predominantly grown market type. In addition, the simultaneous use of runner cultivars developed in the dryer southeastern region has been proposed as a practical solution to limited irrigation availability in the VC region. Still, the identification and adequate utilization of available commercial cultivars with the best combination of yield, drought tolerance, and gross income is more immediately beneficial to the peanut industry, yet this assessment has not been carried out to date. The aim of this study was to identify cultivars that maintain high yield and grade, therefore gross income, across a wide range of environmental conditions. We evaluated five commercially available Virginia and runner-type peanut cultivars for pod yield stability using multilocation trials over four years across 13 environments. Additive main effects and multiplicative interaction (AMMI) and different stability approaches were used to study genotype (G), environment (E), and their interaction (G × E) on pod yield. Pod yield stability was specifically assessed by using the Lin and Binn approach, Wricke’s ecovalence, Shukla’s stability, and the Finlay–Wilkinson approach. The combined analysis of variance showed highly significant effects (p ≤ 0.001) for genotypes, environments, and G × E for pod yield. The environments varied in yield (2840–8020 kg/ha). Bailey, Sullivan, and Wynne are Virginia-type cultivars. The grade factors SMK, SS, and TK changed with water regime within both market types. Among the runner cultivars, TUFRunner 297 presented high mean productivity; however, it showed specific adaptation to limited environmental conditions. Based on different stability approaches, this study concludes that Sullivan and Bailey are the most stable and adaptable cultivars across the testing environments, whereas Wynne exhibited specific adaptability to some environments. These findings have important implications for peanut cultivar recommendations in terms of meeting peanut industry standards for yield, grading quality, and breeding progress. Full article

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19 pages, 3132 KiB

Open AccessEditor’s ChoiceArticle

Seasonal Variation in Physiological Traits of Amazonian Coffea canephora Genotypes in Cultivation Systems with Contrasting Water Availability

by Aldo Max Custodio, Paulo Eduardo de Menezes Silva, Thiago Rodrigues dos Santos, Lucas Loram Lourenço, Roniel Geraldo Avila, Anderson Rodrigo da Silva, Fernando Higino de Lima e Silva, Marcelo Curitiba Espindula, Jairo Rafael Machado Dias and Fabiano Guimarães Silva

Agronomy 2022, 12(12), 3197; https://doi.org/10.3390/agronomy12123197 - 16 Dec 2022

Cited by 1 | Viewed by 1356

Abstract

Climate variation throughout the year affects photosynthesis and other physiological processes correlated with plant development and yield. This study aimed to evaluate the changes in the physiological attributes of Coffea canephora genotypes over the year in the Brazilian Amazon and assess their relationship [...] Read more.

Climate variation throughout the year affects photosynthesis and other physiological processes correlated with plant development and yield. This study aimed to evaluate the changes in the physiological attributes of Coffea canephora genotypes over the year in the Brazilian Amazon and assess their relationship with crop yield. The experiment was carried out in three cultivation systems with three genotypes. The evaluations were carried out in four periods: the peak of the dry season (S1); the beginning of the rainy season (S2); the peak of the rainy season (S3); and the beginning of the dry season (S4). A dataset of gas exchange, pigment indices, chlorophyll fluorescence, branch growth, and coffee yield was obtained. The group of gas exchange variables was the main contributor to treatment discrimination and was most affected by seasons. As expected, the values of g_s, E, and A were significantly lower in S1, while the values of VPD_Leaf-ar, T_Leaf, and IWUE were significantly higher. Our results demonstrate that climatic seasonality affects the photosynthesis of Amazonian Robustas coffee, even under irrigated conditions, particularly in response to increased VPD. The physiological variables analyzed at the leaf level, even in different periods, did not explain the differences in the yield of C. canephora. Full article

(This article belongs to the Topic Plant Ecophysiology)

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18 pages, 28562 KiB

Open AccessEditor’s ChoiceArticle

In-Season Prediction of Corn Grain Yield through PlanetScope and Sentinel-2 Images

by Fenling Li, Yuxin Miao, Xiaokai Chen, Zhitong Sun, Kirk Stueve and Fei Yuan

Agronomy 2022, 12(12), 3176; https://doi.org/10.3390/agronomy12123176 - 15 Dec 2022

Cited by 7 | Viewed by 1955

Abstract

Crop growth and yield monitoring are essential for food security and agricultural economic return prediction. Remote sensing is an efficient technique for measuring growing season crop canopies and providing information on the spatial variability of crop yields. In this study, ten vegetation indices [...] Read more.

Crop growth and yield monitoring are essential for food security and agricultural economic return prediction. Remote sensing is an efficient technique for measuring growing season crop canopies and providing information on the spatial variability of crop yields. In this study, ten vegetation indices (VIs) derived from time series PlanetScope and Sentinel-2 images were used to investigate the potential to estimate corn grain yield with different regression methods. A field-scale spatial crop yield prediction model was developed and used to produce yield maps depicting spatial variability in the field. Results from this study clearly showed that high-resolution PlanetScope satellite data could be used to detect the corn yield variability at field level, which could explain 15% more variability than Sentinel-2A data at the same spatial resolution of 10 m. Comparison of the model performance and variable importance measure between models illustrated satisfactory results for assessing corn productivity with VIs. The green chlorophyll vegetation index (GCVI) values consistently produced the highest correlations with corn yield, accounting for 72% of the observed spatial variation in corn yield. More reliable quantitative yield estimation could be made using a multi-linear stepwise regression (MSR) method with multiple VIs. Good agreement between observed and predicted yield was achieved with the coefficient of determination value being 0.81 at 86 days after seeding. The results would help farmers and decision-makers generate predicted yield maps, identify crop yield variability, and make further crop management practices timely. Full article

(This article belongs to the Special Issue Crop Yield Estimation through Remote Sensing Data)

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17 pages, 1404 KiB

Open AccessEditor’s ChoiceReview

Potential of Omics to Control Diseases and Pests in the Coconut Tree

by Miguel Tzec-Simá, Jean Wildort Félix, María Granados-Alegría, Mónica Aparicio-Ortiz, Dilery Juárez-Monroy, Damian Mayo-Ruiz, Saraí Vivas-López, Rufino Gómez-Tah, Blondy Canto-Canché, Maxim V. Berezovski and Ignacio Islas-Flores

Agronomy 2022, 12(12), 3164; https://doi.org/10.3390/agronomy12123164 - 14 Dec 2022

Cited by 4 | Viewed by 7996

Abstract

The coconut palm (Cocos nucifera L.) is a common crop in pantropical areas facing various challenges, one of them being the control of diseases and pests. Diseases such as bud rot caused by Phytophthora palmivora, lethal yellowing caused by phytoplasmas of [...] Read more.

The coconut palm (Cocos nucifera L.) is a common crop in pantropical areas facing various challenges, one of them being the control of diseases and pests. Diseases such as bud rot caused by Phytophthora palmivora, lethal yellowing caused by phytoplasmas of the types 16SrIV-A, 16SrIV-D or 16SrIV-E, among others, and pests like the coconut palm weevil, Rhynchophorus vulneratus (Coleoptera: Curculionidae), and the horned beetle, Oryctes rhinocerus (Coleoptera: Scarabaeidae), are controlled by applying pesticides, pheromones and cultural control. These practices do not guarantee eradication since some causal agents have become resistant or are imbedded in infected tissues making them difficult to eradicate. This review condenses the current genomics, transcriptomics, proteomics and metabolomics studies which are being conducted with the aim of understanding the pathosystems associated with the coconut palm, highlighting the findings generated by omics studies that may become future targets for the control of diseases and pests in the coconut crop. Full article

(This article belongs to the Special Issue Research Progress on Pathogenicity of Fungus in Crop)

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14 pages, 2980 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Remediation of Pasture Dieback Using Plant Growth Promotant

by Maria M. Whitton, Xipeng Ren, Sung J. Yu, Tieneke Trotter, Dragana Stanley and Yadav S. Bajagai

Agronomy 2022, 12(12), 3153; https://doi.org/10.3390/agronomy12123153 - 12 Dec 2022

Cited by 4 | Viewed by 1847

Abstract

Pasture dieback is a syndrome of unknown cause affecting grasses in Australia, creating significant economic losses to farmers by reducing available livestock feed and paddock carrying capacity. RC3 is a commercial plant growth stimulant tri-sodium salt of trimercapto-S-triazine (TMT) and potassium humate as [...] Read more.

Pasture dieback is a syndrome of unknown cause affecting grasses in Australia, creating significant economic losses to farmers by reducing available livestock feed and paddock carrying capacity. RC3 is a commercial plant growth stimulant tri-sodium salt of trimercapto-S-triazine (TMT) and potassium humate as active ingredients. TMT is commonly used for soil and wastewater remediation by capturing and binding heavy metals, while potassium humate is an organic compound used as a plant growth promoter. We investigated the ability of RC3 to restore soil health and productivity under pasture dieback conditions. RC3 was applied on pasture dieback affected paddock replicate plots once, at a rate of 4 mL/m², and soil core samples were taken weekly to analyse microbial communities. Plants were collected regularly to measure dry matter and plant morphometrics. Twenty weeks after a single application, dry matter increased in RC3 plots by 900 kg/ha compared to control plots, and at week 48, eleven months after the single application, RC3 plots showed a trend of more grass and dicot species than the control. Morphometric measures suggest minor improvements in dicotyledon plants. Alpha diversity did not change with the application of RC3. Temporal correlation analysis shows that RC3 steadily reduced the presence of genera predominant in poor soils and with extreme environmental conditions over time and prevented the decline of beneficial genera, such as Marmoricola, Actinomadura, Dactylosporangium, and mle1-7. Full article

(This article belongs to the Section Grassland and Pasture Science)

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20 pages, 1662 KiB

Open AccessEditor’s ChoiceArticle

Evaluation of Anaerobic Soil Disinfestation for Environmentally Sustainable Weed Management

by Ram B. Khadka, Andres D. Sanabria-Velazquez, John Cardina and Sally A. Miller

Agronomy 2022, 12(12), 3147; https://doi.org/10.3390/agronomy12123147 - 12 Dec 2022

Cited by 2 | Viewed by 2255

Abstract

In anaerobic soil disinfestation (ASD), soil amended with a carbon source undergoes anaerobic conditions accompanied by changes in microbial community composition and an increase in the concentration of organic acids, primarily acetic and butyric acids, and gases that are deleterious to plant pathogens, [...] Read more.

In anaerobic soil disinfestation (ASD), soil amended with a carbon source undergoes anaerobic conditions accompanied by changes in microbial community composition and an increase in the concentration of organic acids, primarily acetic and butyric acids, and gases that are deleterious to plant pathogens, insects, and potentially to weeds. The purpose of this study was to explore the efficacy of ASD with different carbon sources on inactivation of propagules of a variety of weed species. Germination and viability of propagules of common lambsquarters (Chenopodium album L.), black nightshade (Solanum nigrum L.), yellow nutsedge (Cyperus esculentus L.), common pokeweed (Phytolacca decandra L.), barnyardgrass (Echinochloa crus-galli L.), dandelion (Taraxacum officinale (Weber)), and redroot pigweed (Amaranthus retroflexus L.) were tested using different rates of four carbon sources: molasses, wheat bran, mustard greens biomass, and raw chicken manure. Wheat bran was the most effective carbon source for inactivation of all weed propagules, followed by molasses and mustard greens biomass. Carbon sources were mixed with soil, which was irrigated to saturation and covered with plastic to promote anaerobic conditions for three weeks. Chicken manure inactivated all the tested species except A. retroflexus compared to the anaerobic control. Rates of carbon sources applied in soil were weakly but significantly correlated (r > 0.42 and p < 0.04) with weed seed mortality or germination inhibition (E. crus-galli) for all the tested carbon sources and weed species except for chicken manure for C. album, A. retroflexus, and S. nigrum. Laboratory tests to confirm organic acid toxicity showed that 1000 µL L⁻¹ acetic plus 1000 µL L⁻¹ butyric acids for at least 60 h inhibited of sprouting of C. esculentus tubers and E. crusgalli seeds, whereas 120 h or exposure was required to inhibit C. album seed germination. Anaerobic soil disinfestation effectively suppressed weed seed germination and viability when wheat bran, molasses and mustard greens biomass were used as carbon sources. This approach could be adopted for weed management in organic systems or any farming system where priority is given to environmentally sustainable practices. Full article

(This article belongs to the Special Issue Anaerobic Soil Disinfestation: A Tool for Non-Fumigant-Based Integrated Soil-Borne Disease and Pest Management)

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18 pages, 1454 KiB

Open AccessEditor’s ChoiceArticle

Allelic Complementation in Hybrid Superiority of Popcorn to Multiple Foliar Diseases

by Divino Rosa dos Santos Junior, Rodrigo Moreira Ribeiro, Antônio Teixeira do Amaral Junior, Marcelo Vivas, Julio Cesar Gadice Saluce, Jhean Torres Leite, Rosimeire Barboza Bispo, Valter Jário de Lima, Danielle Leal Lamego, Kevelin Barbosa Xavier, Kátia Fabiane Medeiros Schmitt, Samuel Henrique Kamphorst, Flávia Nicácio Viana, Alexandre Pio Viana and Messias Gongaza Pereira

Agronomy 2022, 12(12), 3103; https://doi.org/10.3390/agronomy12123103 - 07 Dec 2022

Cited by 1 | Viewed by 1139

Abstract

Popcorn cultivation has been growing in and has positively affected the Brazilian economy. However, these crops are grown with genotypes susceptible to diseases, generating high losses. Thus, studies aimed at obtaining resistant genotypes are particularly interesting, as popcorn is susceptible to several pathogens. [...] Read more.

Popcorn cultivation has been growing in and has positively affected the Brazilian economy. However, these crops are grown with genotypes susceptible to diseases, generating high losses. Thus, studies aimed at obtaining resistant genotypes are particularly interesting, as popcorn is susceptible to several pathogens. The most efficient, environmentally correct, and economical method of disease control is using resistant cultivars. The present study aimed to evaluate the performance of inbred lines of popcorn and their respective testcross hybrids in terms of diseases caused by fungi. For this purpose, 15 S₇ inbred lines were crossed with five testers, four with a narrow genetic basis (inbred lines L270, L651, P1, and L70) and one with a broad genetic basis (open pollination variety PARA 172). The arrangement of treatments in incomplete blocks (lattice 10 × 10) with three replications was used. The testcross was efficient in the discrimination per se of the progenies and the testers. The inbred lines L685, L691, L696, and L684 and the PARA 172 tester showed potential resistance to P. polysora, B. maydis, and E. turcicum. The GT biplot method proved reliable in identifying efficient, responsive, and resistant inbred lines and revealing the hybrid 56 as the ideal genotype. Full article

(This article belongs to the Special Issue Research Progress on Pathogenicity of Fungus in Crop)

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22 pages, 4371 KiB

Open AccessEditor’s ChoiceArticle

Honey Bee Exposure to the Fungicide Propiconazole in Lowbush Blueberry Fields

by Francis Andrew Drummond

Agronomy 2022, 12(12), 3081; https://doi.org/10.3390/agronomy12123081 - 05 Dec 2022

Cited by 3 | Viewed by 1789

Abstract

The fungicide propiconazole is a commonly used fungicide in small fruit and tree fruit production in the U.S.A. In Maine wild blueberry production, it is used almost exclusively for mummy berry disease control. The goal of this study is to assess the risk [...] Read more.

The fungicide propiconazole is a commonly used fungicide in small fruit and tree fruit production in the U.S.A. In Maine wild blueberry production, it is used almost exclusively for mummy berry disease control. The goal of this study is to assess the risk of exposure to honey bee colonies deployed in wild blueberry fields for pollination. The study was conducted over a six-year period (2009–2014) in both the field and laboratory. Field surveys (2009–2011) measured the residues on blueberry flowers in 41 commercial fields across the blueberry growing region. A two-year study (2010–2011) determined the decay rate of propiconazole in blueberry fields after application. A laboratory study determined the contact LD₅₀ of propiconazole to honey bee workers (2013). A field exposure/effect study was conducted over three years (2011–2013). In this study, 8–18 previously unexposed colonies were randomly assigned to one of two treatments, (1) isolated fields that were treated prior to bloom with the fungicide, propiconazole, but no other pesticides, or (2) isolated fields that were not treated with propiconazole or any other pesticides. The measures taken to evaluate effects of exposure monitored each year were (1) estimation of the exposure to colonies, measured as residues on flowers, workers, and in pollen brought back to hives; (2) colony population size (workers and brood); (3) queen status and presence; (4) queen oviposition rate; (5) supersedure rate; (6) egg hatch success; (7) mortality of developing larvae and pupae; (8) royal jelly deposition in wax comb cells; (9) worker longevity; (10) foraging activity; (11) treated bloom repellency to foragers; (12) colony overwintering success; (13) worker hypopharyngeal gland acini size; and (14) pathogen and parasite incidence and intensity. The results of these experiments and surveys showed that the propiconazole contact LD₅₀ was 24,747 ppb. Residues of propiconazole were found to be commonly abundant on flowers in treated commercial fields after application with a mean concentration of 2083.8

\pm

851.3 (se). The decay of propiconazole to non-detectable levels took about 40 days after application. The three-year hive deployment study showed that residues in treated fields were detected on flowers, pollen, and worker bees, demonstrating that exposure to this fungicide occurs even though it is applied before bloom. Also in the hive deployment study, evidence of reduced colony populations, increased supersedure, decreased queen oviposition rate, increased pathogen or parasite incidence and intensity, and increased overwintering colony loss due to propiconazole exposure was not found. However, propiconazole exposed colonies exhibited reduced worker longevity (17.3%), hypertrophy of 5 d old nurse bee hypopharyngeal acini (8.3%), and a 3.5 h repellency of foragers to treated bloom. Full article

(This article belongs to the Special Issue Ecological Research on Crop Pollinators)

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22 pages, 6622 KiB

Open AccessEditor’s ChoiceArticle

The Expanded and Diversified Calmodulin-Binding Protein 60 (CBP60) Family in Rice (Oryza sativa L.) Is Conserved in Defense Responses against Pathogens

by Diksha Kumari, Bishun Deo Prasad, Sangita Sahni, Heather M. Nonhebel and Priti Krishna

Agronomy 2022, 12(12), 3060; https://doi.org/10.3390/agronomy12123060 - 03 Dec 2022

Cited by 3 | Viewed by 1635

Abstract

Plant disease management is key to sustainable production of staple food crops. Calcium (Ca²⁺) signal and phytohormones play critical roles in regulating plant defense responses against pathogens. The Ca²⁺ signals are sensed, decoded and transduced by calmodulin and other Ca [...] Read more.

Plant disease management is key to sustainable production of staple food crops. Calcium (Ca²⁺) signal and phytohormones play critical roles in regulating plant defense responses against pathogens. The Ca²⁺ signals are sensed, decoded and transduced by calmodulin and other Ca²⁺ -binding proteins, followed by interaction with and modulation of activities of target proteins such as calmodulin-binding proteins (CBPs). Members of the Arabidopsis CBP60 gene family, AtCBP60g and AtSARD1, have emerged as major regulators of immune responses. In this study, we identified a 15 member CBP60 gene family in rice (Oryza sativa) of which OsCBP60g-3, OsCBP60g-4, OsCBP60a and OsSARD-like1 genes were consistently upregulated in rice seedlings in response to infection with both fungal (Magnaporthe oryzae) and bacterial (Xanthomonas oryzae) pathogens as well as by salicylic acid (SA). OsCBP60g-4 and OsCBP60g-3 were induced maximally by SA and brassinosteroid (BR), respectively, and OsCBP60g-4 was expressed at 3-fold higher levels in the M. oryzae resistant rice genotype (IC-346004) as compared to the susceptible rice genotype (Rajendra Kasturi). The considerable expansion of the immunity clade and the up-regulation of several OsCBP60 genes in response to pathogens and defense hormones supports the importance of further investigating OsCBP60 genes as targets for increasing disease resistance in rice. Full article

(This article belongs to the Section Crop Breeding and Genetics)

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25 pages, 5550 KiB

Open AccessEditor’s ChoiceArticle

Foliar Application of Chitosan and Phosphorus Alleviate the Potato virus Y-Induced Resistance by Modulation of the Reactive Oxygen Species, Antioxidant Defense System Activity and Gene Expression in Potato

by Alshymaa Z. Al-Mokadem, Abd El-Aleem M. Alnaggar, Ahmed G. Mancy, Ahmed R. Sofy, Mahmoud R. Sofy, Abdel Kareem S. H. Mohamed, Mostafa M. A. Abou Ghazala, Khaled M. El-Zabalawy, Noura F. G. Salem, Mohamed E. Elnosary and Mona S. Agha

Agronomy 2022, 12(12), 3064; https://doi.org/10.3390/agronomy12123064 - 03 Dec 2022

Cited by 12 | Viewed by 2382

Abstract

Viruses pose a serious threat to the sustainable production of economically important crops around the world. In the past 20 years, potato virus Y (PVY) emerged as a relatively new and very serious problem in potatoes, even though it is the oldest known [...] Read more.

Viruses pose a serious threat to the sustainable production of economically important crops around the world. In the past 20 years, potato virus Y (PVY) emerged as a relatively new and very serious problem in potatoes, even though it is the oldest known plant virus. Multiple strains of the virus cause various symptoms on the leaves and tubers of potatoes, resulting in yield reduction and poor-quality tubers. Consequently, it would be very interesting to learn what causes systemic PVY resistance in plants. Natural compounds such as chitosan (CHT) and phosphorus have been developed as alternatives to chemical pesticides to manage crop diseases in recent years. In the current study, potato leaves were foliar-sprayed with chitosan and phosphorus to assess their ability to induce PVY resistance. Compared to untreated plants, the findings demonstrated a significant decrease in disease severity and PVY accumulation in plants for which CHT and P were applied. Every treatment includes significantly increased growth parameters, chlorophyll content, photosynthetic characteristics, osmoprotectants (glycine betaine, proline, and soluble sugar), non-enzymatic antioxidants (glutathione, phenols, and ascorbic acid), enzymatic antioxidants (peroxidase, superoxide dismutase, lipoxygenase, glutathione reductase, catalase, β-1,3 glucanase, and ascorbate peroxidase), phytohormones (gibberellic acid, indole acetic acid, jasmonic acid, and salicylic acid), and mineral content (phosphorus, nitrogen, and potassium), compared to infected plants. However, compared to PVY infection values, CHT and P treatments showed a significant decrease in malondialdehyde, DPPH, H₂O₂, O₂, OH, and abscisic acid levels. In addition, increased expression levels of some regulatory defense genes, including superoxide dismutase (SOD), ascorbic acid peroxidase (APX), relative pathogenesis-related 1 basic (PR-1b), and relative phenylalanine ammonia-lyase (PAL), were found in all treated plants, compared to PVY-infected plants. Conclusion: Phosphorus is the most effective treatment for alleviating virus infections. Full article

(This article belongs to the Special Issue Perspectives and Challenges for Sustainable Management of Fruit and Foliar Diseases)

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16 pages, 1633 KiB

Open AccessEditor’s ChoiceArticle

Winter Wheat Seeding Decisions for Improved Grain Yield and Yield Components

by Lawrence Aula, Amanda C. Easterly and Cody F. Creech

Agronomy 2022, 12(12), 3061; https://doi.org/10.3390/agronomy12123061 - 03 Dec 2022

Cited by 3 | Viewed by 1695

Abstract

The continual re-evaluation of agronomic practices is necessary to improve crop performance and sustainability of the production of winter wheat (Triticum aestivum L.), particularly as genetics and climate conditions change. Recommendations made about winter wheat planting dates, spacing, variety, and seed rates [...] Read more.

The continual re-evaluation of agronomic practices is necessary to improve crop performance and sustainability of the production of winter wheat (Triticum aestivum L.), particularly as genetics and climate conditions change. Recommendations made about winter wheat planting dates, spacing, variety, and seed rates under normal climatic conditions may not be suitable in current times with more climate variability. Our experiment investigated the effect of planting date (early, historic-optimum, and late), row spacing (19 and 25 cm), variety (Goodstreak, Robidoux, and Wesley), and seed rate (1.8, 2.1, 2.3, 2.4, 2.6, 2.8, 3.1, and 3.4 M seeds ha⁻¹) on winter wheat grain yield and yield components. The seeding rate was nested within row spacing in nested-factorial design. A nested-factorial treatment design was used with testing at several locations in Nebraska across two years. Variety had a substantial effect on winter wheat grain yield (p < 0.05). Variety also had a substantial interaction effect with planting date and row spacing 50% of the time (p ≤ 0.01). At Hemingford, for example, Wesley planted at 19 cm had 5.9% more yield when compared to Robidoux planted at 19 cm (5.5 Mg ha⁻¹). Similarly, biomass was influenced by variety across sites (p < 0.01), but a substantial interaction effect also occurred between planting date and variety at two of the three sites. Narrow row spacing (19 cm) led to significantly more tillers (6.9 M ha⁻¹) when planted with Goodstreak at two of the sites. While planting date by itself did not affect any of the responses evaluated, this research highlights the importance of comprehensive and holistic approaches to wheat production in the High Plains. Full article

(This article belongs to the Section Innovative Cropping Systems)

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19 pages, 3894 KiB

Open AccessEditor’s ChoiceReview

Plant Growth Promoting Filamentous Fungi and Their Application in the Fertilization of Pastures for Animal Consumption

by Rosalba Argumedo-Delira, Mario J. Gómez-Martínez and Jairo Mora-Delgado

Agronomy 2022, 12(12), 3033; https://doi.org/10.3390/agronomy12123033 - 30 Nov 2022

Cited by 6 | Viewed by 4402

Abstract

The diversity of fungi in different terrestrial and aquatic ecosystems has made it possible to explore their use as important tools in promoting plant growth and in managing plant diseases given their high potential to replace the use of synthetic chemical products (fertilizers [...] Read more.

The diversity of fungi in different terrestrial and aquatic ecosystems has made it possible to explore their use as important tools in promoting plant growth and in managing plant diseases given their high potential to replace the use of synthetic chemical products (fertilizers and pesticides). Therefore, this review compiles information on the use of filamentous fungi in promoting plant growth, highlighting the most studied fungal genera for this purpose, such as Trichoderma, Penicillum, and Aspergillus. In addition, information is compiled on the promotion of forage grass growth using filamentous fungi, which could be a sustainable and lower-cost alternative in producing pastures to help raise animals. Full article

(This article belongs to the Topic Biostimulants in Agriculture)

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13 pages, 3345 KiB

Open AccessEditor’s ChoiceArticle

Variation in the Antimicrobial Activity of Essential Oils from Cultivars of Lavandula angustifolia and L. × intermedia

by Magdalena Walasek-Janusz, Agnieszka Grzegorczyk, Daniel Zalewski, Anna Malm, Sylwia Gajcy and Robert Gruszecki

Agronomy 2022, 12(12), 2955; https://doi.org/10.3390/agronomy12122955 - 25 Nov 2022

Cited by 14 | Viewed by 1977

Abstract

The antimicrobial properties of essential oil from Lavandula sp. raise hopes related to its use in phytotherapy. This study aimed to evaluate the antimicrobial activity of essential oils from cultivars of L. angustifolia (‘Hidcote Blue Strain’, ‘Hidcote Blue’) and L. × intermedia (‘Phenomenal’, [...] Read more.

The antimicrobial properties of essential oil from Lavandula sp. raise hopes related to its use in phytotherapy. This study aimed to evaluate the antimicrobial activity of essential oils from cultivars of L. angustifolia (‘Hidcote Blue Strain’, ‘Hidcote Blue’) and L. × intermedia (‘Phenomenal’, ‘Grosso’) grown in central-eastern Poland, that is, at the border of the northern lavender cultivation range. The chemical composition of the essential oils was determined by GC/MS. Essential oil concentrations (20, 10, 5, 2.5, 1.25, 0.6, 0.3, 0.16, 0.08, and 0.04 mg/mL) were tested to determine the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) or minimum fungicidal concentration (MFC) towards ten strains of Gram-positive bacteria, five Gram-negative bacteria, and eight yeasts in vitro culture. Essential oils from the Lavendula cultivars showed antimicrobial activity against all microorganisms analysed. The yeasts were characterised by higher sensitivity to lavender oil compared to bacteria, while Gram-positive bacteria were more sensitive than Gram-negative bacteria. The lowest MIC values for bacteria and fungi were obtained for ‘Grosso’. Furthermore, the ‘Grosso’ oil showed the highest fungicidal activity, while the highest bactericidal activity was found in ‘Hidcote Blue’ and ‘Grosso’. Using Staphylococcus aureus as an example, it was shown that different bacterial strains of the same species show varying sensitivity to the essential oil. A higher oil content was noted for the cultivars L. × intermedia, especially for the ‘Phenomenal’. Linalyl acetate and linalool were the main components of the essential oil in all cultivars. However, in the ‘Grosso’ oil, a high content of terpinen-4-ol (18.08%) was also recorded. An analysis of the relationships between the content of the main components in the analysed essential oils and the antimicrobial activity of essential oils suggested that linalool and terpinen-4-ol were compounds potentially responsible for antimicrobial activity. The obtained results allow us to conclude that essential oil with significant antimicrobial activity can be obtained from Lavandula sp. plants harvested in the northern part of the cultivation range. Full article

(This article belongs to the Special Issue Chemical Diversity, Yield and Quality of Aromatic Plant)

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11 pages, 279 KiB

Open AccessEditor’s ChoiceArticle

Antagonistic Interactions between Dicamba and Glyphosate on Barnyardgrass (Echinochloa crus-galli) and Horseweed (Erigeron canadensis) Control

by Estefania G. Polli, Leandro H. S. Guimaraes, Jose H. S. de Sanctis and Greg Kruger

Agronomy 2022, 12(12), 2942; https://doi.org/10.3390/agronomy12122942 - 24 Nov 2022

Cited by 1 | Viewed by 1519

Abstract

Dicamba plus glyphosate (DpG) tank mixture has been widely adopted for broad-spectrum weed control. However, recent studies indicated antagonistic interactions between these herbicides. Furthermore, little is known about the effect of non-ammonium sulfate water conditioner (non-AMS WC) adjuvant on the activity of DpG [...] Read more.

Dicamba plus glyphosate (DpG) tank mixture has been widely adopted for broad-spectrum weed control. However, recent studies indicated antagonistic interactions between these herbicides. Furthermore, little is known about the effect of non-ammonium sulfate water conditioner (non-AMS WC) adjuvant on the activity of DpG tank mixture. Thus, the present study was elaborated to evaluate (1) the interaction of DpG tank mixtures combinations on barnyardgrass, and glyphosate-susceptible (GS) and -resistant (GR) horseweed control, and (2) the effect of non-ammonium sulfate water conditioner (non-AMS WC) on the interaction of those two herbicides on the aforementioned weed species. Greenhouse experiments were conducted in 2020 at the Pesticide Application Laboratory in North Platte, NE. Herbicide treatments were arranged in a two-level factorial design of six dicamba rates by six glyphosate rates for Study 1, and in a three-level factorial design of two adjuvant treatments (presence or not of non-AMS WC) by four dicamba rates by four glyphosate rates for Study 2. Both trials were conducted as randomized complete block designs with four replications and two runs. Antagonistic interactions were observed throughout DpG treatments in GS and GR horseweed. For instance, dicamba (560 g ae ha⁻¹) and glyphosate (1260 g ae ha⁻¹) resulted in 72% of GR horseweed biomass reduction, compared to 81% of estimated biomass reduction. For barnyardgrass, antagonistic interactions were only observed within the reduced glyphosate rates. The addition of non-AMS WC had no effect on DpG antagonism. However, it improved the barnyardgrass control by glyphosate. Full article

(This article belongs to the Special Issue Herbicides Toxicology and Weeds Herbicide-Resistant Mechanism)

14 pages, 2456 KiB

Open AccessEditor’s ChoiceArticle

Annual Ryegrass (Lolium rigidum), Wild Oats (Avena spp.) and Sowthistle (Sonchus oleraceus) Are the Most Commonly Occurring Weeds in New South Wales Cropping Fields

by John C. Broster, Allison J. Chambers, Leslie A. Weston and Michael J. Walsh

Agronomy 2022, 12(12), 2914; https://doi.org/10.3390/agronomy12122914 - 23 Nov 2022

Cited by 1 | Viewed by 1341

Abstract

Weeds are a major impediment to crop and pasture production and profitability in Australian farming systems, and knowledge of their occurrence is vital in devising weed management solutions. This study examined the relationships between weed and crop species from observations made during surveys [...] Read more.

Weeds are a major impediment to crop and pasture production and profitability in Australian farming systems, and knowledge of their occurrence is vital in devising weed management solutions. This study examined the relationships between weed and crop species from observations made during surveys of randomly selected fields in grain and/or pasture production. Between 2013 and 2017, 996 fields across New South Wales (NSW) were surveyed to record the occurrence and density of weed species. Annual ryegrass (Lolium rigidum) (69% of fields), wild oats (Avena spp.) (60%), and sowthistle (Sonchus oleraceus) (34%) were the most common species identified, with a total of 65 weed species recorded to be occurring in NSW cropping fields. Densities of occurring weeds were low, at one plant per square metre or less. Multiple species of wild oats were recorded, with their occurrence varying between survey regions; for example, Avena sterilis subsp. ludoviciana was more prevalent in the north and Avena fatua in the south. Differences in weed species occurrence were noted between this survey and those previously conducted in NSW, with marked increases in annual ryegrass and sowthistle, and this is attributed to the change in crop production practices between survey periods. The study of variable distribution patterns of weed species across cropping systems allows for informed decision-making regarding weed management research and development planning. Full article

(This article belongs to the Special Issue Weed Population Dynamics)

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18 pages, 3667 KiB

Open AccessEditor’s ChoiceArticle

Assessing Processing Waste from the Sea Urchin (Centrostephanus rodgersii) Fishery as an Organic Fertilizer

by Paolo Campus, Nigel D. Swarts, Craig Mundy, John P. Keane and Caleb Gardner

Agronomy 2022, 12(12), 2919; https://doi.org/10.3390/agronomy12122919 - 23 Nov 2022

Cited by 2 | Viewed by 3636

Abstract

The longspined sea urchin, Centrostephanus rodgersii, is a climate-driven pest species in south-eastern Australia. The harvest of this species is highly encouraged and in Tasmania, the existing fishery is expanding resulting in a large amount of waste that needs disposal. Research into [...] Read more.

The longspined sea urchin, Centrostephanus rodgersii, is a climate-driven pest species in south-eastern Australia. The harvest of this species is highly encouraged and in Tasmania, the existing fishery is expanding resulting in a large amount of waste that needs disposal. Research into use of waste products as inputs for organic or biodynamic farming systems can help reduce costs of disposal and keep the industry profitable; by sustaining or incrementing sea urchin harvest the industry can assist in their control. In the current study, urchin waste was dried and finely ground to a powder and applied to tomato plants in a greenhouse to examine the effect on growth and productivity. Urchin waste powder (UWP) had a mineral composition of Ca (40 g 100 g⁻¹), Mg (1.7 g 100 g⁻¹), P (0.03 g 100 g⁻¹), Fe (19.34 mg kg⁻¹) and B (38 mg kg⁻¹), a pH 8.06 in water and an Electrical Conductivity (EC) value of 7.64 dSm⁻¹. Seven different treatment rates of UWP (0.3%; 0.5%; 0.8%; 1%; 2%; 3%; 5%), were added to 10 replicate pots containing 4 kg nutrient-poor potting mix planted with tomato (Variety K1) seedlings. Plant growth, yield, quality attributes and mineral content of tomato were measured under UWP treatments with comparison against a Hoagland solution control. UWP influenced tomato growth and productivity proportional to the quantity applied, however, the Hoagland solution control had a significantly greater yield. Potting mix pH increased from 6.8 to 7 and higher available P was detected in potting mix receiving higher rates of UWP. No phytotoxic effects were detected. The highest UWP treatment matched the Hoagland control in fruit quality and nutritional composition. Processing waste from the sea urchin fishery has potential as organic fertiliser or amendment providing plant-available Ca and some microelements such as Boron. Full article

(This article belongs to the Special Issue Application of Organic Amendments in Agricultural Production)

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13 pages, 2026 KiB

Open AccessEditor’s ChoiceArticle

Effect of Date of Sowing and Spacing of Plants on Yield and Quality of Chamomile (Matricaria chamomilla L.) Grown in an Arid Environment

by Moti Lal Mehriya, Devendra Singh, Aman Verma, Shailendra Nath Saxena, Abed Alataway, Ahmed A. Al-Othman, Ahmed Z. Dewidar and Mohamed A. Mattar

Agronomy 2022, 12(12), 2912; https://doi.org/10.3390/agronomy12122912 - 22 Nov 2022

Cited by 2 | Viewed by 1799

Abstract

Little is known about how Indian farming practices affect German chamomile (Matricaria chamomilla L.). This study examines the effects of the sowing date and spacing of plants on flower productivity, essential oil concentration, and the composition of German chamomile grown in the [...] Read more.

Little is known about how Indian farming practices affect German chamomile (Matricaria chamomilla L.). This study examines the effects of the sowing date and spacing of plants on flower productivity, essential oil concentration, and the composition of German chamomile grown in the arid zone of Rajasthan, India. In a factorial randomized block design (FRBD), the treatments consisted of four sowing dates (15 and 25 October, 5 and 15 November) and three spacings of plants (20 × 10 cm, 30 × 10 cm, and 40 × 10 cm). The dried flower yield (Kg ha⁻¹), fresh flower yield (Kg ha⁻¹), and number of flowers per plant of chamomile crop were significantly affected by the varying spacing of plants and the date of sowing. The highest values for dry weight, fresh weight, and number of flowers were obtained from the second date of sowing (25 October) with 40 × 10 cm geometry. Likewise, the highest values for total oil (12.44%) and essential oil (0.94%) contents were also obtained from the D2P3 combination (D2—sowing date 25 October, P3—40 × 10 cm spacing of plants). GC/MS analyses of the samples showed that p-menth-1-en-4-ol, acetate, cis-alpha-farnesene, anethole+estragol, 1,4-cyclohexadiene,1-methyl-4-(1-methylethyl)- and 3,6-dihydro-4-(4-methyl-3-pentenyl)-1,2-dithiin were the main identified compounds in the essential oil of chamomile fresh flowers. The treatments altered the quality profile of the essential oils in general. The principal components of chamomile essential oil were significantly affected by the D2P3 treatment. The findings of this study add to our understanding of how to grow high-quality chamomile flowers in arid regions. Full article

(This article belongs to the Special Issue Research Progress and Application Prospect of Medicinal Plants)

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15 pages, 1435 KiB

Open AccessEditor’s ChoiceArticle

Early Season Growth Responses of Resistant and Susceptible Cotton Genotypes to Reniform Nematode and Soil Potassium Application

by Bhupinder Singh, Daryl R. Chastain, Salliana R. Stetina, Emile S. Gardiner and John L. Snider

Agronomy 2022, 12(11), 2895; https://doi.org/10.3390/agronomy12112895 - 19 Nov 2022

Cited by 1 | Viewed by 1840

Abstract

A greenhouse study was conducted to investigate the roles that host plant resistance and soil potassium (K) levels play in affecting Rotylenchulus reniformis Linford and Oliveira (Tylenchida: Hoplolaimidae) (RN) populations and early season cotton (Gossypium hirsutum L.) growth. Two upland, RN-resistant cotton [...] Read more.

A greenhouse study was conducted to investigate the roles that host plant resistance and soil potassium (K) levels play in affecting Rotylenchulus reniformis Linford and Oliveira (Tylenchida: Hoplolaimidae) (RN) populations and early season cotton (Gossypium hirsutum L.) growth. Two upland, RN-resistant cotton lines (G. barbadense introgressions: 08SS110-NE06.OP and 08SS100), a genetic standard (Deltapine 16) and a commercially available susceptible cultivar (PHY 490 W3FE) were evaluated at four different levels of K [100% of recommended rate, 150% of recommended, 50% of recommended, and a base level] from seeding until harvesting, 60 days after sowing (DAS). Quadratic functions (r² = 0.82 to 0.95) best described the early season growth response of cotton genotypes to soil K. The base K level was associated with the lowest values for most morphological variables, including plant height (PH), mainstem nodes (MSN), leaf area, and dry weight at 30 DAS and 60 DAS. However, soil K did not affect RN population counts (RC). Additionally, soil K did not influence the rate of change in growth variables among genotypes. The resistant genotype 08SS110-NE06.OP showed greater growth in terms of time to first true leaf, PH, MSN, and above-ground dry weights compared to the commercially available susceptible genotype. No interaction between K and RN or genotype and RN was found in early season cotton growth. However, RC in pots of resistant genotypes was less than in pots of susceptible genotypes. Our research on the early season growth response to soil K by novel, RN-resistant genotypes and susceptible genotypes contributes to the development of improved RN resistance and fertilization management in cotton. Full article

(This article belongs to the Special Issue Effects of Nematodes on Crops)

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19 pages, 2226 KiB

Open AccessEditor’s ChoiceArticle

Influence of Planting Date on Winter Rye Performance in Kentucky

by Elżbieta Szuleta, Timothy Phillips, Carrie A. Knott, Chad D. Lee and David A. Van Sanford

Agronomy 2022, 12(11), 2887; https://doi.org/10.3390/agronomy12112887 - 18 Nov 2022

Cited by 6 | Viewed by 1523

Abstract

Winter rye (Secale cereale L.) is a grain crop well known for its outstanding tolerance to unfavorable weather and soil conditions. Because of rye’s wide range of possible uses (e.g., cover crop, feed for livestock, bread, cookies, distilled and brewed beverages), its [...] Read more.

Winter rye (Secale cereale L.) is a grain crop well known for its outstanding tolerance to unfavorable weather and soil conditions. Because of rye’s wide range of possible uses (e.g., cover crop, feed for livestock, bread, cookies, distilled and brewed beverages), its pro-health properties and unique flavor, interest in this crop is increasing in the United States. In 2018/2019 and 2019/2020 we tested 24 winter rye varieties that were available in the US at 3 planting dates: early, intermediate, and late. The aims of this study were to (1) identify conventional and hybrid varieties suitable for the US mid-south environment; (2) establish an optimal planting date of winter rye and (3) quantify genotype x planting date interaction. At both locations and in both growing seasons the best yielding, and most resistant to disease and lodging entries were European hybrids (KWS Serafino, KWS Daniello, KWS Bono and KWS Brasetto), and the best yielding conventional varieties were AC Hazlet and ND Dylan. There were statistically significant (p < 0.01 in 2019 and p < 0.0001 in 2020) differences in yield between planting dates both seasons. The response to planting date differed between varieties. In the 2018/2019 growing season we observed that, on average, rye performed better when planted early, but in 2019/2020, a severe May freeze caused extensive damage in early planted rye, and the best planting date was the late one. Overall, the majority of varieties analyzed individually performed the best at intermediate and late planting dates. Full article

(This article belongs to the Section Crop Breeding and Genetics)

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16 pages, 3298 KiB

Open AccessEditor’s ChoiceArticle

Wheat Yield Estimation Using Remote Sensing Indices Derived from Sentinel-2 Time Series and Google Earth Engine in a Highly Fragmented and Heterogeneous Agricultural Region

by Hajar Saad El Imanni, Abderrazak El Harti and Lahcen El Iysaouy

Agronomy 2022, 12(11), 2853; https://doi.org/10.3390/agronomy12112853 - 15 Nov 2022

Cited by 12 | Viewed by 3264

Abstract

In Morocco, monitoring and estimation of wheat yield at the regional and national scales are critical issues for national food security. The recent Sentinel-2 imagery offers potential for managing grain production systems on a field and regional level. The present study was planned [...] Read more.

In Morocco, monitoring and estimation of wheat yield at the regional and national scales are critical issues for national food security. The recent Sentinel-2 imagery offers potential for managing grain production systems on a field and regional level. The present study was planned based on a time series of six remote sensing indices and Multiple Linear Regression (MLR) methods for real-time estimation of wheat yield using the Google Earth Engine (GEE) platform in a highly heterogeneous and fragmented agricultural region, such as the Tadla Irrigated Perimeter (TIP). First, the spatial distribution of wheat in the TIP region was mapped by performing Random Forest (RF) classification of Sentinel 2 images. Following that, using MLR models, the wheat yield of nine sampled fields was estimated for the different phenological stages of wheat. The yield measured in-situ was the independent variable of the regressions. The dependent variables included the remote sensing indices derived from Sentinel-2. The remote sensing index and the phenological period of the greatest model were investigated to estimate and map the wheat yield in the entire study area. The RF generated the wheat mapping of the study area with an overall accuracy (OA) of 93.82%. Furthermore, the coefficient of determination (R²) of the tested MLR was from 0.53 to 0.89, while the Root Mean Square Error (RMSE) varied from 4.29 to 7.78 q ha⁻¹. The best model was the one that uses the Green Normalized Difference Vegetation Index (GNDVI) in the tillering and maturity stages. Full article

(This article belongs to the Special Issue Current Research on Hyperspectral and Multispectral Imaging and Their Applications in Precision Agriculture)

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19 pages, 1323 KiB

Open AccessEditor’s ChoiceArticle

Identification of Genomic Loci Controlling Grain Macro and Micronutrient Variation in a Wild Barley (Hordeum vulgare spp. spontaneum) Diversity Panel

by Jillian A. Abendroth, Ahmad H. Sallam, Brian J. Steffenson, Marcus A. Vinje, Ramamurthy Mahalingam and Jason G. Walling

Agronomy 2022, 12(11), 2839; https://doi.org/10.3390/agronomy12112839 - 14 Nov 2022

Cited by 1 | Viewed by 1836

Abstract

Nutrient deficiencies in humans are problematic on a global scale but are more prevalent in regions where high-quality and nutrient-dense foods are scarce. Developing nutrient-rich crops that thrive in these regions of the world would help alleviate the disparity. We leveraged the wild [...] Read more.

Nutrient deficiencies in humans are problematic on a global scale but are more prevalent in regions where high-quality and nutrient-dense foods are scarce. Developing nutrient-rich crops that thrive in these regions of the world would help alleviate the disparity. We leveraged the wild barley (Hordeum vulgare spp. spontaneum) Diversity Collection (WBDC) (N = 232) to characterize the variation in seed macronutrient (P, K, Ca, and Mg) and micronutrient (B, Cu, Fe, Mn, and Zn) contents found in this subspecies and to reveal chromosomal regions associated with these traits. Most micro- and macronutrients displayed variation in the WBDC and, except for boron and phosphorous, had a modest level of heritability (>0.5). Variation due to environment was significant (p < 0.001) for each element, except iron, and genotype was significant for all the tested nutrients, except boron. Thirty-seven marker–trait associations (MTAs) were detected for three (K, Ca, and Mg) of the four macro- and four (Cu, Fe, Mn, and Zn) of the five micronutrients. Several compelling candidate genes harbored within MTAs were also identified, including ABC transporters, NAC transcription factors, and bZIP transcription factors. Full article

(This article belongs to the Topic Plants Nutrients)

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15 pages, 1963 KiB

Open AccessEditor’s ChoiceArticle

Rice Leaf Chlorophyll Content Estimation Using UAV-Based Spectral Images in Different Regions

by Songtao Ban, Weizhen Liu, Minglu Tian, Qi Wang, Tao Yuan, Qingrui Chang and Linyi Li

Agronomy 2022, 12(11), 2832; https://doi.org/10.3390/agronomy12112832 - 12 Nov 2022

Cited by 13 | Viewed by 2383

Abstract

Estimation of crop biophysical and biochemical characteristics is the key element for crop growth monitoring with remote sensing. With the application of unmanned aerial vehicles (UAV) as a remote sensing platform worldwide, it has become important to develop general estimation models, which can [...] Read more.

Estimation of crop biophysical and biochemical characteristics is the key element for crop growth monitoring with remote sensing. With the application of unmanned aerial vehicles (UAV) as a remote sensing platform worldwide, it has become important to develop general estimation models, which can interpret remote sensing data of crops by different sensors and in different agroclimatic regions into comprehensible agronomy parameters. Leaf chlorophyll content (LCC), which can be measured as a soil plant analysis development (SPAD) value using a SPAD-502 Chlorophyll Meter, is one of the important parameters that are closely related to plant production. This study compared the estimation of rice (Oryza sativa L.) LCC in two different regions (Ningxia and Shanghai) using UAV-based spectral images. For Ningxia, images of rice plots with different nitrogen and biochar application rates were acquired by a 125-band hyperspectral camera from 2016 to 2017, and a total of 180 samples of rice LCC were recorded. For Shanghai, images of rice plots with different nitrogen application rates, straw returning, and crop rotation systems were acquired by a 5-band multispectral camera from 2017 to 2018, and a total of 228 samples of rice LCC were recorded. The spectral features of LCC in each study area were analyzed and the results showed that the rice LCC in both regions had significant correlations with the reflectance at the green, red, and red-edge bands and 8 vegetation indices such as the normalized difference vegetation index (NDVI). The estimation models of LCC were built using the partial least squares regression (PLSR), support vector regression (SVR), and artificial neural network (ANN) methods. The PLSR models tended to be more stable and accurate than the SVR and ANN models when applied in different regions with R² values higher than 0.7 through different validations. The results demonstrated that the rice canopy LCC in different regions, cultivars, and different types of sensor-based data shared similar spectral features and could be estimated by general models. The general models can be implied to a wider geographic extent to accurately quantify rice LCC, which is helpful for growth assessment and production forecasts. Full article

(This article belongs to the Special Issue Intelligent Monitoring, Modeling, Optimization and Control in Smart Agriculture)

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13 pages, 2070 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Diversity and Resistance to Thiophanate-Methyl of Colletotrichum spp. in Strawberry Nursery and the Development of Rapid Detection Using LAMP Method

by Jianyan Wu, Shuodan Hu, Boyang Ye, Xiaoran Hu, Wenfei Xiao, Hong Yu and Chuanqing Zhang

Agronomy 2022, 12(11), 2815; https://doi.org/10.3390/agronomy12112815 - 11 Nov 2022

Cited by 8 | Viewed by 1742

Abstract

Anthracnose is a devastating fungal disease in strawberry nurseries. Multiple Colletotrichum species are responsible for strawberry anthracnose. In this study, 105 Colletotrichum isolates were obtained from strawberry seedlings with anthracnose symptoms in fifteen nurseries located in Zhejiang province, China, and were classified based [...] Read more.

Anthracnose is a devastating fungal disease in strawberry nurseries. Multiple Colletotrichum species are responsible for strawberry anthracnose. In this study, 105 Colletotrichum isolates were obtained from strawberry seedlings with anthracnose symptoms in fifteen nurseries located in Zhejiang province, China, and were classified based on multilocus sequence and morphological characteristic analyses. Analysis of ITS, ACT, CAL, CHS-1, and GAPDH revealed that four species within C. gloeosporioides species complex, including C. siamense (56 isolates, 53.3%), C. fructicola (37 isolates, 35.2%), C. gloeosporioides (7 isolates, 6.7%), and C. aenigma (5 isolates, 4.8%), were detected in diseased seedlings. Thiophanate-methyl is one of the benzimidazole fungicides, and has long been used to control strawberry anthracnose in China. Here, thiophanate-methyl resistance of Colletotrichum isolates was determined by the minimum inhibitory concentration (MIC) method. Our results indicated that the resistance frequency was up to 96.2%, containing 94.3% of highly resistant isolates. Only four sensitive isolates (two C. fructicola, one C. gloeosporioides, and one C. siamense isolates) and two moderately resistant isolates (one C. aenigma isolate and one C. siamense isolate) were detected. Our data indicated that the high resistance was mainly caused by the E198A mutation in the β-tubulin protein. In addition, F200Y (TTC→TAC) in the β-tubulin protein were detected in two moderately resistant isolates. Based on the point mutation at codon 198 (GAG→GCG) in the β-tubulin gene of Colletotrichum isolates, we developed a loop-mediated isothermal amplification (LAMP) assay to rapidly detect the E198A mutants. Collectively, our study indicated that four species within the C. gloeosporioides species complex were associated with anthracnose symptoms in strawberry nurseries in Zhejiang province, and serious resistance was widespread in each Colletotrichum species. Full article

(This article belongs to the Special Issue Plant Anthracnose: Etiology and Current Management Options)

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17 pages, 2549 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Optimal Nutrient Solution and Dose for the Yield of Nuclear Seed Potatoes under Aeroponics

by Jaime B. Silva Filho, Paulo Cezar Rezende Fontes, Jorge F. S. Ferreira, Paulo R. Cecon and Elizabeth Crutchfield

Agronomy 2022, 12(11), 2820; https://doi.org/10.3390/agronomy12112820 - 11 Nov 2022

Cited by 5 | Viewed by 2245

Abstract

The aeroponic production of certified seed potatoes is a booming alternative for arid and semi-arid areas where fresh water is scarce and soil-borne diseases and nematodes preclude field production. Although widely used in aeroponics, nutrient-solution salinity effects have not been evaluated in potatoes. [...] Read more.

The aeroponic production of certified seed potatoes is a booming alternative for arid and semi-arid areas where fresh water is scarce and soil-borne diseases and nematodes preclude field production. Although widely used in aeroponics, nutrient-solution salinity effects have not been evaluated in potatoes. This study aimed to (1) establish the best of two nutrient solutions (Otazú vs. modified Furlani) at 20, 50, 100, and 150% of the crop-recommended dose for seed-potato production, (2) evaluate growth indexes to diagnose plant-N status, and (3) establish a prognosis for the yield of nuclear seed potatoes under aeroponics. At 21 days after transplanting, there was a significant correlation between the nitrate-N petiole-sap test and some of the parameters measured. The 4th leaf indexes correlated with yield parameters indicating that they can be used to prognosticate the final minituber yield. The best parameters to diagnose the N status in potato plants were: 4th leaf area, length, and dry weight (Otazú’s), SPAD, and 4th leaf area (modified Furlani’s). Although both nutrient solutions had similar nitrogen concentrations, Otazú’s nutrient solution at 100% of the recommended nitrogen dose had lower salinity than the modified Furlani’s solution and was the best to produce nuclear seed potatoes. Full article

(This article belongs to the Topic Plants Nutrients)

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21 pages, 1863 KiB

Open AccessEditor’s ChoiceReview

Combined Abiotic Stresses: Challenges and Potential for Crop Improvement

by Rubab Shabbir, Rajesh Kumar Singhal, Udit Nandan Mishra, Jyoti Chauhan, Talha Javed, Sadam Hussain, Sachin Kumar, Hirdayesh Anuragi, Dalpat Lal and Pinghua Chen

Agronomy 2022, 12(11), 2795; https://doi.org/10.3390/agronomy12112795 - 10 Nov 2022

Cited by 27 | Viewed by 4361

Abstract

Abiotic stressors are major constraints that affect agricultural plant physio-morphological and biochemical attributes, resulting in a loss of normal functioning and, eventually, a severe decline in crop productivity. The co-occurrence of different abiotic stresses, rather than a specific stress situation, can alter or [...] Read more.

Abiotic stressors are major constraints that affect agricultural plant physio-morphological and biochemical attributes, resulting in a loss of normal functioning and, eventually, a severe decline in crop productivity. The co-occurrence of different abiotic stresses, rather than a specific stress situation, can alter or trigger a wide range of plant responses, such as altered metabolism, stunted growth, and restricted development. Therefore, systematic and rigorous studies are pivotal for understanding the impact of concurrent abiotic stress conditions on crop productivity. In doing so, this review emphasizes the implications and potential mechanisms for controlling/managing combined abiotic stresses, which can then be utilized to identify genotypes with combined stress tolerance. Furthermore, this review focuses on recent biotechnological approaches in deciphering combined stress tolerance in plants. As a result, agronomists, breeders, molecular biologists, and field pathologists will benefit from this literature in assessing the impact of interactions between combined abiotic stresses on crop performance and development of tolerant/resistant cultivars. Full article

(This article belongs to the Special Issue Climate Changes and Quality of Crops)

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20 pages, 2483 KiB

Open AccessEditor’s ChoiceArticle

Wheat Nutrient Management Strategies to Increase Productivity, Profitability and Quality on Sandy Loam Soils

by Lali Jat, Rama Krishna Naresh, Rajan Bhatt, Mandapelli Sharath Chandra, Sanskriti Singh, S. K. Gupta, Abed Alataway, Ahmed Z. Dewidar and Mohamed A. Mattar

Agronomy 2022, 12(11), 2807; https://doi.org/10.3390/agronomy12112807 - 10 Nov 2022

Cited by 3 | Viewed by 2192

Abstract

By 2050, the population of the world is anticipated to increase from 7.7 billion to 9.7 billion people, and, and wheat is expected to continue to play a vital role in ensuring food security globally. It is the main diet for 40% of [...] Read more.

By 2050, the population of the world is anticipated to increase from 7.7 billion to 9.7 billion people, and, and wheat is expected to continue to play a vital role in ensuring food security globally. It is the main diet for 40% of the world’s population and supplies food for more than 4.5 billion people in 94 countries contains 21% of the joules and 20% of the protein. The present investigations were carried out during rabi 2017–2018 and 2018–2019 to determine how optimal nutrient management (INM) practices enhance fertilizer usage efficiency, productivity, soil health, and viability in wheat (Variety DBW 71) through innovative nutritional sources and their modes of application methods. The treatments comprised of, viz., control, basal applications of recommended NPK (80:60:40)/NPK granules (200 kg/ha) + FYM (5 t ha⁻¹) + bio-stimulant granules (62.5 kg/ha), +NPK bio-fertilizer (seed treatment), along with a top dressing of urea (20 kg/ha)/bio-stimulant (625 mL ha⁻¹)/NPK Powder (1%) sprays (40/55/70 DAS), which had triplicated randomized block design (RBD) at the crop research farm of SVPUA&T, Meerut (U.P.). The results revealed that wheat grown with incorporation of FYM and bio-stimulant –L attained significantly better growth and higher dry matter accumulation across the stages. The crop contained 1.63% N, 0.31% P, 0.69% K in grain, and 0.57% N, 0.11% P and 1.34% K in straw. Such crops exhibited agronomic, physiological, and apparent recovery efficiency of NPK of the order of 3.2 kg kg⁻¹ of nutrient applied, 14.0 kg kg⁻¹ of nutrient uptake, and 0.23% against recommended NPK. Applications of FYM, NPK bio-fertilizer+ urea, and bio-stimulant + NPK sprays worked synergistically and increased grain yields by 29.8, 35.2, 50.3 and 41.1% over their respective controls. The results also indicated that soil organic carbon (0.47%), available NPK (227.0, 27.7, 172.1 kg/ha), dehydrogenase activity, and microbial population (bacteria, fungal and actinomycetes) in soil was also highest with the treatment. Finally, the wheat crop required an investment of Rs ha⁻¹ 131,453 and fetched a net reoccurrence of Rs. 96,154, with benefits of Rs. 3.72 over cost, respectively. Therefore, the study reveals that integrated nutrient management, viz., FYM 5 t ha⁻¹ +NPK (12–32–16) -G @ 200 kg/ha + NPK bio-fertilizer (seed treatment) + urea @ 20 kg/ha, foliar application NPK (18−18−18) -P@ 1% and bio-stimulant –L 0.62 L ha⁻¹ improved the better growth, productivity, soil health and profitability of wheat crops. Finally, to boost production, the region must emphasize the wheat crop’s part in integrated nutrition management with foliar application of bio-stimulants. Furthermore, these investigations must be reinvestigated at different sites with different agro-climatic conditions and texturally divergent soils. Full article

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18 pages, 1968 KiB

Open AccessEditor’s ChoiceArticle

Long-Term Effects of Compost Amendments and Brassica Green Manures in Potato Cropping Systems on Soil and Crop Health and Productivity

by Robert P. Larkin

Agronomy 2022, 12(11), 2804; https://doi.org/10.3390/agronomy12112804 - 10 Nov 2022

Cited by 3 | Viewed by 1972

Abstract

Beneficial soil and crop management practices, such as longer rotations, cover crops and green manures, organic amendments, and reduced tillage, may improve soil and crop health and productivity when incorporated into cropping systems. Long-term trials are needed to assess the full impacts and [...] Read more.

Beneficial soil and crop management practices, such as longer rotations, cover crops and green manures, organic amendments, and reduced tillage, may improve soil and crop health and productivity when incorporated into cropping systems. Long-term trials are needed to assess the full impacts and effects of these systems. In field trials originally established in 2004, three different 3-yr potato cropping systems focused on management goals of soil conservation (SC), soil improvement (SI), and disease suppression (DS) were evaluated and compared to a standard 2-yr rotation (SQ) and a nonrotation control (PP). After 12–15 years and results compiled over a four-year period (2015–2018), the SI system (with history of compost amendments) increased total and marketable tuber yields relative to all other systems, with yields averaging 26 to 36% higher than the standard SQ system and 36 to 59% greater than PP. SI also improved soil properties such as organic matter and soil water content, nutritional characteristics, and microbial activity compared to the other systems. The SI system continued to provide these improvements several years after compost amendments ended, indicating the long-term benefits. The DS system, which included a disease-suppressive green manure rotation crop and fall cover crops, also improved yield (by 16–20%), had higher organic matter content (by 12%), and increased microbial activity (by 22%) relative to SQ, as well as reducing the soilborne tuber diseases black scurf and common scab by 10–30%. The nonrotation PP system resulted in the notable degradation of soil properties and yield over time. These results demonstrate that soil health management practices can be effectively incorporated into viable potato cropping systems to improve soil properties and crop health, and may enhance long-term sustainability. Full article

(This article belongs to the Special Issue Multiple Cropping Systems for Improving Crop Yield and Soil Quality)

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20 pages, 7849 KiB

Open AccessEditor’s ChoiceArticle

Efficient Identification of Apple Leaf Diseases in the Wild Using Convolutional Neural Networks

by Qing Yang, Shukai Duan and Lidan Wang

Agronomy 2022, 12(11), 2784; https://doi.org/10.3390/agronomy12112784 - 09 Nov 2022

Cited by 19 | Viewed by 2474

Abstract

Efficient identification of apple leaf diseases (ALDs) can reduce the use of pesticides and increase the quality of apple fruit, which is of significance to smart agriculture. However, existing research into identifying ALDs lacks models/methods that satisfy efficient identification in the wild environment, [...] Read more.

Efficient identification of apple leaf diseases (ALDs) can reduce the use of pesticides and increase the quality of apple fruit, which is of significance to smart agriculture. However, existing research into identifying ALDs lacks models/methods that satisfy efficient identification in the wild environment, hindering the application of smart agriculture in the apple industry. Therefore, this paper explores an ACCURATE, LIGHTWEIGHT, and ROBUST convolutional neural network (CNN) called EfficientNet-MG, improving the conventional EfficientNet network by the multistage feature fusion (MSFF) method and gaussian error linear unit (GELU) activation function. The shallow and deep convolutional layers usually contain detailed and semantic information, respectively, but conventional EfficientNets do not fully utilize the different stage convolutional layers. Thus, MSFF was adopted to improve the semantic representation capacity of the last layer of features, and GELU was used to adapt to complicated tasks. Further, a comprehensive ALD dataset called AppleLeaf9 was constructed for the wild environment. The experimental results show that EfficientNet-MG achieves a higher accuracy (99.11%) and fewer parameters (8.42 M) than the five classical CNN models, thus proving that EfficientNet-MG achieves more competitive results on ALD identification. Full article

(This article belongs to the Special Issue Computer Vision for Intelligent Crop Identification and Crop Protection)

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17 pages, 37043 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Meeting the Challenges Facing Wheat Production: The Strategic Research Agenda of the Global Wheat Initiative

by Peter Langridge, Michael Alaux, Nuno Felipe Almeida, Karim Ammar, Michael Baum, Faouzi Bekkaoui, Alison R. Bentley, Brian L. Beres, Bettina Berger, Hans-Joachim Braun, Gina Brown-Guedira, Christopher James Burt, Mario Jose Caccamo, Luigi Cattivelli, Gilles Charmet, Peter Civáň, Sylvie Cloutier, Jean-Pierre Cohan, Pierre J. Devaux, Fiona M. Doohan, M. Fernanda Dreccer, Moha Ferrahi, Silvia E. Germán, Stephen B. Goodwin, Simon Griffiths, Carlos Guzmán, Hirokazu Handa, Malcolm John Hawkesford, Zhonghu He, Eric Huttner, Tatsuya M. Ikeda, Benjamin Kilian, Ian Philip King, Julie King, John A. Kirkegaard, Jacob Lage, Jacques Le Gouis, Suchismita Mondal, Ewen Mullins, Frank Ordon, Jose Ivan Ortiz-Monasterio, Hakan Özkan, İrfan Öztürk, Silvia A. Pereyra, Curtis J. Pozniak, Hadi Quesneville, Martín C. Quincke, Greg John Rebetzke, Jochen Christoph Reif, Teresa Saavedra-Bravo, Ulrich Schurr, Shivali Sharma, Sanjay Kumar Singh, Ravi P. Singh, John W. Snape, Wuletaw Tadesse, Hisashi Tsujimoto, Roberto Tuberosa, Tim G. Willis and Xueyong Zhang Show full author list Hide full author list

Agronomy 2022, 12(11), 2767; https://doi.org/10.3390/agronomy12112767 - 07 Nov 2022

Cited by 9 | Viewed by 7453

Abstract

Wheat occupies a special role in global food security since, in addition to providing 20% of our carbohydrates and protein, almost 25% of the global production is traded internationally. The importance of wheat for food security was recognised by the Chief Agricultural Scientists [...] Read more.

Wheat occupies a special role in global food security since, in addition to providing 20% of our carbohydrates and protein, almost 25% of the global production is traded internationally. The importance of wheat for food security was recognised by the Chief Agricultural Scientists of the G20 group of countries when they endorsed the establishment of the Wheat Initiative in 2011. The Wheat Initiative was tasked with supporting the wheat research community by facilitating collaboration, information and resource sharing and helping to build the capacity to address challenges facing production in an increasingly variable environment. Many countries invest in wheat research. Innovations in wheat breeding and agronomy have delivered enormous gains over the past few decades, with the average global yield increasing from just over 1 tonne per hectare in the early 1960s to around 3.5 tonnes in the past decade. These gains are threatened by climate change, the rapidly rising financial and environmental costs of fertilizer, and pesticides, combined with declines in water availability for irrigation in many regions. The international wheat research community has worked to identify major opportunities to help ensure that global wheat production can meet demand. The outcomes of these discussions are presented in this paper. Full article

(This article belongs to the Collection A Series of Special Reviews and Topic Analyses That Explore Major Trends and Challenges in Agronomy)

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17 pages, 1934 KiB

Open AccessEditor’s ChoiceArticle

Long-Term Conservation Tillage and Precision Nutrient Management in Maize–Wheat Cropping System: Effect on Soil Properties, Crop Production, and Economics

by Biswajit Pramanick, Mritunjay Kumar, Banavath Mahesh Naik, Mukesh Kumar, Santosh Kumar Singh, Sagar Maitra, B. S. S. S. Naik, Vishnu D. Rajput and Tatiana Minkina

Agronomy 2022, 12(11), 2766; https://doi.org/10.3390/agronomy12112766 - 06 Nov 2022

Cited by 24 | Viewed by 2569

Abstract

Intensive tillage coupled with imbalanced nutrient management in maize–wheat systems in low-carbon calcareous soils often results in poor productivity vis-à-vis degradation in soil health. Conservation tillage viz. permanent bed planting (PB) and zero tillage (ZT)/direct seeding with residue retention coupled with precision nutrient [...] Read more.

Intensive tillage coupled with imbalanced nutrient management in maize–wheat systems in low-carbon calcareous soils often results in poor productivity vis-à-vis degradation in soil health. Conservation tillage viz. permanent bed planting (PB) and zero tillage (ZT)/direct seeding with residue retention coupled with precision nutrient management might improve soil properties and yield of crops. Concerning this, a long-term experiment was conducted from 2014–2015 to 2020–2021 with a maize–wheat cropping system at TCA, Dholi farm of RPCAU, Pusa. Treatments consisted of three main plots of different tillage practices, viz. PB, ZT, and conventional tillage (CT) and three sub-plots of nutrient management options, viz. farmers’ fertilization practice (FFP), site-specific nutrient management with Nutrient Expert^® (NE) software, and GreenSeeker (GS) based nitrogen-management. From this study, it was observed that both the PB and ZT resulted in about 31–33% and 43–45% improvement in SOC and water-soluble aggregates (WSA), respectively, comparing them under CT. These two conservation tillage practices also improved the other soil bio-chemical properties. Better soil properties under PB and ZT helped in the improvement of system yield by about 13–18% comparing yield under CT. Moreover, both these tillage practices showed an additional net return of USD 330–USD 400 over CT. PB was found a bit better over ZT concerning soil properties, yield, and economics. Comparing nutrient management options, precision nutrition using NE and GS showed significant improvement in the soil bio-chemical parameters, yield, and economics of the cropping system over FFP. SSNM using NE showed slightly better results than GS. Thus, from this long-term study, it can be concluded that the permanent bed system with residue retention and precision nutrition using Nutrient Expert^® software are the best options concerning tillage and nutrient management, respectively, for improvement of the soil properties of problematic calcareous soils, thereby, enhancing the yield and economics of the maize–wheat cropping system. Full article

(This article belongs to the Special Issue Effects of Tillage, Cover Crop and Crop Rotation on Soil)

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12 pages, 635 KiB

Open AccessEditor’s ChoiceArticle

Weed Management by In Situ Cover Crops and Anaerobic Soil Disinfestation in Plasticulture

by Gursewak Singh, Brian Ward, Amnon Levi and Matthew Cutulle

Agronomy 2022, 12(11), 2754; https://doi.org/10.3390/agronomy12112754 - 05 Nov 2022

Viewed by 1578

Abstract

Weeds negatively affect organic vegetable crop growth and profitability. Weed management is the greatest challenge for vegetable organic growers since control options are limited for organic vegetable production. Anaerobic soil disinfestation (ASD) is a novel non-chemical pest management technique that creates anoxic conditions [...] Read more.

Weeds negatively affect organic vegetable crop growth and profitability. Weed management is the greatest challenge for vegetable organic growers since control options are limited for organic vegetable production. Anaerobic soil disinfestation (ASD) is a novel non-chemical pest management technique that creates anoxic conditions in the topsoil layer for a limited time. ASD is primarily based on the addition of labile carbon sources to topsoil to promote anaerobic conditions driven by microorganisms in moist soil mulched with polyethylene film (polyfim). Field studies were conducted in the summer–fall of 2020 and 2021 to determine the efficacy of warm season cover crops used as carbon sources for ASD and their role in weed management. The study used a factorial experimental design with four cover crop residue treatments (sorghum-sudangrass, sunn hemp, both, or none) in two soil aeration conditions (aerated or non-aerated). Cover crops were grown for 75 days, incorporated into the soil, and sealed with totally impermeable film (TIF) clear mulch, followed by a 4-week ASD process. All incorporated cover crop treatments in non-aerated conditions generated moderate to higher anaerobic conditions (0–150 mV) and provided significantly higher (p < 0.05) weed control than all the other treatments tested or controls. Tomato plants transplanted in non-aerated, cover crops incorporated plots were more vigorous and produced higher yields than aerated plots. No phytotoxicity was observed on tomato plants following ASD treatment in any of the treatments tested. This study demonstrated that warm season cover crops could potentially serve as a carbon source for ASD in organic tomato production. Full article

(This article belongs to the Special Issue Sustainable Weed Management: Biological Principles and Improvement of Conventional Methods)

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18 pages, 1748 KiB

Open AccessEditor’s ChoiceArticle

Control of Stored Agro-Commodity Pests Sitophilus granarius and Callosobruchus chinensis by Nitrogen Hypoxic Atmospheres: Laboratory and Field Validations

by Radek Aulicky, Jawad Ali Shah, Vlastimil Kolar, Zhihong Li and Vaclav Stejskal

Agronomy 2022, 12(11), 2748; https://doi.org/10.3390/agronomy12112748 - 05 Nov 2022

Cited by 6 | Viewed by 1683

Abstract

Given the complexity of the practical usage of controlled atmospheres for the protection of agro-commodities, several researchers have pointed out that there is not enough robust scientific documentation regarding the usage of inert gases for their widespread practical application. Therefore, this work evaluated [...] Read more.

Given the complexity of the practical usage of controlled atmospheres for the protection of agro-commodities, several researchers have pointed out that there is not enough robust scientific documentation regarding the usage of inert gases for their widespread practical application. Therefore, this work evaluated various regimes of hypoxic and anoxic nitrogen atmospheres for the control of two key stored-product pests, in laboratory and under field conditions in silos. Sitophilus granarius and Callosobruchus chinensis were selected as the tested species since they are important pests of grain/rice or legumes in Europe and Asia. Under laboratory conditions, we tested nitrogen (N₂) concentrations (from 95 to 100%) and exposure times (1–20 days) on the developmental stages of both pest species. In most developmental stages of S. granarius and C. chinensis, the shortest effective exposure was found for nitrogen concentration of 99%. Based on our laboratory tests, validation studies were subsequently carried out in semi-hermetic steel silos (25t) using continuous nitrogen saturation by on-site built swing pressure generators. It was found that a full control of all stages of S. granarius and C. chinensis was achieved in 11 days of nitrogen exposure, using concentrations ranging above 99% and below 100%. Our work shows that hypoxic nitrogen treatment can be effectively achieved in small steel silos under proper technological and environmental conditions. Full article

(This article belongs to the Special Issue Post-harvest Pest and Disease Management)

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13 pages, 1528 KiB

Open AccessEditor’s ChoiceArticle

Impact of 2,4-D and Glyphosate on Soil Enzyme Activities in a Resistant Maize Cropping System

by Heather L. Tyler

Agronomy 2022, 12(11), 2747; https://doi.org/10.3390/agronomy12112747 - 05 Nov 2022

Cited by 7 | Viewed by 1952

Abstract

Crop varieties resistant to multiple herbicides have been developed to provide better control of weed populations in row-crop fields where glyphosate resistance has become common. These new varieties include lines of maize (Zea mays) resistant to both glyphosate and 2,4-dichlorophenoxyacetic acid [...] Read more.

Crop varieties resistant to multiple herbicides have been developed to provide better control of weed populations in row-crop fields where glyphosate resistance has become common. These new varieties include lines of maize (Zea mays) resistant to both glyphosate and 2,4-dichlorophenoxyacetic acid (2,4-D). As these herbicides have the potential to impact microbial communities in soil, there is concern that their co-application may have a greater effect on activities linked to soil nutrient cycling than if they were applied individually. To investigate this possibility, a field study was conducted on 2,4-D+glyphosate-resistant maize to determine the impact of 2,4-D alone and 2,4-D+glyphosate on extracellular enzyme activity in both bulk and rhizosphere soil. Maize was treated at the V2 and V8 developmental stages. Changes in soil activities were small in magnitude and inconsistent between timepoints. 2,4-D+glyphosate-treated plots had higher beta-glucosidase, cellobiohydrolase, and phosphatase activities, but only after the V2 application in bulk soil in the first year of the study, while no significant effects were observed in the rhizosphere. Enzyme activities were more impacted by soil organic matter than herbicide treatments. These results suggest that, when applied at label rates, 2,4-D+glyphosate application will not adversely affect soil microbial enzyme activities. Full article

(This article belongs to the Special Issue Impact of Agrochemicals on Soil)

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16 pages, 6787 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

An AI Based Approach for Medicinal Plant Identification Using Deep CNN Based on Global Average Pooling

by Rahim Azadnia, Mohammed Maitham Al-Amidi, Hamed Mohammadi, Mehmet Akif Cifci, Avat Daryab and Eugenio Cavallo

Agronomy 2022, 12(11), 2723; https://doi.org/10.3390/agronomy12112723 - 02 Nov 2022

Cited by 19 | Viewed by 13929

Abstract

Medicinal plants have always been studied and considered due to their high importance for preserving human health. However, identifying medicinal plants is very time-consuming, tedious and requires an experienced specialist. Hence, a vision-based system can support researchers and ordinary people in recognising herb [...] Read more.

Medicinal plants have always been studied and considered due to their high importance for preserving human health. However, identifying medicinal plants is very time-consuming, tedious and requires an experienced specialist. Hence, a vision-based system can support researchers and ordinary people in recognising herb plants quickly and accurately. Thus, this study proposes an intelligent vision-based system to identify herb plants by developing an automatic Convolutional Neural Network (CNN). The proposed Deep Learning (DL) model consists of a CNN block for feature extraction and a classifier block for classifying the extracted features. The classifier block includes a Global Average Pooling (GAP) layer, a dense layer, a dropout layer, and a softmax layer. The solution has been tested on 3 levels of definitions (64 × 64, 128 × 128 and 256 × 256 pixel) of images for leaf recognition of five different medicinal plants. As a result, the vision-based system achieved more than 99.3% accuracy for all the image definitions. Hence, the proposed method effectively identifies medicinal plants in real-time and is capable of replacing traditional methods. Full article

(This article belongs to the Special Issue Imaging Technology for Detecting Crops and Agricultural Products)

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16 pages, 1208 KiB

Open AccessEditor’s ChoiceReview

Biological Control of Fall Armyworm, Spodoptera frugiperda

by Arzlan Abbas, Farman Ullah, Muhammad Hafeez, Xiao Han, Muhammad Zulqar Nain Dara, Hina Gul and Chen Ri Zhao

Agronomy 2022, 12(11), 2704; https://doi.org/10.3390/agronomy12112704 - 31 Oct 2022

Cited by 22 | Viewed by 10197

Abstract

The fall armyworm (FAW), Spodoptera frugiperda, is one of the most important invasive pests worldwide, resulting in considerable losses in host crops. FAW comprises two genetic strains, such as the “rice strain”, which prefers rice and other grass species, and the “maize [...] Read more.

The fall armyworm (FAW), Spodoptera frugiperda, is one of the most important invasive pests worldwide, resulting in considerable losses in host crops. FAW comprises two genetic strains, such as the “rice strain”, which prefers rice and other grass species, and the “maize strain”, which feeds upon maize and sorghum. Potential control measures are generally more applicable to the farmers who lack financial assets to buy chemical insecticides or costly pure seeds. The adverse effects of pesticides on the ecosystem and human’s health and the development of resistance to insect pests have exaggerated efforts to find an alternative strategy that is cost-effective, low-risk and target-specific. Therefore, biological control is widely considered as one of the most important options for insect pest management. This comprehensive review amasses the information on biological control in all phases of their development, including predators, parasitoids, entomopathogenic fungi, viruses, nematodes, bacteria, and biopesticides, with a special focus on their effectiveness against FAW. The findings regarding biological control are briefly discussed in light of improving management programs of the invasive pest S. frugiperda. Full article

(This article belongs to the Special Issue Ecological Management of Pests)

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13 pages, 4399 KiB

Open AccessEditor’s ChoiceArticle

Evaluation of Diode Laser Treatments to Manage Weeds in Row Crops

by Canicius Mwitta, Glen C. Rains and Eric Prostko

Agronomy 2022, 12(11), 2681; https://doi.org/10.3390/agronomy12112681 - 28 Oct 2022

Cited by 1 | Viewed by 2694

Abstract

Herbicides have been the primary weed management practice in agriculture for decades. However, due to their effects on the environment in addition to weeds becoming resistant, alternative approaches to weed control are critical. One approach is using lasers, particularly diode lasers because of [...] Read more.

Herbicides have been the primary weed management practice in agriculture for decades. However, due to their effects on the environment in addition to weeds becoming resistant, alternative approaches to weed control are critical. One approach is using lasers, particularly diode lasers because of their portability, low power demand, and cost effectiveness. In this research, weeds’ response to diode laser treatments was investigated. Three experiments were conducted. The first experiment involved treating two species of weeds with four different laser powers to determine the time it takes to sever the weed stem. The second experiment involved monitoring the status of two species of weeds for a week after treating them with two lasers at constant application times of 1 s, 2 s, and 3 s. The third experiment was a repeat of the second with higher laser powers and shorter treatment times. The results showed diode lasers have a potential to be an effective weed controlling tool. Weed stem diameter, laser power, treatment duration, and distance between laser and weed were all statistically significant in weed mortality, with weed species having no significance. Furthermore, it was found that weed management is possible by exposing the stem of the two weed species between 0.8 and 2.65 mm diameter to a laser beam dosage without necessarily severing it, with 80% effectiveness at 0.5 s treatment time, and 100% effectiveness using a 6.1 W laser for 1.5 s. Full article

(This article belongs to the Special Issue The Future of Weed Science—Novel Approaches to Weed Management)

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18 pages, 3291 KiB

Open AccessEditor’s ChoiceArticle

The Effects of Winter Cover Crops on Maize Yield and Crop Performance in Semiarid Conditions—Artificial Neural Network Approach

by Bojan Vojnov, Goran Jaćimović, Srđan Šeremešić, Lato Pezo, Biljana Lončar, Đorđe Krstić, Svetlana Vujić and Branko Ćupina

Agronomy 2022, 12(11), 2670; https://doi.org/10.3390/agronomy12112670 - 28 Oct 2022

Cited by 15 | Viewed by 2040

Abstract

Maize is the most widespread and, along with wheat, the most important staple crop in the Republic of Serbia, which is of great significance for ensuring national food security. With the increasing demand for food and forage, intensive agricultural practices have been adopted [...] Read more.

Maize is the most widespread and, along with wheat, the most important staple crop in the Republic of Serbia, which is of great significance for ensuring national food security. With the increasing demand for food and forage, intensive agricultural practices have been adopted in the maize production systems. In this direction, considerable research efforts have been made to examine the effects of different types of cover crops as a green manure on maize productivity; however, no consistent conclusions have been reached so far. Therefore, the objective of the present study is to examine the possibility of predicting the effects of winter cover crops (CC) integrated with different management practices on the morphological traits, yield, and yield components of maize. The experiment was carried out on chernozem soil from 2016 to 2020 as a randomized complete block design arranged as a split-split-plot with three replicates. The pea as a sole crop (P) and the mixture of pea and triticale (PT) are sown as winter CC with the following subplots: (i) CC used as green manure, and (ii) CC used as forage and removed before maize sowing. The artificial neural network is used for exploring nonlinear functions of the tested parameters and 13 categorical input variables for modeling according to the following factors: CC, way of using CC, N fertilization, and year. The computed maximums of plant height, number of leaves, number of internodes, plant density, number of ears, grain yield, 1000-grain weight, hectolitre weight, dry matter harvest residue, harvest index, leaves percentage, stems percentage, and ears percentage are as follows: 232.3 cm; 9.7; 10.2; 54,340 plants ha⁻¹; 0.9; 9.8 t ha⁻¹; 272.4 g; 67.0 kg HL⁻¹; 9.2 t ha⁻¹; 0.52; 18.9%; 36.0%, and 45.1%, respectively. The optimal result is obtained with peas used as green manure, with 50 kg N ha⁻¹ and in the climatic conditions of 2018. Consequently, maize production under subsequent sowing periods can be successfully optimized by adapting selected management options for higher yield accomplishment. Full article

(This article belongs to the Special Issue Conservation Agriculture as a Key Challenge for Sustainable Agroecosystems in Climate Change Mitigation and Adaptation - Series II)

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18 pages, 1709 KiB

Open AccessEditor’s ChoiceArticle

The Impact of Polymer on the Productivity and Photosynthesis of Soybean under Different Water Levels

by Lucas Felisberto Pereira, Walter Quadros Ribeiro Júnior, Maria Lucrecia Gerosa Ramos, Guilherme Filgueiras Soares, Cristiane Andréa de Lima Guimarães, Sebastião Pedro da Silva Neto, Onno Muller, Christina Cleo Vinson, André Ferreira Pereira and Thomas Christopher Rhys Williams

Agronomy 2022, 12(11), 2657; https://doi.org/10.3390/agronomy12112657 - 27 Oct 2022

Viewed by 1169

Abstract

In order to practice sustainable and resource-efficient agriculture, the use of new technologies such as water-retaining polymers is essential. The objective of this study was to evaluate the effect of a polymer incorporated into the soil on gas exchange and yield under different [...] Read more.

In order to practice sustainable and resource-efficient agriculture, the use of new technologies such as water-retaining polymers is essential. The objective of this study was to evaluate the effect of a polymer incorporated into the soil on gas exchange and yield under different water regimes (WR) in three soybean cultivars. The experiment was conducted at Embrapa Cerrados under field conditions in 2016 and 2017, using three different cultivars (BRS 5980IPRO, NA 5909RG and BRS 7280RR). Soybean cultivars were submitted to four water regimes (representing 30%, 50%, 83% and 100% of evapotranspiration replacement, namely WR1, WR2, WR3 and WR4). No beneficial results were observed in 2016 with Polymer. Most of the reductions in photosynthesis and transpiration by adding the polymer can be attributed to stomatal control, but such reductions did not influence productivity. In 2017, the yield was higher using Polymer in WR4 and WR3 by 40 to 20%, depending on the cultivar. Under severe stress (WR2 and WR1), reduced gas exchange was obtained with Polymer, but the yield was not reduced. These results indicate that Polymer contributed to the prolongation of photosynthetic activity during the reproductive phase of soybean and may represent a potential strategy for increasing yield under moderate drought stress. Full article

(This article belongs to the Special Issue Management Alternatives in Legumes Cropping)

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16 pages, 2520 KiB

Open AccessEditor’s ChoiceArticle

Characterization of the Volatile Profiles of Six Industrial Hemp (Cannabis sativa L.) Cultivars

by Fern Kumeroa, Shanika Komahan, Svetla Sofkova-Bobcheva and Andrea Clavijo McCormick

Agronomy 2022, 12(11), 2651; https://doi.org/10.3390/agronomy12112651 - 27 Oct 2022

Cited by 5 | Viewed by 3886

Abstract

Volatile organic compounds (VOCs) play an important role in plant ecology and can be useful in pest management. This work characterises, for the first time, the VOC emissions of six industrial hemp (Cannabis sativa L.) cultivars grown in New Zealand: CFX-2, CRS-1, [...] Read more.

Volatile organic compounds (VOCs) play an important role in plant ecology and can be useful in pest management. This work characterises, for the first time, the VOC emissions of six industrial hemp (Cannabis sativa L.) cultivars grown in New Zealand: CFX-2, CRS-1, Ferimon 12, Katani, Futura 75, and Finola. Volatiles emitted from flowers and foliage of eight-week-old plants were collected using a dynamic headspace sampling method and analysed using gas chromatography coupled to mass spectrometry. We assessed the effect of cultivar, sex (monoecious, male, and female), and site (i.e., two sites differing in soil types, maintained under irrigation and rain-fed conditions) on VOC emissions. Thirty-five volatile compounds were tentatively identified from the headspace samples of hemp plants, but none of the cultivars emitted all 35 compounds. β-Myrcene was the most abundant compound in most cultivars. Overall, there was a significant effect of sex, and the interaction of sex and cultivar on the volatile profiles, but no effect of site. Female plants typically emitted more volatiles than their male counterparts and monoecious cultivars. The main compounds driving the difference between cultivars and sexes were (Z)- and (E)-β-ocimene. We hypothesize that differences in emission emerged as a defence strategy to protect costly female flowers from herbivores (since C. sativa is wind pollinated), but this hypothesis needs further testing. We recommend additional studies exploring how biotic and abiotic factors influence hemp VOC emissions, changes in VOCs throughout the crop cycle, the role of VOCs in plant-insect interactions and their use in pest management. Full article

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25 pages, 2589 KiB

Open AccessEditor’s ChoiceReview

Convolutional Neural Networks in Computer Vision for Grain Crop Phenotyping: A Review

by Ya-Hong Wang and Wen-Hao Su

Agronomy 2022, 12(11), 2659; https://doi.org/10.3390/agronomy12112659 - 27 Oct 2022

Cited by 32 | Viewed by 4802

Abstract

Computer vision (CV) combined with a deep convolutional neural network (CNN) has emerged as a reliable analytical method to effectively characterize and quantify high-throughput phenotyping of different grain crops, including rice, wheat, corn, and soybean. In addition to the ability to rapidly obtain [...] Read more.

Computer vision (CV) combined with a deep convolutional neural network (CNN) has emerged as a reliable analytical method to effectively characterize and quantify high-throughput phenotyping of different grain crops, including rice, wheat, corn, and soybean. In addition to the ability to rapidly obtain information on plant organs and abiotic stresses, and the ability to segment crops from weeds, such techniques have been used to detect pests and plant diseases and to identify grain varieties. The development of corresponding imaging systems to assess the phenotypic parameters, yield, and quality of crop plants will increase the confidence of stakeholders in grain crop cultivation, thereby bringing technical and economic benefits to advanced agriculture. Therefore, this paper provides a comprehensive review of CNNs in computer vision for grain crop phenotyping. It is meaningful to provide a review as a roadmap for future research in such a thriving research area. The CNN models (e.g., VGG, YOLO, and Faster R-CNN) used CV tasks including image classification, object detection, semantic segmentation, and instance segmentation, and the main results of recent studies on crop phenotype detection are discussed and summarized. Additionally, the challenges and future trends of the phenotyping techniques in grain crops are presented. Full article

(This article belongs to the Special Issue Computer Vision for Intelligent Crop Identification and Crop Protection)

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