Agronomy

11 pages, 1312 KiB

Open AccessArticle

Soil Penetration Resistance Influenced by Eucalypt Straw Management under Mechanized Harvesting

by Judyson de M. Oliveira, Cássio A. Tormena, Gérson R. dos Santos, Lincoln Zotarelli, Raphael B. A. Fernandes and Teógenes S. de Oliveira

Agronomy 2022, 12(6), 1482; https://doi.org/10.3390/agronomy12061482 - 20 Jun 2022

Viewed by 1637

Abstract

This study aimed to evaluate the impacts of mechanized harvesting and soil tillage on soil penetration resistance (PR), influenced by the eucalypt straw management under sandy clay Oxisol in Southern Brazil. The study was conducted in a eucalyptus production area under Oxisol in [...] Read more.

This study aimed to evaluate the impacts of mechanized harvesting and soil tillage on soil penetration resistance (PR), influenced by the eucalypt straw management under sandy clay Oxisol in Southern Brazil. The study was conducted in a eucalyptus production area under Oxisol in Paraná State, Brazil. The treatments consisted of two harvesting systems: harvester + forwarder (HF) and feller + skidder (FS) both applied in areas under coppicing and stand renewal eucalypt cultivation systems. For stand renewal areas, eucalypt straw was managed on the soil surface at levels of 100, 50, and 0% before soil tillage. PR and soil moisture measurements were made in points distributed in regular grid for all treatments. This grid also was used to evaluate the geospatial behavior of PR in the stand renewal areas. During the measuring of PR, the averages (± confidence interval) of soil moisture up to 0–0.60 m depth were 0.20 ± 0.01 and 0.24 ± 0.01 in coppicing and stand renewal areas, respectively. In areas under coppicing, the PR mean ± confidence interval at 0–0.05 m layer in HF (1.28 ± 0.24 MPa) was lower than in FS treatment (2.11 ± 0.44 MPa). However, the PR values were similar between treatments in stand renewal areas, regardless of the forest straw level on the soil surface. For both harvesting systems, there was a lack of spatial dependence of PR up to 0.40 m soil depth, indicating some physical and mechanical homogenization induced by the soil tillage in the layer. Eucalypt straw contributed to mitigating effects of harvest traffic on PR level in coppicing forest systems. However, different levels of eucalypt straw managed before soil tillage did not influence PR levels in stand renewal forest systems. Full article

(This article belongs to the Special Issue Tillage, Soil Management, and Field Traffic: Impact on Soil Physical and Mechanical Properties)

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14 pages, 1043 KiB

Open AccessArticle

Carbon Budget of Paddy Fields after Implementing Water-Saving Irrigation in Northeast China

by Tiecheng Li, Tangzhe Nie, Peng Chen, Zuohe Zhang, Jiaxin Lan, Zhongxue Zhang, Zhijuan Qi, Yu Han and Lili Jiang

Agronomy 2022, 12(6), 1481; https://doi.org/10.3390/agronomy12061481 - 20 Jun 2022

Cited by 2 | Viewed by 1780

Abstract

Water-saving irrigation is recognized as an effective agricultural management due to water security and environmental protection problems. In Northeast China, an increasing number of paddy fields are shifting from conventional irrigation to water-saving irrigation. However, there is limited knowledge regarding the carbon (C) [...] Read more.

Water-saving irrigation is recognized as an effective agricultural management due to water security and environmental protection problems. In Northeast China, an increasing number of paddy fields are shifting from conventional irrigation to water-saving irrigation. However, there is limited knowledge regarding the carbon (C) budget of paddy fields after implementing water-saving irrigation in Northeast China. A 2-year consecutive field study was performed from 2018 to 2019 using three different irrigation regimes (conventional irrigation (FI), controlled irrigation (CI), and intermittent irrigation (II)) and two nitrogen (N) fertilization levels (110 and 165 kg N ha⁻¹) in a paddy field of Northeast China. The present study aimed to quantify the net ecosystem C budget (NECB) and net global warming potential (net GWP) after the implementation of water-saving irrigation in Northeast China. Both CI and II enhanced the C sequestration capacity of this paddy field. The net primary productivity (NPP) under CI and II was higher than FI by 18–38% and 11–33%, respectively, when the same N fertilization level was applied. The NECB ranged from 1151 to 2663 kg C ha⁻¹, indicating that all treatments acted as net C sinks. II increased the NECB through increasing NPP, which exceeded increased removal of harvest and C mineralized losses. Under II, the NECB was significantly higher than FI and CI when the same N fertilization level was applied (p < 0.05). The net GWP under II and CI was significantly lower than FI (p < 0.05). The net GWP under II was lower than CI when the N fertilization level was 165 kg N ha⁻¹, but no significant differences were detected. These results demonstrated that the II with 165 kg N ha⁻¹ of paddy fields strongly decreased net GWP in Northeast China to combat global climate change. Full article

(This article belongs to the Special Issue Low Carbon Agriculture and Low Reactive Nitrogen Losses under Intensification)

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14 pages, 1197 KiB

Open AccessArticle

Microdosing of Compost for Sustainable Production of Improved Sorghum in Southern Mali

by Moumini Guindo, Bouba Traoré, Birhanu Zemadim Birhanu, Alou Coulibaly and Ramadjita Tabo

Agronomy 2022, 12(6), 1480; https://doi.org/10.3390/agronomy12061480 - 20 Jun 2022

Cited by 6 | Viewed by 2003

Abstract

The depletion of soil organic matter is one of the major challenges constraining agricultural production in the southern zone of Mali. This study evaluated the effects of compost types, methods, and dose applications on the productivity and sustainability of sorghum. Two types of [...] Read more.

The depletion of soil organic matter is one of the major challenges constraining agricultural production in the southern zone of Mali. This study evaluated the effects of compost types, methods, and dose applications on the productivity and sustainability of sorghum. Two types of compost (farmer practice and cotton stems) were applied to sorghum at two rates (microdosing at 2.5 t ha⁻¹ and broadcasting at 5 t ha⁻¹) and evaluated on 30 farmer fields in 2019 and 2020. The treatments used included CPA (cotton stem compost at 5 t ha⁻¹ + 100 kg ha⁻¹ DAP), CPA (cotton stem compost at 2.5 t ha⁻¹ + 100 kg ha⁻¹ DAP), CP (farmer compost at 5 t ha⁻¹ + 100 kg ha⁻¹ DAP), CP (famer compost at 2.5 t ha⁻¹ + 100 kg ha⁻¹ DAP), control (100 kg ha⁻¹ DAP), and control. The results showed that regardless of the compost type, applying a microdose of 2.5 t ha⁻¹ improved the growth rate, plant height, grain yield, and biomass yield by 15%, 18%, 47%, and 27%, respectively, when compared to the control. No statistical difference was observed in the yield of 2061 kg ha⁻¹ between applying compost by microdosing at 2.5 t ha⁻¹ and broadcasting at 5 t ha⁻¹. It can be inferred that the application of compost by microdosing makes it possible to achieve a 100% fertilized surface compared to broadcasting, with a nitrogen use efficiency of more than 55%. The application of compost by microdosing at 2.5 t ha⁻¹ resulted in an economic gain of 334,800 XOF ha⁻¹, which was 27% higher than that obtained with the application of compost by broadcasting at 5 t ha⁻¹. Conversely, the contribution to the improvement of soil nitrogen stock varied from 12–20% with a microdose of 2.5 t ha⁻¹ compared to 100% for broadcasting compost at 5 t ha⁻¹ per application. Therefore, the availability of cotton stems in the southern zone of Mali presents an opportunity for farmers to implement compost microdose technology to double the fertilized area and improve sorghum productivity. Full article

(This article belongs to the Special Issue Cropping Systems and Agronomic Management Practices of Field Crops)

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15 pages, 3698 KiB

Open AccessArticle

Boron Effects on Fruit Set, Yield, Quality and Paternity of Hass Avocado

by Nimanie S. Hapuarachchi, Wiebke Kämper, Helen M. Wallace, Shahla Hosseini Bai, Steven M. Ogbourne, Joel Nichols and Stephen J. Trueman

Agronomy 2022, 12(6), 1479; https://doi.org/10.3390/agronomy12061479 - 20 Jun 2022

Cited by 5 | Viewed by 3265

Abstract

Boron plays a critical role in pollination and fertilization and can affect fruit set and yield. We applied 0 g, 15 g (manufacturer recommendation) or 30 g boron pre-flowering to Hass avocado trees to determine the effects on fruit set, fruitlet paternity, yield, [...] Read more.

Boron plays a critical role in pollination and fertilization and can affect fruit set and yield. We applied 0 g, 15 g (manufacturer recommendation) or 30 g boron pre-flowering to Hass avocado trees to determine the effects on fruit set, fruitlet paternity, yield, fruit size, mineral nutrient concentrations and fatty acid composition. The boron applications did not significantly affect the initial fruit set at 3 or 6 weeks after peak anthesis or the proportions of self-pollinated fruitlets or mature fruit. Approximately 88–92% of the mature fruit were self-pollinated. However, applying 30 g boron per tree reduced the fruit set at 10 weeks after peak anthesis by 56% and the final yield by 25%. Attaining > 90% of the maximum yield was associated with foliar boron concentrations being below 104 mg/kg at 6 weeks after peak anthesis and between 39 and 68 mg/kg at 28 weeks after peak anthesis. Applying 15 g boron per tree increased the fruit mass by 5%, fruit diameter by 2%, flesh mass by 9%, flesh boron concentration by 55%, and the relative abundance of unsaturated fatty acids by 1% compared with control trees. Applying the recommended amount of boron provided a good yield of high-quality avocado fruit but applying boron at double the recommended rate reduced the yield. Full article

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14 pages, 2293 KiB

Open AccessArticle

Assessment of the Physiological Response and Productive Performance of Vegetable vs. Conventional Soybean Cultivars for Edamame Production

by Laura Matos Ribera, Eduardo Santana Aires, Caio Scardini Neves, Gustavo do Carmo Fernandes, Filipe Pereira Giardini Bonfim, Roanita Iara Rockenbach, João Domingos Rodrigues and Elizabeth Orika Ono

Agronomy 2022, 12(6), 1478; https://doi.org/10.3390/agronomy12061478 - 20 Jun 2022

Cited by 1 | Viewed by 1802

Abstract

Because there is a close relationship between plant physiological response and crop performance, the current study aims to evaluate the photosynthetic efficiency and productive performance of vegetable versus conventional soybean cultivars for edamame production. The study was conducted at the School of Agriculture [...] Read more.

Because there is a close relationship between plant physiological response and crop performance, the current study aims to evaluate the photosynthetic efficiency and productive performance of vegetable versus conventional soybean cultivars for edamame production. The study was conducted at the School of Agriculture (FCA UNESP), Botucatu-SP, Brazil. The treatments in this study included soybean cultivars: vegetable-type BRS 267, vegetable-type BRSMG 790A), and type soybean cultivar grain 58HO124 EP RR, with ten repetitions per treatment in a completely randomized block design. Gas exchange and the response of the cultivars to light were evaluated for photosynthetic characterization. The first pod insertion height, plant height, number of pods per plant, and production in immature grains were all assessed for cultivar productive performance. The type of soybean cultivar grain and vegetable types of soybean showed different behaviors on physiology and yield. The vegetable-types BRS 267 and BRSMG 790A had the highest average for first pod insertion height. The vegetable type BRS 267, whose photoassimilates were designated for vegetative development, had the greatest average plant height. The conventional type 58HO124 EP RR showed greater assimilation of CO₂; however, the photoassimilates were directed to floral emission because such features are inherent in its ability. Finally, vegetable-type BRSMG 790A produced the most immature grains per plant while also having the greatest first pod insertion height, being the best in converting photoassimilates for edamame production. Full article

(This article belongs to the Special Issue Researches on Crop Nutritional Molecular Biology)

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16 pages, 8418 KiB

Open AccessArticle

Xiaomila Green Pepper Target Detection Method under Complex Environment Based on Improved YOLOv5s

by Fenghua Wang, Zhexing Sun, Yu Chen, Hao Zheng and Jin Jiang

Agronomy 2022, 12(6), 1477; https://doi.org/10.3390/agronomy12061477 - 20 Jun 2022

Cited by 11 | Viewed by 2289

Abstract

Real-time detection of fruit targets is a key technology of the Xiaomila green pepper (Capsicum frutescens L.) picking robot. The complex conditions of orchards make it difficult to achieve accurate detection. However, most of the existing deep learning network detection algorithms cannot [...] Read more.

Real-time detection of fruit targets is a key technology of the Xiaomila green pepper (Capsicum frutescens L.) picking robot. The complex conditions of orchards make it difficult to achieve accurate detection. However, most of the existing deep learning network detection algorithms cannot effectively detect Xiaomila green pepper fruits covered by leaves, branches, and other fruits in natural scenes. As detailed in this paper, the Red, Green, Blue (RGB) images of Xiaomila green pepper in the green and mature stage were collected under natural light conditions for building the dataset and an improved YOLOv5s model (YOLOv5s-CFL) is proposed to improve the efficiency and adaptability of picking robots in the natural environment. First, the convolutional layer in the Cross Stage Partial (CSP) is replaced with GhostConv, the detection speed is improved through a lightweight structure, and the detection accuracy is enhanced by adding a Coordinate Attention (CA) layer and replacing Path Aggregation Network (PANet) in the neck with Bidirectional Feature Pyramid Network (BiFPN). In the experiment, the YOLOv5s-CFL model was used to detect the Xiaomila, and the detection results were analyzed and compared with those of the original YOLOv5s, YOLOv4-tiny, and YOLOv3-tiny models. With these improvements, the Mean Average Precision (mAP) of YOLOv5s-CFL is 1.1%, 6.8%, and 8.9% higher than original YOLOv5s, YOLOv4-tiny, and YOLOv3-tiny, respectively. Compared with the original YOLOv5 model, the model size is reduced from 14.4 MB to 13.8 MB, and the running speed is reduced from 15.8 to 13.9 Gflops. The experimental results indicate that the lightweight model improves the detection accuracy and has good real-time performance and application prospects in the field of picking robots. Full article

(This article belongs to the Special Issue Application of Deep Learning in Precise Analysis of Agricultural Crops)

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15 pages, 1173 KiB

Open AccessArticle

Comparative Response of Mango Fruit towards Pre- and Post-Storage Quarantine Heat Treatments

by Saqib Javed, Huimin Fu, Amjad Ali, Atif Nadeem, Muhammad Amin, Kashif Razzaq, Sami Ullah, Ishtiaq A. Rajwana, Shafa Nayab, Vasileios Ziogas, Ping Liu and Syed Bilal Hussain

Agronomy 2022, 12(6), 1476; https://doi.org/10.3390/agronomy12061476 - 20 Jun 2022

Cited by 3 | Viewed by 2749

Abstract

The present study investigates the comparative effect of pre- and post-storage quarantine heat treatments (hot water treatment (HWT) and vapor heat treatment (VHT)) on the post-harvest performance of the mango fruit cv. ‘Chenab Gold’. The results indicate that the application of HWT at [...] Read more.

The present study investigates the comparative effect of pre- and post-storage quarantine heat treatments (hot water treatment (HWT) and vapor heat treatment (VHT)) on the post-harvest performance of the mango fruit cv. ‘Chenab Gold’. The results indicate that the application of HWT at 48 °C for 60 min or VHT at 47 °C for 25 min after 21 days under cold storage enhanced the ethylene production and fruit weight loss, while decreasing fruit firmness and vitamin C content. Noticeably, the post-storage heat treatments ruptured the fruit and destroyed their market value. However, fruit treated with HWT or VHT at harvest exhibited slow weight loss, better skin color, and maintained biochemical attributes as compared to the control when kept under ambient storage conditions. Taken together, the application of hot water before storage has a positive influence on mango fruit quality, while post-storage heat treatment has a devastating impact upon fruit quality and shelf life, cancelling its potential commercial application. Full article

(This article belongs to the Special Issue Principles and Practices in Fruit Tree Production and Postharvest Management)

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13 pages, 310 KiB

Open AccessArticle

Sewage Sludge Ash-Based Biofertilizers as a Circular Approach to Phosphorus: The Issue of Fe and Al in Soil and Wheat and Weed Plants

by Magdalena Jastrzębska, Marta K. Kostrzewska and Agnieszka Saeid

Agronomy 2022, 12(6), 1475; https://doi.org/10.3390/agronomy12061475 - 19 Jun 2022

Viewed by 1872

Abstract

Sewage sludge management for fertilizer purposes can be a step in the circular phosphorus (P) economy. Using microbial solubilization in manufacturing fertilizers from recycled materials is an innovative approach with the potential to increase P compounds’ bioavailability, and fertilizers from sewage sludge ash [...] Read more.

Sewage sludge management for fertilizer purposes can be a step in the circular phosphorus (P) economy. Using microbial solubilization in manufacturing fertilizers from recycled materials is an innovative approach with the potential to increase P compounds’ bioavailability, and fertilizers from sewage sludge ash and P-solubilizing bacteria are promising products of this technology. In addition to P and a range of macronutrients, these fertilizers contain small amounts of micronutrients and potentially toxic elements. This paper discusses the effects of fertilizer on iron (Fe) and aluminum (Al) content in soil, test plants (spring or winter wheat; grain and straw), weeds and post-harvest residues, based on field experiments. Treatments with conventional P fertilizers (superphosphate, phosphorite) and without P fertilization provided references. The tested biofertilizers containing the Bacillus megaterium or Acidithiobacillus ferrooxidans strain had no effect on total Fe and Al content in the soil or on the concentration of these elements in plant biomass when applied at P doses up to 35.2 kg ha^–1. Fe and Al levels in grain did not suggest a potential risk to consumers. Full article

(This article belongs to the Special Issue New Advances on Nutrient Recovery from Municipal, Agro-Industrial and Livestock Wastes for Sustainable Farming 2.0)

19 pages, 677 KiB

Open AccessArticle

Optimum Plant Density for Increased Groundnut Pod Yield and Economic Benefits in the Semi-Arid Tropics of West Africa

by Haile Desmae, Dramane Sako and Djeneba Konate

Agronomy 2022, 12(6), 1474; https://doi.org/10.3390/agronomy12061474 - 19 Jun 2022

Viewed by 3026

Abstract

Groundnut is a very important crop in the West and Central Africa (WCA) region, accounting for almost 70% of Africa’s groundnut production in 2019. Despite its economic importance, the crop’s yield is still low. For a high yield and profitable economic returns, optimal [...] Read more.

Groundnut is a very important crop in the West and Central Africa (WCA) region, accounting for almost 70% of Africa’s groundnut production in 2019. Despite its economic importance, the crop’s yield is still low. For a high yield and profitable economic returns, optimal plant density is a fundamental crop management practice. Plant density experiments were conducted at the ICRISAT-Mali research station between 2016 and 2021 over the main rainy and dry seasons to determine the optimum density for maximum groundnut yield and economic benefits. The treatments contained row spacing of 20 cm, 30 cm, 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, and 100 cm, with intra-row spacing of 10 cm, 15 cm, and 20 cm. Results showed that when plant density was increased, dry pod yield, production value, and net economic benefit per hectare increased in a no moisture stress scenario. During the rainy season, the 40 cm × 10 cm spacing gave the highest dry pod yield (1693 kg), production value ($891.6), and net benefit ($403.5) per hectare. The highest dry pod yield (3703 kg), production value ($2173), and net benefit ($1510.2) per hectare were obtained from 30 cm × 10 cm spacing during the dry season. The number of pods per plant and 100 SW increased with lower plant densities. Therefore, it is recommended to increase plant density to at least 222,000 plants per hectare in the Sudan Savannah agroecology of WCA. Full article

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16 pages, 4457 KiB

Open AccessArticle

Effect of Foliar Treatment with Aqueous Dispersions of Silver Nanoparticles on Legume-Rhizobium Symbiosis and Yield of Soybean (Glycine max L. Merr.)

by Yurii A. Krutyakov, Maria T. Mukhina, Olga A. Shapoval and Meisam Zargar

Agronomy 2022, 12(6), 1473; https://doi.org/10.3390/agronomy12061473 - 18 Jun 2022

Cited by 5 | Viewed by 1943

Abstract

Interest in the use of silver as a component of plant protection products and growth regulators appeared relatively recently with the development of methods for the effective stabilization of colloidal systems containing nanoparticles of this metal. In the present work, we studied the [...] Read more.

Interest in the use of silver as a component of plant protection products and growth regulators appeared relatively recently with the development of methods for the effective stabilization of colloidal systems containing nanoparticles of this metal. In the present work, we studied the effect of foliar treatments with aqueous dispersions of silver nanoparticles stabilized by polyhexamethylene biguanide hydrochloride with an average diameter of 6 ± 1 nm and a zeta-potential of +47.4 ± 1.3 mV on legume-Rhizobium symbiosis, which largely determines the efficiency of soil nitrogen assimilation and the yield of soybean (Glycine max L. Merr.). Based on the results of a two-year field experiment, it was shown that treatments with low doses of silver nanoparticles lead to a significant increase in the number of root nodules and an increase in soybean yield. The observed biological effectiveness of silver nanoparticles dispersions is explained by an increase in the enzymatic activity of peroxidases and polyphenol oxidases in the terrestrial part of plants. It is very likely that the treatment with silver nanoparticles and the increase in peroxidase activity in non-infected parts of the plant lead to a more effective prevention of the penetration of rhizobacteria into the aboveground soybean organs, which, in turn, may be the reason for the observed decrease in the activity of peroxidase and polyphenol oxidase in parts of plant roots susceptible to rhizobia. The latter, as is known, contributes to an easier flow of the nodulation process and the development of legume–Rhizobium symbiosis. Full article

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

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17 pages, 2357 KiB

Open AccessArticle

Characterizing Root Morphological Traits in 65 Genotypes of Foxtail Millet (Setaria italica L.) from Four Different Ecological Regions in China

by Xiaoxia Yang, Qiaoyan Tian, Jiakun Yan and Yinglong Chen

Agronomy 2022, 12(6), 1472; https://doi.org/10.3390/agronomy12061472 - 18 Jun 2022

Cited by 2 | Viewed by 2128

Abstract

As an indispensable grain crop, foxtail millet (Setaria italica L.) is becoming a functional food in China because of its abundant nutrients. However, low rainfall and uneven precipitation limit its growth and production, especially in northwest China. Understanding the root phenotypic characteristics [...] Read more.

As an indispensable grain crop, foxtail millet (Setaria italica L.) is becoming a functional food in China because of its abundant nutrients. However, low rainfall and uneven precipitation limit its growth and production, especially in northwest China. Understanding the root phenotypic characteristics of foxtail millet is critical for utilizing its root characteristics to breed new millet varieties with improved resource-use efficiency and better adaptation to harsh environments. The present study characterized the variability of the root morphological traits at the seedling stage of 65 millet genotypes selected from four ecological regions across seven provinces in China. The plants were assessed after 21 days of growth in the germination pouches, and 48 root and shoot traits were measured. The results showed a large variation among the genotypes in the growth and functional traits. Among the measured traits, root dry mass, maximal root length, root surface area, and root tissue density contributed the most to the principal components. Root surface area ratio and root volume ratio were significantly correlated with root length ratio, respectively, while root length density and root weight density were negatively correlated with root diameter (p < 0.01). Shoot dry mass, root number, root length, root dry mass, and total dry mass were closely correlated with each other. Root length and root surface area in each 5-cm sections decreased from the top to the bottom along the root system. Among the four ecological regions, genotypes from the early maturing area of northwest China had the greatest root length, shoot dry mass, root dry mass, and root density, while those from the early maturing area of northwest China generally had the largest root system, with about 2.2 times more root length and dry weight than those from the early maturing area of northeast China (the shortest root system). The genotypic variability in root traits and correlations among shoot and root traits form a basis for breeding new millet cultivars. Full article

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15 pages, 308 KiB

Open AccessArticle

Economic Assessment of Irrigation with Desalinated Seawater in Greenhouse Tomato Production in SE Spain

by David Martínez-Granados, Patricia Marín-Membrive and Javier Calatrava

Agronomy 2022, 12(6), 1471; https://doi.org/10.3390/agronomy12061471 - 18 Jun 2022

Cited by 5 | Viewed by 1639

Abstract

This study assesses the impact of irrigating with desalinated seawater (DSW) on the profitability of greenhouse tomato in south-eastern Spain, comparing different water-quality sources in both traditional sanding cultivation and soilless hydroponic production. The assessment is based on the combination of partial crop [...] Read more.

This study assesses the impact of irrigating with desalinated seawater (DSW) on the profitability of greenhouse tomato in south-eastern Spain, comparing different water-quality sources in both traditional sanding cultivation and soilless hydroponic production. The assessment is based on the combination of partial crop budgeting techniques with field data from the LIFE DESEACROP Project experimental activities. Our results show that the exclusive use of DSW for tomato production increases fertilization costs by 20% in soilless systems and by 34% in traditional sanding cultivation, and water costs by 30% in soilless systems and by 48% in traditional soil cultivation. As a result, production costs increase by 5% in soilless cultivation and 3% in soil cultivation, increases that are reduced when DSW is blended with brackish water. However, the lower salinity of DSW, compared with conventional water resources in the area, increases both crop yield and profitability. Soilless cultivation would also increase tomato profitability but only if good quality water is available. The materialization of the potential benefits of soilless production requires improving water quality through the increased use of DSW. Otherwise, the traditional sanding production system, better adapted to the area’s poor soils and bad quality water, would be more profitable. Full article

(This article belongs to the Special Issue Selected Papers from 38th National Irrigation Congress)

11 pages, 2594 KiB

Open AccessArticle

GWAS and Identification of Candidate Genes Associated with Seed Soluble Sugar Content in Vegetable Soybean

by Wenjing Xu, Hui Liu, Songsong Li, Wei Zhang, Qiong Wang, Hongmei Zhang, Xiaoqing Liu, Xiaoyan Cui, Xin Chen, Wei Tang, Yanzhe Li, Yuelin Zhu and Huatao Chen

Agronomy 2022, 12(6), 1470; https://doi.org/10.3390/agronomy12061470 - 18 Jun 2022

Cited by 6 | Viewed by 2374

Abstract

Total soluble sugar (TSS) is an important component in vegetable soybean seeds during the R6 stage and greatly impacts fresh soybean flavor. Increasing the TSS content is thus one of the most important breeding objectives for the creation of high-quality vegetable soybean germplasm. [...] Read more.

Total soluble sugar (TSS) is an important component in vegetable soybean seeds during the R6 stage and greatly impacts fresh soybean flavor. Increasing the TSS content is thus one of the most important breeding objectives for the creation of high-quality vegetable soybean germplasm. To better understand the genetic basis of the TSS at the R6 stage, we investigated 264 germplasm accessions in two environments. We obtained five associations with 27 significant SNPs using GWAS. The significant SNPs S15_10810881–S15_10843821 and S06_12044239–S06_12048607 were identified in both environments. We then conducted candidate gene analysis and uncovered nine candidate genes as potential regulators of TSS content in vegetable soybean seeds using RT-PCR. These genes may be involved in the regulation of soluble sugar content in soybean seeds. This study provides new knowledge for the understanding of the genetic basis of TSS at the R6 stage and will help improve regulation of TSS in vegetable soybean using molecular breeding. Full article

(This article belongs to the Special Issue Frontier Studies in Legumes Genetic Breeding and Production)

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19 pages, 2669 KiB

Open AccessArticle

Genome-Wide Association Mapping Revealed SNP Alleles Associated with Spike Traits in Wheat

by Shamseldeen Eltaher, Ahmed Sallam, Hamdy A. Emara, Ahmed A. Nower, Khaled F. M. Salem, Andreas Börner, P. Stephen Baenziger and Amira M. I. Mourad

Agronomy 2022, 12(6), 1469; https://doi.org/10.3390/agronomy12061469 - 18 Jun 2022

Cited by 10 | Viewed by 2656

Abstract

Wheat (Triticum aestivum L.) is one of the most important crops in the world. Four spike-related traits, namely, spike weight (SW), spike length (SL), the total number of spikelets per spike (TSNS), total kernels per spike (TKNS), and thousand-kernel weight (TKW), were [...] Read more.

Wheat (Triticum aestivum L.) is one of the most important crops in the world. Four spike-related traits, namely, spike weight (SW), spike length (SL), the total number of spikelets per spike (TSNS), total kernels per spike (TKNS), and thousand-kernel weight (TKW), were evaluated in 270 F_3:6 Nebraska winter wheat lines in two environments (Lincoln and North Platte, NE, USA). All genotypes in both locations exhibited high genetic variation for all yield traits. High positive correlations were observed among all yield-related traits in each location separately. No or low correlation in yield-related traits was observed between the two environments. The broad-sense heritability estimates were 72.6, 72.3, 71.2, 72.3, and 56.1% for SW, SL, TSNS, TKNS, and TKW, respectively. A genome-wide association study (GWAS) was used to identify SNPs associated with yield traits. In the Lincoln environment, 44 markers were found to be significantly associated with spike-related traits (SW, SL, TSNS, TKNS, and TKW), while 41 were detected in North Platte. Due to the strong significant genotype x environment, no common SNP markers were found between the two locations. Gene annotation of the significant markers revealed candidate genes encoded for important proteins that are associated directly or indirectly with yield traits. Such high genetic variation among genotypes is very useful for selection to improve yield traits in each location separately. Full article

(This article belongs to the Special Issue Modern Biotechnologies and Improvement Breeding for Cereals Crop)

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17 pages, 3334 KiB

Open AccessArticle

Yield, Flower Quality, and Photo-Physiological Responses of Cut Rose Flowers Grafted onto Three Different Rootstocks in Summer Season

by O-Hyeon Kwon and Hyo-Gil Choi

Agronomy 2022, 12(6), 1468; https://doi.org/10.3390/agronomy12061468 - 18 Jun 2022

Cited by 2 | Viewed by 2256

Abstract

The thermal stress caused by high temperatures on cut rose flowers grown in greenhouses is a major environmental impact that reduces the yield of growing cut rose flowers during summer. To confirm the resistance of grafted cut rose flowers to high-temperature stress, roses [...] Read more.

The thermal stress caused by high temperatures on cut rose flowers grown in greenhouses is a major environmental impact that reduces the yield of growing cut rose flowers during summer. To confirm the resistance of grafted cut rose flowers to high-temperature stress, roses were grown in a greenhouse during the summer season and analyzed for yield, quality, root activity, and photo-physiological characteristics. A morphological change was observed in the stomata of the grafted cut rose flowers, which were larger in size than the scion or rootstocks. As a result of cultivating cut rose flowers by lowering the temperature of the greenhouse through shading in summer, it was confirmed that all of the scions, rootstocks, and grafted cut rose flowers were not in a stressed state by observing the maximal quantum yield of primary photochemistry (F_V/F_M) values on the chlorophyll-a fluorescence. However, the rate of electron transport flux from the primary acceptor (Q_A) to the secondary acceptor (Q_B) per the photosystem II reaction center (ET₀/RC) value was found to be significantly higher on grafted cut rose flowers, compared with that of the scions. The efficiencies of the photosynthesis rate, the transpiration rate, and the stomatal conductance were increased when grafted compared with non-grafted. When the root activity was confirmed by the formazan content, it was found that the root activity was improved grafting. Furthermore, when grafted, morphological changes such as flower size and the number of petals on spray roses were also observed. Although there was a difference depending on the type of rootstock, the yield of the grafted cut rose flowers increased by 11–20%, compared with the scion rose. Therefore, grafting cultivation during the summer season with high temperatures is an effective method in terms of photo-physiological response and yield. Full article

(This article belongs to the Collection Scion-Rootstock Interaction in Horticultural Crops: Physiological and Agronomic Implications)

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14 pages, 2148 KiB

Open AccessArticle

Overexpression of a Thioredoxin-Protein-Encoding Gene, MsTRX, from Medicago sativa Enhances Salt Tolerance to Transgenic Tobacco

by Xinhang Duan, Zhaoyu Wang, Yu Zhang, Han Li, Mei Yang, Hang Yin, Jing Cui, Hua Chai, Yonghang Gao, Guofu Hu and Pan Zhang

Agronomy 2022, 12(6), 1467; https://doi.org/10.3390/agronomy12061467 - 18 Jun 2022

Cited by 9 | Viewed by 1928

Abstract

Thioredoxin (TRX) is a small molecule protein that participates in the redox process and plays a decisive role in various functions of plants. However, the role of TRX in Medicago sativa (alfalfa), a widely cultivated perennial herb of legume, is still poorly understood. [...] Read more.

Thioredoxin (TRX) is a small molecule protein that participates in the redox process and plays a decisive role in various functions of plants. However, the role of TRX in Medicago sativa (alfalfa), a widely cultivated perennial herb of legume, is still poorly understood. Here, we isolated MsTRX from alfalfa and determined the characteristics in improving salt tolerance by assaying the phenotype and physiological changes and the expression of stress-response genes in transgenic tobacco. The expression of MsTRX was similar in alfalfa roots, leaves, and inflorescences, and was downregulated in response to cold, drought, and salt treatment. The overexpression of MsTRX in tobacco promoted the accumulation of soluble sugar (SS) and proline; enhanced the activity of peroxidase (POD); and induced the upregulation of beta-amylase 1 (BAM1), lipid-transfer protein 1 (LTP1), candidate signal molecules/sensor relay proteins (CBSX3), superoxide dismutase [Cu-Zn] (Cu/Zn-SOD), superoxide dismutase [Mn] (Mn-SOD), protein gamma response 1 (GR1), dehydrin DHN1-like (ERD10B), and serine/threonine-protein kinase (SnRK2), as well as the downregulation of phyB activation-tagged suppressor1 (BAS1) and serine/threonine-protein kinase that phosphorylates LHCII protein 7 (STN7) under salt stress. These results indicated that MsTRX improves salt tolerance via maintaining osmotic homeostasis, scavenging reactive oxygen species (ROS), and regulating the transcription of stress-response genes in plants. In our study, we provided a new understanding of how MsTRX improves salt stress in plants and how MsTRX can be included in future breeding programs to improve salt tolerance in alfalfa. Full article

(This article belongs to the Special Issue Advances in Genetics, Breeding, and Quality Traits in Forage and Turf Grass)

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10 pages, 660 KiB

Open AccessCommunication

Essential Oil of Citrus aurantium L. Leaves: Composition, Antioxidant Activity, Elastase and Collagenase Inhibition

by Chahinez Oulebsir, Hakima Mefti-Korteby, Zahr-Eddine Djazouli, Bachar Zebib and Othmane Merah

Agronomy 2022, 12(6), 1466; https://doi.org/10.3390/agronomy12061466 - 18 Jun 2022

Cited by 17 | Viewed by 4098

Abstract

Sour orange (Citrus aurantium L.), which belongs to the Rutaceae family, is used around the Mediterranean Sea for ornamental and agronomic purposes as a rootstock for the Citrus species. Peels and flowers, the most-used parts of Citrus aurantium L., have constituted a largely [...] Read more.

Sour orange (Citrus aurantium L.), which belongs to the Rutaceae family, is used around the Mediterranean Sea for ornamental and agronomic purposes as a rootstock for the Citrus species. Peels and flowers, the most-used parts of Citrus aurantium L., have constituted a largely promising area of research for their many medicinal properties. However, the leaves of sour orange have not yet been studied extensively. The present study aimed at investigating the essential oil composition of sour orange leaves grown in Algeria and determining their antioxidant and anti-inflammatory properties. Essential oil composition of leaves harvested before flowering was determined by GC-MS. Total phenol content, antioxidant activities (DPPH) and elastase and collagenase inhibition were assessed. Forty-three volatile compounds were detected in essential oil from leaves with a yield of 0.57%. The major compounds were linalool, linalyl acetate and α-Terpineol. Results show that the total phenol content and antioxidant activity of essential oil are low, 3.48 ± 0.10 mg/g (Gallic Acid Equivalent/EO) and IC₅₀ > 10,000 mg·L⁻¹, respectively. In contrast, EO present an interesting level of elastase and collagenase inhibition. This result emphasizes the potential interest of the essential oil of sour orange mainly in relation to its anti-aging mechanism. Full article

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

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12 pages, 4397 KiB

Open AccessArticle

Evaluating Sensor-Based Mechanical Weeding Combined with Pre- and Post-Emergence Herbicides for Integrated Weed Management in Cereals

by Marcus Saile, Michael Spaeth and Roland Gerhards

Agronomy 2022, 12(6), 1465; https://doi.org/10.3390/agronomy12061465 - 18 Jun 2022

Cited by 8 | Viewed by 1917

Abstract

Due to the increasing number of herbicide-resistant weed populations and the resulting yield losses, weed control must be given high priority to ensure food security. Integrated weed management (IWM) strategies, including reduced herbicide application, sensor-guided mechanical weed control and combinations thereof are indispensable [...] Read more.

Due to the increasing number of herbicide-resistant weed populations and the resulting yield losses, weed control must be given high priority to ensure food security. Integrated weed management (IWM) strategies, including reduced herbicide application, sensor-guided mechanical weed control and combinations thereof are indispensable to achieve this goal. Therefore, this study examined combinations of pre- and post-emergence herbicide applications with sensor-based harrowing and hoeing in cereals by conducting five field experiments at two locations in Southwestern Germany from 2019 to 2021. Each experiment contained an untreated control and a single post-emergence herbicide treatment as a comparison to these IWM treatments. The effects of the different IWM approaches on weed control efficacy (WCE), crop density, and grain yield were recorded. All experiments were set up in a randomized complete block design with four repetitions. Pre-emergence herbicide application combined with one-time harrowing and subsequent hoeing (Pre-Herb + Harr + Hoe) achieved the highest WCE (100%), followed by an approach of WCE (95%) for two-times hoeing. In contrast, a single pre-emergence herbicide application achieved the worst result with an average WCE of 25%. Grain yield was equal between all treatments in between 6 t ha⁻¹ and 10 t ha⁻¹, except for a single pre-emergence herbicide application, which achieved a 2.5 t ha⁻¹ higher grain yield in winter wheat in 2021 that averaged 11 t ha⁻¹, compared to the combination of Pre-Herb + Harr + Hoe that averaged 8.5 t ha⁻¹. The results showed that it is possible to reduce and replace herbicides while achieving equivalent yield and WCE. Full article

(This article belongs to the Special Issue Robotic Weeding)

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20 pages, 4051 KiB

Open AccessArticle

Comparing a New Non-Invasive Vineyard Yield Estimation Approach Based on Image Analysis with Manual Sample-Based Methods

by Gonçalo Victorino, Ricardo P. Braga, José Santos-Victor and Carlos M. Lopes

Agronomy 2022, 12(6), 1464; https://doi.org/10.3390/agronomy12061464 - 18 Jun 2022

Cited by 4 | Viewed by 1890

Abstract

Manual vineyard yield estimation approaches are easy to use and can provide relevant information at early stages of plant development. However, such methods are subject to spatial and temporal variability as they are sample-based and dependent on historical data. The present work aims [...] Read more.

Manual vineyard yield estimation approaches are easy to use and can provide relevant information at early stages of plant development. However, such methods are subject to spatial and temporal variability as they are sample-based and dependent on historical data. The present work aims at comparing the accuracy of a new non-invasive and multicultivar, image-based yield estimation approach with a manual method. Non-disturbed grapevine images were collected from six cultivars, at three vineyard plots in Portugal, at the very beginning of veraison, in a total of 213 images. A stepwise regression model was used to select the most appropriate set of variables to predict the yield. A combination of derived variables was obtained that included visible bunch area, estimated total bunch area, perimeter, visible berry number and bunch compactness. The model achieved an R² = 0.86 on the validation set. The image-based yield estimates outperformed manual ones on five out of six cultivar data sets, with most estimates achieving absolute errors below 10%. Higher errors were observed on vines with denser canopies. The studied approach has the potential to be fully automated and used across whole vineyards while being able to surpass most bunch occlusions by leaves. Full article

(This article belongs to the Special Issue Agriculture 4.0 as a Sustainability Driver)

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17 pages, 309 KiB

Open AccessArticle

Fall Armyworm Tolerance of Maize Parental Lines, Experimental Hybrids, and Commercial Cultivars in Southern Africa

by Prince M. Matova, Casper N. Kamutando, Dumisani Kutywayo, Cosmos Magorokosho and Maryke Labuschagne

Agronomy 2022, 12(6), 1463; https://doi.org/10.3390/agronomy12061463 - 17 Jun 2022

Cited by 8 | Viewed by 2440

Abstract

Fall armyworm [Spodoptera frugiperda (J./E. Smith); FAW] is negatively impacting sustainable maize production, particularly in smallholder farming systems in sub-Saharan Africa. Two sets of germplasm (commercial cultivars and experimental hybrids, and local and exotic inbred lines) were evaluated under managed and natural [...] Read more.

Fall armyworm [Spodoptera frugiperda (J./E. Smith); FAW] is negatively impacting sustainable maize production, particularly in smallholder farming systems in sub-Saharan Africa. Two sets of germplasm (commercial cultivars and experimental hybrids, and local and exotic inbred lines) were evaluated under managed and natural FAW infestation to identify FAW tolerant material with superior grain yield performance. Significant genotypic effects on foliar FAW damage, ear FAW damage, and grain yield were observed. Commercial cultivars were significantly more affected by FAW infestation than experimental hybrids, as evidenced by high foliar and ear damage scores, yet they out-yielded experimental genotypes. The introduced FAW donor lines (CML338, CML67, CML121, and CML334) showed better tolerance to FAW, individually and in hybrid combinations. Local inbred lines, SV1P, CML491, and CML 539, also showed FAW tolerance. Hybrids and open pollinated varieties were more vulnerable to FAW damage at early growth stages, but they grew out of it through the mid to late whorl stages. Inbred lines showed increasing damage as they grew to maturity. Husk cover, ear rot, anthesis date, and plant height were highly correlated with FAW tolerance. The identified local and exotic lines with FAW tolerance will contribute to FAW resistance breeding in southern Africa. Full article

46 pages, 12244 KiB

Open AccessArticle

Effect of the Airblast Settings on the Vertical Spray Profile: Implementation on an On-Line Decision Aid for Citrus Treatments

by Cruz Garcera, Enrique Moltó, Héctor Izquierdo, Paolo Balsari, Paolo Marucco, Marco Grella, Fabrizio Gioelli and Patricia Chueca

Agronomy 2022, 12(6), 1462; https://doi.org/10.3390/agronomy12061462 - 17 Jun 2022

Cited by 4 | Viewed by 1981

Abstract

Airblast sprayers are widely used for the application of plant protection products (PPP) in citrus. Adaptation of the vertical distribution of the spray cloud to the canopy (density, shape and size), is essential to deposit an adequate amount of PPP on the target [...] Read more.

Airblast sprayers are widely used for the application of plant protection products (PPP) in citrus. Adaptation of the vertical distribution of the spray cloud to the canopy (density, shape and size), is essential to deposit an adequate amount of PPP on the target and to reduce losses (drift, runoff). Vertical spray profiles of three air-assisted axial fan hydraulic sprayers with different configurations and settings were obtained to evaluate the effect of these settings on the vertical spray profile. From the analysis of the empirical results, the impact of operational settings (nozzle, air volume and flow rate) on treatment efficiency is assessed. The empirical database generated in this work has been employed to feed the Citrus VESPA model, a highly intuitive, web-based decision aid tool that helps farmers to easily estimate the vertical spray profiles generated by their particular sprayers and settings and how these influence deposition and potential drift. The tool can also be used to determine the effect and importance of adequately selecting, orienting and opening/closing nozzles and optimizing volume application rate and fan speed, in order to adjust the application to the actual vegetation, with the aim of saving resources and reducing risks to humans and the environment. Full article

(This article belongs to the Special Issue Selected Papers from 11th Iberian Agroengineering Congress)

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27 pages, 7606 KiB

Open AccessEssay

Morphological and Physiological Responses of Melia azedarach Seedlings of Different Provenances to Drought Stress

by Chao Han, Junna Chen, Zemao Liu, Hong Chen, Fangyuan Yu and Wanwen Yu

Agronomy 2022, 12(6), 1461; https://doi.org/10.3390/agronomy12061461 - 17 Jun 2022

Cited by 5 | Viewed by 2110

Abstract

Melia azedarach Linn. is a deciduous tree of the Melia genus in the Meliaceae family that is native to China. To study the mechanism of drought resistance in Melia azedarach and evaluate the drought resistance capacity of each provenance, we selected eight provenances [...] Read more.

Melia azedarach Linn. is a deciduous tree of the Melia genus in the Meliaceae family that is native to China. To study the mechanism of drought resistance in Melia azedarach and evaluate the drought resistance capacity of each provenance, we selected eight provenances (Shandong Kenli, Jiangsu Pizhou, Hubei Shayang, Jiangsu Xuanwu, Jiangxi Xihu, Jiangsu Jurong, Guangdong Luogang, and Henan Shihe) as the research subjects and set four levels of drought stress treatment (CK: 75% of field capacity, mild drought: 60% of field capacity, moderate drought: 45% of field capacity, and severe drought: 30% of field capacity). The results showed that the growth in the seedling height and the ground diameter, the leaf relative water content, transpiration rate (Tr), net photosynthetic rate (Pn), stomatal conductance (Gs), and the content of chlorophyll (Chl) decreased with the increasing stress levels, while the root–shoot ratio, water saturation deficit, and the contents of malondialdehyde (MDA) increased. The SOD in most provenances initially increased and then decreased, reaching a peak during moderate drought. At the late stage of treatment, the magnitude of the changes in the photosynthetic indicators was more pronounced than in the physiological indicators. Principal component analysis showed that the contribution of all four principal components under the three drought stresses was above 85%, which represented the majority of the original data. Combined with the affiliation function method and weights, the comprehensive evaluation value (D value) of the drought resistance was calculated for the eight provenances. Then, we obtained the order of drought resistance of the test materials under the three drought stresses, respectively. The combined results revealed that the drought resistance of Henan Shihe and Jiangxi Xihu was stronger, while the drought resistance of Guangdong Luogang and Hubei Shayang was weaker. Based on the above findings, we can select provenances with strong and weak drought resistance for transcriptome sequencing to screen drought-resistant genes for an in-depth study at the molecular level. Full article

(This article belongs to the Special Issue Advances in Plant Physiology of Abiotic Stresses)

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17 pages, 1137 KiB

Open AccessArticle

Changes in Relationships between Humic Substances and Soil Structure following Different Mineral Fertilization of Vitis vinifera L. in Slovakia

by Vladimír Šimanský, Elżbieta Wójcik-Gront, Jarmila Horváthová, Dorota Pikuła, Tomáš Lošák, Agnieszka Parzych, Martin Lukac and Elena Aydın

Agronomy 2022, 12(6), 1460; https://doi.org/10.3390/agronomy12061460 - 17 Jun 2022

Cited by 7 | Viewed by 1716

Abstract

The quantity and quality of soil organic matter (SOM) depending on many edaphic and environmental factors may change in response to agriculture-related practices. The SOM humification process can be supported by the application of mineral fertilizers, but in the production vineyards, such information [...] Read more.

The quantity and quality of soil organic matter (SOM) depending on many edaphic and environmental factors may change in response to agriculture-related practices. The SOM humification process can be supported by the application of mineral fertilizers, but in the production vineyards, such information is lacking. NPK fertilizer alters the soil quality, and therefore, the aim of this study was to: (1) assess the extent and dynamics of different NPK (control—no fertilization; 1st NPK; and 3rd NPK levels) rates to the soil with grass sward cover in a productive vineyard on changes in SOM, humic substances (HS), and soil structure, and (2) identify relationships between SOM, HS, and soil structure. Results showed that the share of humic acids in soil organic carbon decreased only in NPK1 compared to control and NPK3 treatments. The color quotient of humic substance values in NPK1 and NPK3 increased by 4 and 5%, respectively, compared to control. Over a period of 14 years, the content of soil organic carbon increased by 0.71, 0.69, and 0.53 g kg⁻¹ year⁻¹ in the control, NPK1, and NPK3, respectively. The content of HS increased linearly with slight differences due to NPK application. The vulnerability of the soil structure decreased due to fertilization—more at the higher NPK level. The rate of formed soil crust was decreasing in the following order: control > NPK1 > NPK3. In the control treatment, the relations between SOM, HS, and soil structure were most abundant and with the greatest significance, while with the increasing level of NPK, these relations lost their significance. Full article

(This article belongs to the Special Issue Humic Substances: Importance for Agriculture, Affinity and Interactions with Soil Amendments and Pollutants)

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13 pages, 2265 KiB

Open AccessArticle

Detection of Weeds Growing in Alfalfa Using Convolutional Neural Networks

by Jie Yang, Yundi Wang, Yong Chen and Jialin Yu

Agronomy 2022, 12(6), 1459; https://doi.org/10.3390/agronomy12061459 - 17 Jun 2022

Cited by 14 | Viewed by 2093

Abstract

Alfalfa (Medicago sativa L.) is used as a high-nutrient feed for animals. Weeds are a significant challenge that affects alfalfa production. Although weeds are unevenly distributed, herbicides are broadcast-applied in alfalfa fields. In this research, object detection convolutional neural networks, including Faster [...] Read more.

Alfalfa (Medicago sativa L.) is used as a high-nutrient feed for animals. Weeds are a significant challenge that affects alfalfa production. Although weeds are unevenly distributed, herbicides are broadcast-applied in alfalfa fields. In this research, object detection convolutional neural networks, including Faster R-CNN, VarifocalNet (VFNet), and You Only Look Once Version 3 (YOLOv3), were used to indiscriminately detect all weed species (1-class) and discriminately detect between broadleaves and grasses (2-class). YOLOv3 outperformed other object detection networks in detecting grass weeds. The performances of using image classification networks (GoogLeNet and VGGNet) and object detection networks (Faster R-CNN and YOLOv3) for detecting broadleaves and grasses were compared. GoogLeNet and VGGNet (F₁ scores ≥ 0.98) outperformed Faster R-CNN and YOLOv3 (F₁ scores ≤ 0.92). Classifying and training various broadleaf and grass weeds did not improve the performance of the neural networks for weed detection. VGGNet was the most effective neural network (F₁ scores ≥ 0.99) tested to detect broadleaf and grass weeds growing in alfalfa. Future research will integrate the VGGNet into the machine vision subsystem of smart sprayers for site-specific herbicide applications. Full article

(This article belongs to the Special Issue Agronomic, Technological and Ecological Advances in Integrated Weed Management)

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6 pages, 217 KiB

Open AccessCommunication

Rodents in Agriculture: A Broad Perspective

by Gary Witmer

Agronomy 2022, 12(6), 1458; https://doi.org/10.3390/agronomy12061458 - 17 Jun 2022

Cited by 14 | Viewed by 5848

Abstract

There are thousands of rodent species in the world. While they provide a number of ecosystem functions, unfortunately, some species cause significant damage to agriculture. Rodent damage occurs to crops in the field, but also to stored foods, livestock feed, and structures. There [...] Read more.

There are thousands of rodent species in the world. While they provide a number of ecosystem functions, unfortunately, some species cause significant damage to agriculture. Rodent damage occurs to crops in the field, but also to stored foods, livestock feed, and structures. There are many methods available to reduce rodent populations and/or damage, including both lethal and non-lethal methods. There are advantages and disadvantages to most methods, and many are regulated by federal, state, and local ordinances. Public acceptance of the various methods also varies greatly. Examples and details of these topics are presented in this review. Full article

(This article belongs to the Special Issue Rodents in Crop Production Agricultural Systems)

18 pages, 2448 KiB

Open AccessArticle

Comparative Genetic Diversity Analysis for Biomass Allocation and Drought Tolerance in Wheat

by Kwame W. Shamuyarira, Hussein Shimelis, Isack Mathew, Admire Shayanowako, Rebecca Zengeni and Vincent Chaplot

Agronomy 2022, 12(6), 1457; https://doi.org/10.3390/agronomy12061457 - 17 Jun 2022

Cited by 1 | Viewed by 1854

Abstract

Genetic diversity is invaluable in developing climate-smart and drought-adapted wheat varieties. The aim of this study was to determine the extent of genetic variation present in wheat germplasm collections for biomass allocation and drought tolerance based on complementary phenotypic and root attributes and [...] Read more.

Genetic diversity is invaluable in developing climate-smart and drought-adapted wheat varieties. The aim of this study was to determine the extent of genetic variation present in wheat germplasm collections for biomass allocation and drought tolerance based on complementary phenotypic and root attributes and high-density single nucleotide polymorphism (SNP) markers to select breeding parents. A total of 97 bread wheat (Triticum aestivum L.) genotypes were evaluated in field and greenhouse trials under drought-stressed and non-stressed conditions. The molecular variance analysis showed that the intrapopulation variance was very high at 99%, with a small minimal inter-population variance (1%). The genetic distance, polymorphic information content and expected heterozygosity were 0.20–0.88, 0.24–1.00 and 0.29–0.58, respectively. The cluster analysis based on SNP data showed that 44% and 28% of the assessed genotypes maintained their genetic groups when compared to hierarchical clusters under drought-stressed and non-stressed phenotypic data, respectively. The joint analysis using genotypic and phenotypic data resolved three heterotic groups and allowed the selection of genotypes BW140, BW152, BW157, BW162, LM30, LM47, LM48, LM52, LM54 and LM70. The selected genotypes were the most genetically divergent with high root biomass and grain yield and are recommended for production or breeding. Full article

(This article belongs to the Topic Plant Breeding, Genetics and Genomics)

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21 pages, 1674 KiB

Open AccessReview

Modern Use of Bryophytes as a Source of Secondary Metabolites

by Michał Dziwak, Katarzyna Wróblewska, Antoni Szumny and Renata Galek

Agronomy 2022, 12(6), 1456; https://doi.org/10.3390/agronomy12061456 - 17 Jun 2022

Cited by 9 | Viewed by 4760

Abstract

Bryophytes constitute a heterogeneous group of plants which includes three clades: approximately 14,000 species of mosses (Bryophyta), 6000 species of liverworts (Marchantiophyta), and 300 species of hornworts (Anthocerotophyta). They are common in almost all ecosystems, where they play important roles. Bryophytes lack developed [...] Read more.

Bryophytes constitute a heterogeneous group of plants which includes three clades: approximately 14,000 species of mosses (Bryophyta), 6000 species of liverworts (Marchantiophyta), and 300 species of hornworts (Anthocerotophyta). They are common in almost all ecosystems, where they play important roles. Bryophytes lack developed physical barriers, yet they are rarely attacked by herbivores or pathogens. Instead, they have acquired the ability to produce a wide range of secondary metabolites with diverse functions, such as phytotoxic, antibacterial, antifungal, insect antifeedant, and molluscicidal activities. Secondary metabolites in bryophytes can also be involved in stress tolerance, i.e., in UV-absorptive and drought- and freezing-tolerant activities. Due to these properties, for centuries bryophytes have been used to combat health problems in many cultures on different continents. Currently, scientists are discovering new, unique compounds in bryophytes with potential for practical use, which, in the age of drug resistance, may be of considerable importance. The aim of this review is to present bryophytes as a potential source of compounds with miscellaneous possible uses, with a focus on volatile compounds and antibacterial, antifungal, and cytotoxic potential, and as sources of materials for further promising research. The paper also briefly refers to the methods of compound extraction and acquisition. Formulas of compounds were drawn by the authors using ChemDraw software (PerkinElmer, Boston, MA, USA) with reference to data published in various papers, the ACD/Labs dictionary database, PubChem, and Scopus. The data were gathered in February 2022. Full article

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

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15 pages, 1994 KiB

Open AccessArticle

Analysis of Nitrogen Uptake in Winter Wheat Using Sensor and Satellite Data for Site-Specific Fertilization

by Matthias Stettmer, Franz-Xaver Maidl, Jürgen Schwarzensteiner, Kurt-Jürgen Hülsbergen and Heinz Bernhardt

Agronomy 2022, 12(6), 1455; https://doi.org/10.3390/agronomy12061455 - 17 Jun 2022

Cited by 6 | Viewed by 2322

Abstract

Sensor- and satellite-based determination of nitrogen uptake provides critical data in site-specific fertilization algorithms. Therefore, two basic noncontact measurement methods (sensor and satellite) were investigated in winter wheat, and their precision was evaluated in this study. Nitrogen uptake at four characteristic growth stages [...] Read more.

Sensor- and satellite-based determination of nitrogen uptake provides critical data in site-specific fertilization algorithms. Therefore, two basic noncontact measurement methods (sensor and satellite) were investigated in winter wheat, and their precision was evaluated in this study. Nitrogen uptake at four characteristic growth stages (BBCH 31, BBCH 39, BBCH 55, and BBCH 65) was determined using algorithms based on sensor and satellite data. As a reference, nitrogen uptake was determined using biomass samples in the laboratory (ground truth data). The precision of the tested methods was evaluated using statistical indicators (mean, median, minimum, maximum, and standard deviation) and correlation analyses between the nitrogen uptake of the ground truth data and that of the respective method. The results showed moderate to strong correlations with the nitrogen uptake of the ground truth data for both methods (R² = 0.57–0.83). Both sensor and satellite data best represented nitrogen uptake in BBCH 39 and 55 (R² = 0.63–0.83). In sum, there were only slight deviations in the absolute amount of nitrogen uptake (≤±15%). Clear deviations can be explained by external influences during measurement. Overall, the investigations showed that the nitrogen uptake could be appropriately determined as a data basis for site-specific fertilization systems using sensor and satellite data. Full article

(This article belongs to the Special Issue Nitrogen Cycle in Farming Systems)

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14 pages, 3150 KiB

Open AccessArticle

Variability of Bioactive Substances in Potatoes (Solanum Tuberosum L.) Depending on Variety and Maturity

by Hana Franková, Janette Musilová, Július Árvay, Ľuboš Harangozo, Marek Šnirc, Alena Vollmannová, Judita Lidiková, Alžbeta Hegedűsová and Edina Jaško

Agronomy 2022, 12(6), 1454; https://doi.org/10.3390/agronomy12061454 - 17 Jun 2022

Cited by 8 | Viewed by 1749

Abstract

Potatoes (Solanum tuberosum L.) are an essential food for the human diet and thus represent an important source of biologically active substances. This study aimed at investigating the content of bioactive substances (total anthocyanin and polyphenol contents and chlorogenic acid) in seven [...] Read more.

Potatoes (Solanum tuberosum L.) are an essential food for the human diet and thus represent an important source of biologically active substances. This study aimed at investigating the content of bioactive substances (total anthocyanin and polyphenol contents and chlorogenic acid) in seven potato varieties (Belana, Cecile, Magenta Love, Mozart, Talentine, Toscana, and Violet Queen) with various flesh and skin colors. To evaluate the impact of potato maturity on the analyzed parameters, potato samples were harvested in two different periods (1st harvest—July and 2nd harvest—September). Total anthocyanin and polyphenol contents were determined spectrophotometrically, and chlorogenic acid by the HPLC-DAD method. Varieties with a colored flesh (Magenta Love and Violet Queen) showed the highest content of bioactive substances. The maturity level significantly (p < 0.05) affected the total content of anthocyanins and polyphenols in potatoes. Early to medium early varieties (Belana and Magenta Love) showed an increase in chlorogenic acid content during maturation, while in other varieties, chlorogenic acid decreased due to higher maturity. In terms of the content of bioactive substances with a possible positive effect on human health, the consumption of potatoes with colored flesh could be recommended. Full article

(This article belongs to the Special Issue Bioactive Substances with Antioxidant Properties in Agricultural Products)

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12 pages, 1043 KiB

Open AccessArticle

Effect of Wheat Monoculture on Durum Wheat Yield under Rainfed Sub-Humid Mediterranean Climate of Tunisia

by Asma Bouatrous, Kalthoum Harbaoui, Chahine Karmous, Samia Gargouri, Amir Souissi, Karima Belguesmi, Hatem Cheikh Mhamed, Mohamed Salah Gharbi and Mohamed Annabi

Agronomy 2022, 12(6), 1453; https://doi.org/10.3390/agronomy12061453 - 17 Jun 2022

Cited by 8 | Viewed by 2513

Abstract

Cultivating cereals in monoculture systems contributes to the decrease in grain yield and quality. Currently, under Mediterranean climate conditions of Tunisia, wheat mono-cropping covers more than 70% of cereal areas. In order to reveal the impact of this practice on cereal productivity, five [...] Read more.

Cultivating cereals in monoculture systems contributes to the decrease in grain yield and quality. Currently, under Mediterranean climate conditions of Tunisia, wheat mono-cropping covers more than 70% of cereal areas. In order to reveal the impact of this practice on cereal productivity, five improved durum wheat cultivars (Karim, Khiar, Om Rabiaa, Razzek, and Maali) were conducted under two conditions of previous wheat crop: one-year wheat previous crop (W) and two successive years (W-W). Then, they were assessed for grain yield (GY), yield components (NKS, TKW, NS), straw yield, harvest index (SY, HI), and grain quality parameters during three consecutive cropping seasons (2017, 2018, and 2019). The results showed significant effects of cropping season for all measured parameters, except thousand kernel weight (TKW). A significant effect (p < 0.05) of Pre-Crop was observed on yield components. However, grain yield (GY) was improved after one-year wheat Pre-Crop (W) (4082.3 kg ha⁻¹) more than after two years (W-W) (3277.3 kg ha⁻¹). Our results show that, based on the three-year experiment, almost all yield related traits were significantly affected by the genotype except HI and NS. The highest GYs were recorded for Om Rabiaa (4010.4 kg ha⁻¹) and Nasr (3765.76 kg ha⁻¹). All grain quality was significantly (p < 0.05) affected by cropping season, but only gluten content (GC) and vitreousness aspect (Vit A) were affected by genotype. On the other hand, the Pre-Crop W-W decreased grain protein concentration (GPC) (12.13%) and GC (22.14%) but no significant effect was observed on the Vit A of grain in our study. Furthermore, GY was positively correlated with HI (r = 0.64), NKS (r = 0.59), SN (r = 0.49), GPC (r = 0.23), and GC (r = 0.23). According to stability analysis, the Karim cultivar is the most stable genotype in wheat mono-cropping for GY and straw yield (SY). Altogether, this study provides useful information for farmers on how to produce a satisfactory yield for durum wheat cultivation under mono-cropping wheat conditions in the sub-humid environment of the Mediterranean climate of Tunisia. Full article

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Agronomy, Volume 12, Issue 6 (June 2022) – 236 articles

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