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Agronomy, Volume 10, Issue 12 (December 2020) – 177 articles

Cover Story (view full-size image): Magnolias are popular as ornamental garden plants and are prized worldwide for their exquisite flowers. The yellow pigmentation in magnolias is derived from a single American species, Magnolia acuminata L. or M. acuminata var. subcordata. Hybridization with Chinese magnolias (M. denudata, M. liliflora, or M. stellata) can offer a yellow flower color and a range of tree sizes and shapes. Despite more than 50 years of selection, many cultivars of yellow-flowering magnolias are unavailable. This is due to the recalcitrance in propagation, nor similar respond to a single method of propagation. The aim of this study was to analyze the profile of endogenous phenolic acids in yellow-flowered magnolias and to evaluate their effects on the in vitro rooting. A relationship between the overaccumulation of chlorogenic acid and coumaric acid and the low rooting responses has been found. View this paper
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20 pages, 2079 KiB  
Article
Andean Lupin Phenology and Agronomic Performance under Different Planting Dates in a Mediterranean Climate
by Efstathia Lazaridi, George K. Papadopoulos and Penelope J. Bebeli
Agronomy 2020, 10(12), 2020; https://doi.org/10.3390/agronomy10122020 - 21 Dec 2020
Cited by 4 | Viewed by 3120
Abstract
Andean lupin in Europe has regained interest in recent years due to its high seed protein and oil content and its potential use for food, feed as well as a crop used in biorefineries. A search for suitable germplasm in combination with a [...] Read more.
Andean lupin in Europe has regained interest in recent years due to its high seed protein and oil content and its potential use for food, feed as well as a crop used in biorefineries. A search for suitable germplasm in combination with a determination of appropriate agronomical practices such as planting date are needed for commercial farming in new areas. The current study aims to evaluate the performance of six selected L. mutabilis accessions in a Mediterranean area using two different planting dates for two consecutive experimental years. A split plot design with accessions as subplots and planting dates as main plots was used. Measurements such as days to flowering, plant height, total number of pods and seeds per plant, seed yield and seed crude protein content were taken. All accessions performed better when cultivation started not later than the end of autumn since high temperatures occurred during late spring shortened the growth cycle and reduced yield. Earlier cultivation applied, in the middle of autumn, did not enhance significantly seed yield production. Among the accessions, LIB223 was characterized by the highest seed crude protein content in the early planting treatment, while accessions with prolonged growth cycle (LIB209, LIB214 and LIB223) produced higher seed yield than other accessions and could be further studied as promising breeding material for cultivation under the edaphoclimatic conditions tested. Full article
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29 pages, 4448 KiB  
Article
Crop and Residue Management Improves Productivity and Profitability of Rice–Maize System in Salt-Affected Rainfed Lowlands of East India
by Sukanta K. Sarangi, Sudhanshu Singh, Ashish K. Srivastava, Madhu Choudhary, Uttam K. Mandal, Tashi D. Lama, Kshirendra K. Mahanta, Virender Kumar, Parbodh C. Sharma and Abdelbagi M. Ismail
Agronomy 2020, 10(12), 2019; https://doi.org/10.3390/agronomy10122019 - 21 Dec 2020
Cited by 3 | Viewed by 3477
Abstract
This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farmers most commonly grow tall rice varieties in the wet season to cope with flash and/or stagnant floods, leading to large amounts of rice residue production. Most of the [...] Read more.
This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farmers most commonly grow tall rice varieties in the wet season to cope with flash and/or stagnant floods, leading to large amounts of rice residue production. Most of the land remains fallow during the dry season because of increased salinity and scarcity of freshwater for irrigation. The study aims to provide options for increasing cropping intensity through management of crop residues (CR) and soil salinity, conservation of soil moisture, and reduction in production cost. The rice–maize rotation was assessed with rice as the main plot as (1) puddled transplanted rice (PTR) with CR of both rice and maize removed, (2) PTR and 40% CR of both crops retained, (3) dry direct-seeded rice (DSR) with CR of both crops removed, and (4) DSR with 40% CR of both crops retained. Maize in the dry season was supplied with different N levels as sub-plots—control (0 kg N ha−1), 80, 120, and 160 kg N ha−1. DSR, when combined with CR retention (DSR + R), reduced soil salinity. The increase in rice grain yield with CR retention (observed in second and third years) and crop establishment (higher in DSR versus PTR in the third year) was 16 and 24%, respectively. The cost of production increased by 17% (USD 605 ha−1) in PTR compared with DSR (USD 518 ha−1). CR retention reduced irrigation water requirement by 37% and N requirement by 40 kg ha−1 for hybrid maize. When CR was removed (−R), the N requirement for hybrid maize increased to 160 kg N ha−1 compared to when it was partially (40%) retained, where the requirement was 120 kg ha−1 with similar yields. Available N was highest under DSR + R (314 kg ha−1) and lowest under PTR − R (169 kg ha−1), and it also increased with increasing N application up to 120 kg ha−1 (+R) and 160 kg ha−1 (−R). The results of the study hold promise for increasing cropping intensity and farmers’ incomes, with broader implications for increasing productivity on about 2.95 million hectares currently under a rice–fallow system in eastern India, and in coastal areas affected by similar conditions in South and Southeast Asia. Full article
(This article belongs to the Special Issue Crop Mineral Nutrition: Old and Emerging Challenges and Opportunities)
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37 pages, 14048 KiB  
Article
Canopy Structure and Photosynthetic Performance of Irrigated Cassava Genotypes Growing in Different Seasons in a Tropical Savanna Climate
by Supranee Santanoo, Kochaphan Vongcharoen, Poramate Banterng, Nimitr Vorasoot, Sanun Jogloy, Sittiruk Roytrakul and Piyada Theerakulpisut
Agronomy 2020, 10(12), 2018; https://doi.org/10.3390/agronomy10122018 - 21 Dec 2020
Cited by 6 | Viewed by 4309
Abstract
Growth and photosynthesis performance of cassava during early vegetative growth are important determinants of final biomass. The objective of this work was to investigate canopy structure and photosynthesis performance of four cassava genotypes (Rayong 9, Rayong 11, Kasetsart 50, and CMR38-125-77) growing under [...] Read more.
Growth and photosynthesis performance of cassava during early vegetative growth are important determinants of final biomass. The objective of this work was to investigate canopy structure and photosynthesis performance of four cassava genotypes (Rayong 9, Rayong 11, Kasetsart 50, and CMR38-125-77) growing under irrigation at 3 and 6 months after planting (3MAP and 6MAP). Data for the 3MAP plants were collected from cassava planted on 30 June (Rainy PD), 10 November (Cool PD1), and 15 December (Cool PD2) 2015; and for the 6MAP from those planted on 20 April 2015 (Hot PD), Rainy PD, and Cool PD1. The plants growing in the rainy season had significantly higher leaf area index (LAI) than those growing in the cool and hot seasons. Consequently, they had lower percentage light penetration at the bottom of canopy, and therefore more light interception through the canopy, and hence a higher mean net photosynthesis rate (Pn) across the six canopy levels. At the 3MAP, which is the stage of maximum rate of leaf and stem growth, the Rainy PD and Cool PD2 plants of CMR38-125-77 showed the highest LAI and highest mean Pn. Similarly, the Cool PD1 plants of Kasetsart 50 showed the highest LAI and highest mean Pn. In contrast, at 6MAP during the stage of active starch accumulation in storage roots, the genotypes with the highest mean Pn were the ones having an intermediate (CMR38-125-77 for the Hot PD) or low LAI (Rayong 9 for the Rainy PD, and CMR38-125-77 for the Cool PD1). Data on variations in canopy structure and photosynthesis potentials of different cassava genotypes in response to seasonal variations may be useful for crop growth modeling and may be employed as a criterion for the selection of suitable genotypes for each growing season. Full article
(This article belongs to the Section Innovative Cropping Systems)
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14 pages, 1395 KiB  
Article
Growth, Rhizosphere Carboxylate Exudation, and Arbuscular Mycorrhizal Colonisation in Temperate Perennial Pasture Grasses Varied with Phosphorus Application
by Sangay Tshewang, Zed Rengel, Kadambot H. M. Siddique and Zakaria M. Solaiman
Agronomy 2020, 10(12), 2017; https://doi.org/10.3390/agronomy10122017 - 21 Dec 2020
Cited by 8 | Viewed by 2010
Abstract
Phosphorus (P) fertiliser is applied regularly to the nutrient-poor sandy soils in southwestern Australia to elevate and/or maintain pasture production. This study aimed to characterise differential growth, root carboxylate exudation, and mycorrhizal responses in three temperate perennial pasture grasses at variable P supply. [...] Read more.
Phosphorus (P) fertiliser is applied regularly to the nutrient-poor sandy soils in southwestern Australia to elevate and/or maintain pasture production. This study aimed to characterise differential growth, root carboxylate exudation, and mycorrhizal responses in three temperate perennial pasture grasses at variable P supply. Tall fescue (Festuca arundinacea L. cv. Prosper), veldt grass (Ehrharta calycina Sm. cv. Mission), and tall wheatgrass (Thinopyrum ponticum L. cv. Dundas) with five P rates varying from 0 to 100 mg P kg−1 soil were evaluated in a controlled environment. Rhizosphere carboxylate exudation and mycorrhizal colonisation were assessed. Veldt grass produced the maximum shoot dry weight, highest agronomic phosphorus-use efficiency at low P supply, as well as the highest specific root length and shoot P content at all P rates. Across species, the maximum shoot weight was obtained at 20 and 50 mg P kg−1 soil, which differed significantly from the two lowest P rates (0 and 5 mg P kg−1 soil). Phosphorus application influenced carboxylate exudation, with plants exuding acetate only in the zero P treatment, and citrate and malonate in the P-supplemented treatments. In all three species, acetate and malonate were the major carboxylates exuded (37–51% of the total). Only tall wheatgrass released trans-aconitate. Citrate and malonate concentrations in the rhizosphere increased with P supply, suggesting their important role in P acquisition. Phosphorus applications reduced arbuscular mycorrhizal colonisation and increased root diameter as the P rate increased. Root carboxylate exudation in low-P soil played a role in mobilisation of P via P solubilisation, but the role of exuded carboxylate in soils well supplied with P might be diminished. Full article
(This article belongs to the Special Issue Perception and Acquisition of Nutrients in Cultivated Plants)
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18 pages, 3023 KiB  
Article
Monitoring Grassland Management Effects on Soil Organic Carbon—A Matter of Scale
by Alexandra Crème, Cornelia Rumpel, Sparkle L. Malone, Nicolas P. A. Saby, Emmanuelle Vaudour, Marie-Laure Decau and Abad Chabbi
Agronomy 2020, 10(12), 2016; https://doi.org/10.3390/agronomy10122016 - 21 Dec 2020
Cited by 13 | Viewed by 3417
Abstract
Introduction of temporary grasslands into cropping cycles could be a sustainable management practice leading to increased soil organic carbon (SOC) to contribute to climate change adaption and mitigation. To investigate the impact of temporary grassland management practices on SOC storage of croplands, we [...] Read more.
Introduction of temporary grasslands into cropping cycles could be a sustainable management practice leading to increased soil organic carbon (SOC) to contribute to climate change adaption and mitigation. To investigate the impact of temporary grassland management practices on SOC storage of croplands, we used a spatially resolved sampling approach combined with geostatistical analyses across an agricultural experiment. The experiment included blocks (0.4- to 3-ha blocks) of continuous grassland, continuous cropping and temporary grasslands with different durations and N-fertilizations on a 23-ha site in western France. We measured changes in SOC storage over this 9-year experiment on loamy soil and investigated physicochemical soil parameters. In the soil profiles (0–90 cm), SOC stocks ranged from 82.7 to 98.5 t ha−1 in 2005 and from 81.3 to 103.9 t ha−1 in 2014. On 0.4-ha blocks, the continuous grassland increased SOC in the soil profile with highest gains in the first 30 cm, while losses were recorded under continuous cropping. Where temporary grasslands were introduced into cropping cycles, SOC stocks were maintained. These observations were only partly confirmed when changing the scale of observation to 3-ha blocks. At the 3-ha scale, most grassland treatments exhibited both gains and losses of SOC, which could be partly related to soil physicochemical properties. Overall, our data suggest that both management practices and soil characteristics determine if carbon will accumulate in SOC pools. For detailed understanding of SOC changes, a combination of measurements at different scales is necessary. Full article
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18 pages, 4149 KiB  
Article
A Strip-Till One-Pass System as a Component of Conservation Agriculture
by Iwona Jaskulska, Kestutis Romaneckas, Dariusz Jaskulski and Piotr Wojewódzki
Agronomy 2020, 10(12), 2015; https://doi.org/10.3390/agronomy10122015 - 21 Dec 2020
Cited by 10 | Viewed by 3063
Abstract
Conservation agriculture has three main pillars, i.e., minimum tillage, permanent soil cover, and crop rotation. Covering the soil surface with plant residues and minimum mechanical soil disturbance can all result from introducing a strip-till one-pass (ST-OP) system. The aim of this study was [...] Read more.
Conservation agriculture has three main pillars, i.e., minimum tillage, permanent soil cover, and crop rotation. Covering the soil surface with plant residues and minimum mechanical soil disturbance can all result from introducing a strip-till one-pass (ST-OP) system. The aim of this study was to determine the impact of the ST-OP technology on the management of plant residues, soil properties, inputs, and emissions related to crop cultivation. We compared the effect of a ST-OP system against conventional tillage (CT) using a plough, and against reduced, non-ploughing tillage (RT). Four field experiments were conducted for evaluating the covering of soil with plant residues of the previous crop, soil loss on a slope exposed to surface soil runoff, soil structure and aggregate stability, occurrence of soil organisms and glomalin content, soil moisture and soil water reserve during plant sowing, labour and fuel inputs, and CO2 emissions. After sowing plants using ST-OP, 62.7–82.0% of plant residues remained on the soil surface, depending on the previous crop and row spacing. As compared with CT, the ST-OP system increased the stability of soil aggregates of 0.25–2.0 mm diameter by 12.7%, glomalin content by 0.08 g·kg−1, weight of earthworms five-fold, bacteria and fungi counts, and moisture content in the soil; meanwhile, it decreased soil loss by 2.57–6.36 t·ha−1 year−1, labour input by 114–152 min·ha−1, fuel consumption by 35.9–45.8 l·ha−1, and CO2 emissions by 98.7–125.9 kg·ha−1. Significant favourable changes, as compared with reduced tillage (RT), were also found with respect to the stability index of aggregates of 2.0–10.0 mm diameter, the number and weight of earthworms, as well as bacteria and fungi counts. Full article
(This article belongs to the Special Issue Conservation Tillage in Sustainable Agro-Ecosystems)
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13 pages, 995 KiB  
Article
Blackcurrant Variety Specific Growth and Yield Formation as a Response to Foliar Fertilizers
by Sorin Vâtcă, Roxana Vidican, Ștefania Gâdea, Melinda Horvat, Anamaria Vâtcă, Valentina Ancuța Stoian and Vlad Stoian
Agronomy 2020, 10(12), 2014; https://doi.org/10.3390/agronomy10122014 - 21 Dec 2020
Cited by 11 | Viewed by 2465
Abstract
Recently, there has been a growing interest in supplementing plant nutrition with foliar fertilizers. Foliar application of nutrients is considered a promising environmentally friendly strategy for improving the yield and nutrient efficiency of crops. Little work with foliar appliances on perennial fruits bushes, [...] Read more.
Recently, there has been a growing interest in supplementing plant nutrition with foliar fertilizers. Foliar application of nutrients is considered a promising environmentally friendly strategy for improving the yield and nutrient efficiency of crops. Little work with foliar appliances on perennial fruits bushes, blackcurrant (Ribes nigrum L.), respectively, has been reported. This study was conducted to evaluate the growth and yield response of three blackcurrant varieties to macro and micronutrients’ foliar fertilizer solutions. Principal component analysis and factors environmental fitting were performed for the global assessment of growth and increases in branches length responsible for yield production throughout the entire vegetation period and reported to the final development. The results endorsed the benefits of foliar fertilization. Each variety has a preference for a specific foliar treatment. The highest increases in branches length for Ruben variety was with Ascovigor foliar fertilizer; for Tiben with Kombimax; for Tines with Mikromix. The varieties growth dynamics due to fertilizers was best fitted to foliar Kombimax. Stable models were found to all blackcurrant varieties depending on developmental stage and foliar fertilization application. Application of foliar fertilizer is very profitable in terms of pairing each variety with optimum product, which will increase its specific yield potential. Full article
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15 pages, 2130 KiB  
Article
Salicylic Acid Improves Boron Toxicity Tolerance by Modulating the Physio-Biochemical Characteristics of Maize (Zea mays L.) at an Early Growth Stage
by Muhammad Nawaz, Sabtain Ishaq, Hasnain Ishaq, Naeem Khan, Naeem Iqbal, Shafaqat Ali, Muhammad Rizwan, Abdulaziz Abdullah Alsahli and Mohammed Nasser Alyemeni
Agronomy 2020, 10(12), 2013; https://doi.org/10.3390/agronomy10122013 - 21 Dec 2020
Cited by 23 | Viewed by 3035
Abstract
The boron (B) concentration surpasses the plant need in arid and semi-arid regions of the world, resulting in phyto-toxicity. Salicylic acid (SA) is an endogenous signaling molecule responsible for stress tolerance in plants and is a potential candidate for ameliorating B toxicity. In [...] Read more.
The boron (B) concentration surpasses the plant need in arid and semi-arid regions of the world, resulting in phyto-toxicity. Salicylic acid (SA) is an endogenous signaling molecule responsible for stress tolerance in plants and is a potential candidate for ameliorating B toxicity. In this study, the effects of seed priming with SA (0, 50, 100 and 150 µM for 12 h) on the growth, pigmentation and mineral concentrations of maize (Zea mays L.) grown under B toxicity were investigated. One-week old seedlings were subjected to soil spiked with B (0, 15 and 30 mg kg−1 soil) as boric acid. Elevating concentrations of B reduced the root and shoot length, but these losses were significantly restored in plants raised from seeds primed with 100 µM of SA. The B application decreased the root and shoot fresh/dry biomasses significantly at 30 mg kg−1 soil. The chlorophyll and carotenoid contents decreased with increasing levels of B, while the contents of anthocyanin, H2O2, ascorbic acid (ASA) and glycinebetaine (GB) were enhanced. The root K and Ca contents were significantly increased, while a reduction in the shoot K contents was recorded. The nitrate concentration was significantly higher in the shoot as compared to the root under applied B toxic regimes. However, all of these B toxicity effects were diminished with 100 µM SA applications. The current study outcomes suggested that the exogenously applied SA modulates the response of plants grown under B toxic conditions, and hence could be used as a plant growth regulator to stimulate plant growth and enhance mineral nutrient uptake under B-stressed conditions. Full article
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21 pages, 2416 KiB  
Article
Characterization and Evaluation of Salvia hispanica L. and Salvia columbariae Benth. Varieties for Their Cultivation in Southwestern Germany
by Samantha Jo Grimes, Filippo Capezzone, Peteh Mehdi Nkebiwe and Simone Graeff-Hönninger
Agronomy 2020, 10(12), 2012; https://doi.org/10.3390/agronomy10122012 - 21 Dec 2020
Cited by 5 | Viewed by 3703
Abstract
Rising consumer attraction towards superfoods and the steadily increasing demand for healthy, environmentally sustainable, and regionally produced food products has sharpened the demand for chia. Over the course of 4 years, two early flowering chia varieties belonging to Salvia hispanica L., and Salvia [...] Read more.
Rising consumer attraction towards superfoods and the steadily increasing demand for healthy, environmentally sustainable, and regionally produced food products has sharpened the demand for chia. Over the course of 4 years, two early flowering chia varieties belonging to Salvia hispanica L., and Salvia columbariae Benth. Species were identified to complete their phenological development and, therefore, able to reach maturity under a photoperiod >12 h, thus enabling the cultivation of chia in central Europe—more specifically, in southwestern Germany—consistently for the first time. Results obtained by the conducted field trial in 2018 showed that chia seed yields and thousand-seed mass ranged from 284.13 to 643.99 kg ha−1 and 0.92 to 1.36 g, respectively. Further, the statistical analyses showed that the protein content of the cultivated chia varieties ranged from 22.14 to 27.78%, the mucilage content varied from 10.35 to 20.66%, and the crude oil content amounted up to 28.00 and 31.73%. Fatty acid profiles were similar to previously reported data with α-Linolenic acid being the most prominent one, ranging from 60.40 to 65.87%, and we obtained ω6:ω3 ratios between 0.2 and 0.3. In conclusion, chia could represent a promising raw material from a nutritional point of view, while being able to diversify the local food basis of southwestern Germany. Full article
(This article belongs to the Special Issue New Plant Sources of Healthy Oil)
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12 pages, 976 KiB  
Article
The Influence of Various Forms of Nitrogen Fertilization and Meteorological Factors on Nitrogen Compounds in Soil under Laboratory Conditions
by Rūta Dromantienė, Irena Pranckietienė, Darija Jodaugienė and Aurelija Paulauskienė
Agronomy 2020, 10(12), 2011; https://doi.org/10.3390/agronomy10122011 - 20 Dec 2020
Cited by 6 | Viewed by 2226
Abstract
Nitrogen is one of the main factors that shapes soil fertility and the productivity of crops, although its abundance can also cause damage to the environment. The aim of this study is to evaluate the influences of different forms of nitrogen fertilizers, soil [...] Read more.
Nitrogen is one of the main factors that shapes soil fertility and the productivity of crops, although its abundance can also cause damage to the environment. The aim of this study is to evaluate the influences of different forms of nitrogen fertilizers, soil temperature, and precipitation on the changes of nitrogen compounds (N-NH4+, N-NO3, and Nmin) in two soil layers. Two pot experiments are performed, involving simulated precipitation levels of 10- and 20 mm. Urea and ammonium nitrate fertilizers are used for fertilization. The soil samples are stored in pots in a climate chamber at different temperatures of 5, 10, 15, and 20 °C. After seven days, the changes of nitrogen compounds (N-NH4+, N-NO3, and Nmin) in 0–15 and 15–30 cm soil layers are analyzed. This study shows that the amount of N-NH4+ nitrogen in the soil depends on the fertilizer form and soil temperature. In the temperature range of 5–20 °C, significantly more N-NH4+ nitrogen is present in urea-fertilized soil. The migration of N-NH4+ into the deeper 15–30 cm soil layer at both the 10- and 20-mm simulated precipitation levels is negligible. The N-NO3 contents in the 0–15 cm soil layer in the temperature range of 5–20 °C are 1.7–2.3 times lower in the urea-fertilized soil than in the ammonium nitrate-fertilized soil at a 10-mm simulated precipitation level and 1.6–2.2 times lower at 20 mm. The Nmin contents in soil are directly dependent on the fertilizer form and soil temperature for both levels of simulated precipitation. Full article
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16 pages, 3324 KiB  
Article
Structure Stability of Cultivated Soils from Semi-Arid Region: Comparing the Effects of Land Use and Anionic Polyacrylamide Application
by Amrakh I. Mamedov, Atsushi Tsunekawa, Mitsuru Tsubo, Haruyuki Fujimaki, Imanverdi Ekberli, Cevdet Şeker, Hasan S. Öztürk, Artemi Cerdà and Guy J. Levy
Agronomy 2020, 10(12), 2010; https://doi.org/10.3390/agronomy10122010 - 20 Dec 2020
Cited by 4 | Viewed by 2645
Abstract
The Sustainable Development Goals of the United Nations call for applying soil management practices that contribute land degradation neutrality. Our objectives were to investigate the effect of (i) soil management—conventional tillage (CT under crop) and no-tillage (NT under grass)—and (ii) an amendment (polyacrylamide [...] Read more.
The Sustainable Development Goals of the United Nations call for applying soil management practices that contribute land degradation neutrality. Our objectives were to investigate the effect of (i) soil management—conventional tillage (CT under crop) and no-tillage (NT under grass)—and (ii) an amendment (polyacrylamide (PAM)) application on the structure stability indices of soils from a semi-arid region. Two sets of experiments were conducted using the high-energy moisture characteristic (HEMC) method for the assessment of (i) land-use type (CT vs. NT) in soils (30 samples) varying in texture, and (ii) the effect of six PAM concentrations (0, 10, 25, 50, 100, and 200 mg L−1) on three typical soils (sandy clay loam, clay loam, and clay) under CT management; then, the contributions of PAM concentration (CT) and NT were compared. Water retention curves of samples were obtained at a matric potential from 0 to −5.0 J kg−1 and characterized by a modified van Genuchten model that yields (i) model parameters α and n, and (ii) a soil structure stability index (SI). The treatments affected the shape of the water retention curves. Change of land use from CT to NT and PAM application to CT soil increased the SI and ɑ, and decreased n compared to CT-managed soils. The magnitude of the NT and PAM effect was inversely related to soil clay content. CT-managed soils treated with a low PAM rate (10–25 mg L−1) gave SI comparable to that obtained for the NT-managed soils, while CT-managed soils treated with a high PAM rate (50–200 mg L−1) yielded 1.3–2.0 and 2–4 times higher SI than that for NT and CT-managed soils, respectively. Our findings suggest that both the change of land use to NT or the addition of small amounts of PAM are viable alternatives for stabilizing CT-managed weakly alkaline semi-arid soils, whose soil structure stability is a priori limited. Full article
(This article belongs to the Special Issue Soil Structural Degradation Evaluation in Sustainable Agroecosystems)
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19 pages, 1467 KiB  
Article
Parameters of Drainage Waters Collected during Soilless Tomato Cultivation in Mineral and Organic Substrates
by Jacek Dyśko, Magdalena Szczech, Stanisław Kaniszewski and Waldemar Kowalczyk
Agronomy 2020, 10(12), 2009; https://doi.org/10.3390/agronomy10122009 - 20 Dec 2020
Cited by 7 | Viewed by 2968
Abstract
The aim was to determine the suitability of various substrates for application in a closed system of soilless tomato cultivation, based on the potential fitness of drainage waters from these substrates for recirculation. Four substrates were used: rockwool, coir substrate, lignite substrate (Carbomat) [...] Read more.
The aim was to determine the suitability of various substrates for application in a closed system of soilless tomato cultivation, based on the potential fitness of drainage waters from these substrates for recirculation. Four substrates were used: rockwool, coir substrate, lignite substrate (Carbomat) and biodegradable organic substrate (Biopot). Tomato plants grown in these substrates were fertilized with the same amount of nutrient solution, containing the same concentration of nutrients. The characteristics of drainage water from these substrates were analyzed during cultivation. The highest amount of drainage water was collected from the lignite substrate Carbomat. However, these leachates showed good properties for further recirculation: low electro conductivity and turbidity, high nutrient content, moderate microbial load with high population of Trichoderma fungi, and being beneficial for plant growth. Moreover, Carbomat produced the highest tomato yield compared to other substrates. This indicates that this organic substrate is an efficient alternative to rockwool and its drainage water may be reused in a recirculation system. On the contrary, the drainage water from the Biopot substrate showed the worst qualities: high pH and low EC, low concentration of nitrate nitrogen and phosphorus, very high turbidity and a high number of microorganisms. These parameters do not qualify Biopot drainage waters for reuse. Full article
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16 pages, 776 KiB  
Article
Dissecting the Contribution of Environmental Influences, Plant Phenology, and Disease Resistance to Improving Genomic Predictions for Fusarium Head Blight Resistance in Wheat
by Jose Moreno-Amores, Sebastian Michel, Franziska Löschenberger and Hermann Buerstmayr
Agronomy 2020, 10(12), 2008; https://doi.org/10.3390/agronomy10122008 - 20 Dec 2020
Cited by 9 | Viewed by 2286
Abstract
Environmental factors like temperature and humidity are presumed to greatly influence Fusarium head blight FHB infections in wheat. Anther retention AR, on the other hand, is a morphologically neutral trait that shares a common genetic basis with FHB resistance. In this study, our [...] Read more.
Environmental factors like temperature and humidity are presumed to greatly influence Fusarium head blight FHB infections in wheat. Anther retention AR, on the other hand, is a morphologically neutral trait that shares a common genetic basis with FHB resistance. In this study, our aims were to: (i) Evaluate two types of corrections of FHB severity scores, namely method-1 via linear regression on flowering time (FT), and method-2 via a best-subset multiple linear regression analysis comprising FT plus accumulated thermal time variables; and (ii) assess the performance of multi-trait genomic selection (MT.GS) models for FHB severity assisted by AR. The forward prediction scenarios where GS models were trained with data from the previous years revealed average prediction accuracies (PA) of 0.28, 0.33, and 0.36 for FHB severity scores that were uncorrected or corrected by method-1 and method-2, respectively. FHB severity scores free from the influences of both environment and phenology seemed to be the most efficient trait to be predicted across different seasons. Average PA increments up to 1.9-fold were furthermore obtained for the MT.GS models, evidencing the feasibility of using AR as an assisting trait to improve the genomic selection of FHB resistance breeding lines. Full article
(This article belongs to the Special Issue Breeding Healthy Cereals: Genetic Improvement of Fusarium Resistance)
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17 pages, 6010 KiB  
Article
Far Red and Red as Factors Forming Physiological Processes in Spring Barley under Controlled Conditions
by Andrzej Doroszewski, Teresa Doroszewska and Anna Podleśna
Agronomy 2020, 10(12), 2007; https://doi.org/10.3390/agronomy10122007 - 20 Dec 2020
Cited by 2 | Viewed by 1758
Abstract
Solar radiation is a very important energy source for life on Earth and especially for the proper growth and development of plants. Its spectral composition is necessary for a main physiological process in a plant’s life—photosynthesis. In practical agriculture, plants are cultivated in [...] Read more.
Solar radiation is a very important energy source for life on Earth and especially for the proper growth and development of plants. Its spectral composition is necessary for a main physiological process in a plant’s life—photosynthesis. In practical agriculture, plants are cultivated in the stand, which causes neighboring plants not only to compete for water and nutrients but also for light. Living in such an environment, plants have developed different mechanisms for dealing with shading. An aim of the studies conducted here was to determine the effect of the red (R) and far red (FR) range of spectral composition on gas exchange and the other physiological features of spring barley plants. The experiment was conducted in two growth chambers with different spectral compositions of radiation. Spring barley was grown in Mitscherlich pots. The physiological features measured during the two barley developmental phases, i.e., seventh and flag leaves, differed depending on the R/FR ratio used in these chambers. Plants that grew under conditions of a high R/FR ratio showed a higher photosynthesis efficiency, intracellular CO2 concentration, stomatal conductance and transpiration of water but lower values of the water use efficiency (WUE) index. The leaves of plants treated with this kind of light (higher R/FR ratio) had a greater stomata number and higher content of chlorophyll when compared to plants grown under conditions with a low R/FR ratio. Full article
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12 pages, 3553 KiB  
Article
A New Diversity Panel for Winter Rapeseed (Brassica napus L.) Genome-Wide Association Studies
by David P. Horvath, Michael Stamm, Zahirul I. Talukder, Jason Fiedler, Aidan P. Horvath, Gregor A. Horvath, Wun S. Chao and James V. Anderson
Agronomy 2020, 10(12), 2006; https://doi.org/10.3390/agronomy10122006 - 20 Dec 2020
Cited by 5 | Viewed by 2554
Abstract
A diverse population (429 member) of canola (Brassica napus L.) consisting primarily of winter biotypes was assembled and used in genome-wide association studies. Genotype by sequencing analysis of the population identified and mapped 290,972 high-quality markers ranging from 18.5 to 82.4% missing markers [...] Read more.
A diverse population (429 member) of canola (Brassica napus L.) consisting primarily of winter biotypes was assembled and used in genome-wide association studies. Genotype by sequencing analysis of the population identified and mapped 290,972 high-quality markers ranging from 18.5 to 82.4% missing markers per line and an average of 36.8%. After interpolation, 251,575 high-quality markers remained. After filtering for markers with low minor allele counts (count > 5), we were left with 190,375 markers. The average distance between these markers is 4463 bases with a median of 69 and a range from 1 to 281,248 bases. The heterozygosity among the imputed population ranges from 0.9 to 11.0% with an average of 5.4%. The filtered and imputed dataset was used to determine population structure and kinship, which indicated that the population had minimal structure with the best K value of 2–3. These results also indicated that the majority of the population has substantial sequence from a single population with sub-clusters of, and admixtures with, a very small number of other populations. Analysis of chromosomal linkage disequilibrium decay ranged from ~7 Kb for chromosome A01 to ~68 Kb for chromosome C01. Local linkage decay rates determined for all 500 kb windows with a 10kb sliding step indicated a wide range of linkage disequilibrium decay rates, indicating numerous crossover hotspots within this population, and provide a resource for determining the likely limits of linkage disequilibrium from any given marker in which to identify candidate genes. This population and the resources provided here should serve as helpful tools for investigating genetics in winter canola. Full article
(This article belongs to the Section Crop Breeding and Genetics)
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22 pages, 8457 KiB  
Article
Application of Multi-Component Conditioner with Clinoptilolite and Ascophyllum nodosum Extract for Improving Soil Properties and Zea mays L. Growth and Yield
by Jacek Długosz, Anna Piotrowska-Długosz, Karol Kotwica and Ewelina Przybyszewska
Agronomy 2020, 10(12), 2005; https://doi.org/10.3390/agronomy10122005 - 20 Dec 2020
Cited by 9 | Viewed by 2088
Abstract
The application of various conditioners in agriculture is one of the management practices used to improve soil quality and plant growth and development. The aim of this study was to assess the effect of a multi-component conditioner on the selected soil properties and [...] Read more.
The application of various conditioners in agriculture is one of the management practices used to improve soil quality and plant growth and development. The aim of this study was to assess the effect of a multi-component conditioner on the selected soil properties and maize (Zea mays L.) growth and yield. The effect of a conditioner on a set of soil properties and maize growth and yield was studied in one-year experiments carried out at three study sites, which were under a conventional tillage system. All of the study sites were located on farms in three geographic mezoregions in the Kuyavian-Pomeranian Region (Midwestern Poland). The studied soils were Haplic Luvisol (Janocin and Kobylnica) and Albic Luvisols (Krukówko) that were composed of sandy loam. A one-way analysis of variance (ANOVA) was used to determine the effect of a conditioner Solactiv on the soil and plant properties. The conditioner significantly affected the soil enzyme activities such as dehydrogenase (DHA), fluorescein sodium salt hydrolysis level (FDAH) and carboxymethylcellulose cellulase (CMC—cellulase); wherein the last one increased by about 16–20%. The application of Solactiv also increased the available K content (about 11%) but not the content of the microbial biomass C and N. Total porosity (TP), which was significantly higher in the soil treated with conditioner than in the control soils, increased the available water capacity (AWC) (about 2.2%). The higher AWC in the treated soil indicated the greater contribution of the mesopores in the TP (about 4%). A significantly higher readily available water capacity (RAWC) and small pores available water capacity (SAWC) was determined in the treated soils compared to the controls. Of the plant properties, only plant height, fresh cob biomass (BBCH 87–89) and fresh plant biomass (BBCH 84–85) were significantly increased by the conditioner. The application of Solactiv is considered to be a promising approach for developing sustainable agriculture by improving the soil’s biological activity and water-related properties. Full article
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12 pages, 1319 KiB  
Article
Differential Influence of No-Tillage and Precipitation Pulses on Soil Heterotrophic and Autotrophic Respiration of Summer Maize in the North China Plain
by Kun Du, Fadong Li, Peifang Leng, Zhao Li, Chao Tian, Yunfeng Qiao and Zhaoxin Li
Agronomy 2020, 10(12), 2004; https://doi.org/10.3390/agronomy10122004 - 20 Dec 2020
Cited by 14 | Viewed by 1996
Abstract
It is important to strengthen the studies on the response of soil respiration components to tillage practices and natural precipitation in cropland. Therefore, soil heterotrophic respiration (RH) and autotrophic (RA) respiration were monitored by a root exclusion method in [...] Read more.
It is important to strengthen the studies on the response of soil respiration components to tillage practices and natural precipitation in cropland. Therefore, soil heterotrophic respiration (RH) and autotrophic (RA) respiration were monitored by a root exclusion method in the North China Plain (NCP). The tillage practices included no-tillage (NT) and conventional tillage (CT), and the study periods were the summer maize growth stages in 2018 and 2019. RH, RA, soil water content and temperature were measured continuously for 113 days by an automatic sampling and analysis system. The soil RH values on bright days and rain-affected days were higher under NT in 2018 (14.22 and 15.06 g CO2 m−2 d−1, respectively) than in 2019 (8.25 and 13.30 g CO2 m−2 d−1, respectively). However, the RA values on bright days and rain-affected days were lower under NT in 2018 (4.74 and 4.97 g CO2 m−2 d−1, respectively) than in 2019 (5.67 and 6.93 g CO2 m−2 d−1, respectively). Moreover, NT decreased RH but increased RA compared to CT in 2019. Compared to bright days, the largest increase in both RH and RA after rain pulses was under CT in 2019 (6.75 and 1.80 g CO2 m−2 d−1, respectively). Soil water content and soil temperature were higher in 2018 than in 2019. Moreover, NT increased soil water content and decreased soil temperature on bright days compared to CT in 2019. Furthermore, soil temperature accounted for more variations in RH on bright days and rain-affected days, but soil water content had a greater influence on RA on bright days. However, after precipitation, higher soil water content decreased RA under NT in 2018, while soil water content was positively related to RA under CT in 2019. This study determined the differential response of RH and RA to tillage practices and natural precipitation pulses, and we confirmed that excessively dry soil increases soil carbon loss after rain events in the NCP. Full article
(This article belongs to the Section Water Use and Irrigation)
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20 pages, 1177 KiB  
Article
The Effect of Climate Change on Linolenic Fatty Acid in Oilseed Rape
by Marek Wójtowicz and Andrzej Wójtowicz
Agronomy 2020, 10(12), 2003; https://doi.org/10.3390/agronomy10122003 - 20 Dec 2020
Cited by 10 | Viewed by 2023
Abstract
Linolenic acid content plays a significant role in the quality of oilseed rape oil. With the use of a model developed to calculate linolenic acid content depending on temperature, we performed simulations focused on the predicted changes of linolenic acid content triggered by [...] Read more.
Linolenic acid content plays a significant role in the quality of oilseed rape oil. With the use of a model developed to calculate linolenic acid content depending on temperature, we performed simulations focused on the predicted changes of linolenic acid content triggered by expected climate change. The aim of the study was realized with the use of meteorological data recorded at 16 locations, representing 16 provinces in Poland, in the period of 1986–2005, and values obtained after the transformation of the recorded data to reflect temperature changes in four different representative concentration pathway scenarios (RCP2.6, RCP4.5, RCP6.0, RCP8.5) according to the gfdl_esm2m climate model. The results of the simulations performed under all tested scenarios (RCP2.6, RCP4.5, RCP6.0, RCP8.5) for all analyzed periods (2020–2039, 2040–2059, 2060–2079, 2080–2099) indicate a reduction of linolenic acid content as an effect of climate change. The comparison of simulation results obtained with and without allowing for the influence of temperature on oilseed rape development revealed the dominant role of direct influence in modifying the linolenic acid content. An analysis of the results also indicated how indirect influence of climate change, as expressed in changes of linolenic acid content generated by the acceleration of oilseed rape maturation, reduces the direct influence of climate change, expressed in changes of linolenic acid content caused by temperature. Additionally, simulation results point to opportunities, triggered by climate change, for a diversity of regions in terms of linolenic acid content in comparison to the years of 1986–2005. Full article
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13 pages, 1302 KiB  
Article
Estimating Soybean Radiation Use Efficiency Using a UAV in Iowa
by Xavier A. Phillips, Yuba R. Kandel, Mark A. Licht and Daren S. Mueller
Agronomy 2020, 10(12), 2002; https://doi.org/10.3390/agronomy10122002 - 20 Dec 2020
Cited by 3 | Viewed by 2440
Abstract
Radiation use efficiency (RUE) is difficult to estimate and unreasonable to perform on a small plot scale using traditional techniques. However, the increased availability of Unmanned Aerial Vehicles (UAVs) provides the ability to collect spatial and temporal data at high resolution and frequency, [...] Read more.
Radiation use efficiency (RUE) is difficult to estimate and unreasonable to perform on a small plot scale using traditional techniques. However, the increased availability of Unmanned Aerial Vehicles (UAVs) provides the ability to collect spatial and temporal data at high resolution and frequency, which has made a potential workaround. An experiment was completed in Iowa to (i) demonstrate RUE estimation of soybean [Glycine max (L.) Merr.] from reflectance data derived from consumer-grade UAV imagery and (ii) investigate the impact of foliar fungicides on RUE in Iowa. Some fungicides are promoted to have plant health benefits beyond disease protection, and changes in RUE may capture their effect. Frogeye leaf spot severity did not exceed 2%. RUE values ranged from 0.98 to 1.07 and 0.96 to 1.12 across the entire season and the period post-fungicide application, respectively, and fell within the range of previously published soybean RUE values. Plots treated with fluxapyroxad + pyraclostrobin had more canopy cover (p = 0.078) compared to the non-treated control 133 days after planting (DAP), but yields did not differ. A “greening effect” was detected at the end of the sample collection. RUE estimation using UAV imagery can be considered a viable option for the evaluation of management techniques on a small plot scale. Since it is directly related to yield, RUE could be an appropriate parameter to elucidate the impact of plant diseases and other stresses on yield. Full article
(This article belongs to the Special Issue Remote Sensing in Agriculture)
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12 pages, 1806 KiB  
Article
Solar Drying of Greenhouse Crop Residues for Energy Valorization: Modeling and Determination of Optimal Conditions
by Maria Guadalupe Pinna-Hernández, Francisco Gabriel Acien Fernández, José Gabriel López Segura and José Luis Casas López
Agronomy 2020, 10(12), 2001; https://doi.org/10.3390/agronomy10122001 - 19 Dec 2020
Cited by 6 | Viewed by 2201
Abstract
Large amounts of crop residue are produced annually in areas such as Almeria (Spain). These residues have elevated moisture and ash contents, and are also very heterogeneous, which hinders their reutilization. With the aim of facilitating biomass utilization in energy recovery-related processes, a [...] Read more.
Large amounts of crop residue are produced annually in areas such as Almeria (Spain). These residues have elevated moisture and ash contents, and are also very heterogeneous, which hinders their reutilization. With the aim of facilitating biomass utilization in energy recovery-related processes, a model for solar drying was developed. Experiments were performed inside a greenhouse with tomato and pepper residues, following two strategies (hung or stacked residues). The influence of temperature and relative humidity on the residues’ equilibrium moisture was also studied. The results were that a model allowed for determination of the equilibrium moisture as a function of ambient conditions (temperature and relative humidity), with the model’s characteristic parameters being different for each crop residue. Regarding the drying process, the results conform to first-order kinetics, with the values of the kinetic constants varying as a function of the crop residues and their arrangement. The variation in equilibrium moisture as a function of the annual variation in ambient conditions (temperature and relative humidity) in Almería means that it would only be possible to dry crop residues inside greenhouse below a moisture level of 0.43 kgwater/kgdrysolids (30% water content) from April to November. Full article
(This article belongs to the Special Issue Characteristics and Technology in Mediterranean Agriculture)
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21 pages, 3296 KiB  
Article
Soil Monitoring Methods to Assess Immediately Available Soil N for Fertigated Sweet Pepper
by Alejandra Rodríguez, M. Teresa Peña-Fleitas, Francisco M. Padilla, Marisa Gallardo and Rodney B. Thompson
Agronomy 2020, 10(12), 2000; https://doi.org/10.3390/agronomy10122000 - 19 Dec 2020
Cited by 10 | Viewed by 2111
Abstract
Excessive N application occurs in greenhouse vegetable production. Monitoring methods of immediately available soil N are required. [NO3] in soil solution, sampled with ceramic cup samplers, and [NO3] in the 1:2 soil to water (v/ [...] Read more.
Excessive N application occurs in greenhouse vegetable production. Monitoring methods of immediately available soil N are required. [NO3] in soil solution, sampled with ceramic cup samplers, and [NO3] in the 1:2 soil to water (v/v) extract were evaluated. Five increasing [N], from very N deficient (N1) to very N excessive (N5) were applied throughout three fertigated pepper crops by combined fertigation/drip irrigation. The crops were grown in soil in a greenhouse. Soil solution [NO3] was measured every 1–2 weeks, and extract [NO3] every 4 weeks. Generally, for treatments N1 and N2, both soil solution and extract [NO3] were continually close to zero, and increased with applied [N] for treatments N3–5. The relationships of both methods to the nitrogen nutrition index (NNI), an indicator of crop N status, were assessed. Segmented linear analysis gave R2 values of 0.68–0.70 for combined data from entire crops, for both methods. NNI was strongly related to increasing [NO3] up to 3.1 and 0.9 mmol L−1 in soil solution and extracts, respectively. Thereafter, NNI was constant at 1.04–1.05, with increasing [NO3]. Suggested sufficiency ranges were derived. Soil solution [NO3] is effective to monitor immediately available soil N for sweet pepper crops in SE Spain. The extract method is promising. Full article
(This article belongs to the Special Issue Management of Crops Fertigation)
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19 pages, 4540 KiB  
Article
Photosynthetic and Agronomic Traits of Winter Barley (Hordeum vulgare L.) Varieties
by József Csajbók, Péter Pepó and Erika Kutasy
Agronomy 2020, 10(12), 1999; https://doi.org/10.3390/agronomy10121999 - 19 Dec 2020
Cited by 6 | Viewed by 2341
Abstract
We tested six winter barley (Hordeum vulgare L.) cultivars in a small plot field experiment, measuring photosynthesis and other parameters three times during the growing season. Four genotypes—Andoria, Jakubus, Paradies and Zophia—are new, promising varieties with requirements of intensive technology, high yield [...] Read more.
We tested six winter barley (Hordeum vulgare L.) cultivars in a small plot field experiment, measuring photosynthesis and other parameters three times during the growing season. Four genotypes—Andoria, Jakubus, Paradies and Zophia—are new, promising varieties with requirements of intensive technology, high yield potential and very good disease resistance. The two popular Hungarian varieties (KG Apavár and KG Puszta) are relatively old but they have good tolerance to extreme ecological conditions and outstanding resistance and winter hardiness. The aim of our research was to test the new varieties’ performance. Several recent studies found close connections among various photosynthetic parameters in barley, and we confirmed that in our research. There were significant differences between the varieties in the assimilation rate—the highest values were measured at the BBCH 47–49 stage (end of booting), except Jakubus and Zophia, where the highest values were at BBCH 73–75 (milk ripe). The cultivars’ response to irradiation change varied, especially at higher photosynthetic photon flux density (PPFD) levels. In April and May, the plants were in drought stress according to the intercellular CO2 level and the total conductance to carbon dioxide. The differences between the air and leaf temperature were also low, indicating water stress, but the assimilation rate was relatively high (9.07–14.09 µmol m−2 s−1).We found a close connection between normalized difference vegetation index (NDVI) values and grain protein content in each of the tested barley cultivars. The correlation was significant, at p = 0.01 level. The protein yield per hectare was determined rather by grain yield than protein content. The relationship between the NDVI values and grain yield was moderate, but NDVI values and protein content are in strong correlation. Full article
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18 pages, 2068 KiB  
Article
Genotype-by-Environment Interaction Effects under Heat Stress in Tropical Maize
by Vinayan Madhumal Thayil, Pervez H. Zaidi, Kaliyamoorthy Seetharam, Reshmi Rani Das, Sudarsanam Viswanadh, Salahuddin Ahmed, Mohammad Alamgir Miah, Kesab B. Koirala, Mahendra Prasad Tripathi, Mohammad Arshad, Kamal Pandey, Ramesh Chaurasia, Prakash H. Kuchanur, Ayyanagouda Patil and Shyam S. Mandal
Agronomy 2020, 10(12), 1998; https://doi.org/10.3390/agronomy10121998 - 19 Dec 2020
Cited by 10 | Viewed by 2688
Abstract
Spring maize area has emerged as a niche market in South Asia. Production of maize during this post-rainy season is often challenged due to heat stress. Therefore, incorporating heat stress resilience is an important trait for incorporation in maize hybrids selected for deployment [...] Read more.
Spring maize area has emerged as a niche market in South Asia. Production of maize during this post-rainy season is often challenged due to heat stress. Therefore, incorporating heat stress resilience is an important trait for incorporation in maize hybrids selected for deployment in this season. However, due to the significant genotype × environment interaction (GEI) effects under heat stress, the major challenge lies in identifying maize genotypes with improved stable performance across locations and years. In the present study, we attempted to identify the key weather variables responsible for significant GEI effects, and identify maize hybrids with stable performance under heat stress across locations/years. The study details the evaluation of a set of prereleased advanced maize hybrids across heat stress vulnerable locations in South Asia during the spring seasons of 2015, 2016 and 2017. Using factorial regression, we identified that relative humidity (RH) and vapor pressure deficit (VPD) as the two most important environmental covariates contributing to the large GEI observed on grain yield under heat stress. The study also identified reproductive stage, starting from tassel emergence to early grain-filling stage, as the most critical crop stage highly susceptible to heat stress. Across-site/year evaluation resulted in identification of six high yielding heat stress resilient hybrids. Full article
(This article belongs to the Special Issue Drought and Heat Stress Regulation on Crop Development and Yield)
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25 pages, 4068 KiB  
Article
Water Saving and Yield of Potatoes under Partial Root-Zone Drying Drip Irrigation Technique: Field and Modelling Study Using SALTMED Model in Saudi Arabia
by Abdulrasoul Al-Omran, Ibrahim Louki, Arafat Alkhasha, Mohamed Hassan Abd El-Wahed and Abdullah Obadi
Agronomy 2020, 10(12), 1997; https://doi.org/10.3390/agronomy10121997 - 19 Dec 2020
Cited by 8 | Viewed by 2463
Abstract
This study aims to evaluate the Partial Root Zone Drying Irrigation System (PRD) as one of the modern technologies that provide irrigation water and increase the efficiency of its use on potato crop. The effect of applying the PRD conventional deficit irrigation (CDI) [...] Read more.
This study aims to evaluate the Partial Root Zone Drying Irrigation System (PRD) as one of the modern technologies that provide irrigation water and increase the efficiency of its use on potato crop. The effect of applying the PRD conventional deficit irrigation (CDI) on the efficiency and water saving in potato crops using the drip surface (S) and subsurface (SS) irrigation methods were investigated. SALTMED model used to predict soil moisture and salinity distribution, soil nitrogen dynamics, and yield of potato crop using the different irrigation levels (150%, 100%, and 50% of Crop evapotranspiration (ETc)). The study showed that the water use efficiency (WUE) decreases with increasing levels of irrigation water, as it ranged between 2.96 and 8.38 kgm−3, 2.77 and 7.01 kgm−3 for surface irrigation PRD and CDI, respectively, when the amounts of irrigation water varied from 308 mm to 1174 mm, respectively. The study showed that the irrigation efficiencies were the highest when using PRD system in all treatments when irrigating the potato crop during the spring season, and it was more efficient in the case of using subsurface irrigation method. The results show that the soil moisture (SM) was high in 25–45 cm at 150% of ETc was 0.166 and 0.263 m3m−3 for the first and last stages of growth, respectively. 100% of ETc, (SM) was 0.296 m3m−3 at 0–25 cm, 0.195 m3m−3 at 25–45 cm, 0.179 m3m−3 at 45–62 cm, depths, respectively. whereas 50% of ETc, (SM) was 0.162 m3m−3 at 0–25 cm, 0.195 m3m−3 at 25–85 cm, depths. At 100% of ETc, soil salinity was 5.15, 4.37, 3.3, and 4.5 dSm−1, whereas at 50%, ETc, these values were 5.64, 9.6, 3.3, and 4.2 dSm−1. Statistical indicators showed that the model underestimated yield, for 150%, 100%, and 50% of ETc. Therefore, it can be concluded that yield and WUE using PRD systems were the highest in the potato crop compare to CDI surface and sub-surface, and SALTMED model can predict the moisture distribution, salinity, and yield of potatoes after accurate adjustment. Full article
(This article belongs to the Special Issue Water Saving in Irrigated Agriculture)
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18 pages, 7237 KiB  
Article
Geostatistical Analysis of Soil C/N Deficiency and Its Effect on Agricultural Land Management of Major Crops in Eastern Croatia
by Mladen Jurišić, Dorijan Radočaj, Stjepan Krčmar, Ivan Plaščak and Mateo Gašparović
Agronomy 2020, 10(12), 1996; https://doi.org/10.3390/agronomy10121996 - 18 Dec 2020
Cited by 12 | Viewed by 2513
Abstract
Interpolation accuracy of the soil carbon-to-nitrogen ratio (C/N) has a direct impact on soil maps for agricultural land management planning, affecting the financial gains of farmers and environmental contamination. This study aimed to evaluate the effect of different ordinary kriging parameters on the [...] Read more.
Interpolation accuracy of the soil carbon-to-nitrogen ratio (C/N) has a direct impact on soil maps for agricultural land management planning, affecting the financial gains of farmers and environmental contamination. This study aimed to evaluate the effect of different ordinary kriging parameters on the interpolation accuracy and spatial variability of soil C/N. These values were necessary to determine the effect of potential soil C/N deficiency on five major crops in the study area during 2017–2019, containing maize, wheat, sunflower, rapeseed and soybean parcels. The Gaussian model with logarithmic transformation produced the higher outer accuracy, representing the prediction accuracy. Average values of final soil C/N rasters resulted as 11.35 at 0–10 cm soil depth and 12.60 at 20–30 cm soil depth, representing values 11.0% higher at a deeper soil layer. The moderate soil N deficiency was observed for all major crops, having soil C/N values mainly higher than 12:1, compared to the optimal value range of 9:1 to 12:1. These observations suggest a need for the adjustment of agricultural land management plans through the regionalization of agricultural production to prevent further soil degradation and ensure optimal crop development conditions. Full article
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11 pages, 3021 KiB  
Review
Do We Need New Crops for Arid Regions? A Review of Fruit Species Domestication in Israel
by Yosef Mizrahi
Agronomy 2020, 10(12), 1995; https://doi.org/10.3390/agronomy10121995 - 18 Dec 2020
Cited by 7 | Viewed by 2757
Abstract
Climatic changes have created the imminent need for the development of new crops for arid regions. We started to domesticate and introduce wild and exotic fruit trees to our deserts in 1984. We tested different species in five eco zones in Israel, differing [...] Read more.
Climatic changes have created the imminent need for the development of new crops for arid regions. We started to domesticate and introduce wild and exotic fruit trees to our deserts in 1984. We tested different species in five eco zones in Israel, differing from each other in terms of maximum and minimum temperatures, type and degrees of salinities, water evaporation rates, rainfall, etc. We succeeded in cultivating pitaya species using hybrids from the Hylocereus and Selenicereus genera, and with a different species from the Cactaeae Cereus peruvianus, which we named Koubo. These two species are from the Cactaceae family, known for high water use efficiencies (WUE). We already have investors who started the semi-commercial production of Marula, Sclerocarya birrea sbsp. Caffra, and Argan—Argania spinosa. In spite of the fact that we developed good clones and knowledge of how to grow and ship White Sapote, Casimiroa edulis, and Indian jujube, Ziziphus mauritiana, we failed due to a lack of marketing research and development, which is essential for such a project. We have gene banks of some other new fruit crops waiting for investors to grow and bring them into the domestic and world markets. Full article
(This article belongs to the Special Issue New Crops for Arid Regions)
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15 pages, 4835 KiB  
Article
Comparison of the Effect of Meta-Topolin and Benzyladenine during Daphne mezereum L. Micropropagation
by Karolina Nowakowska and Andrzej Pacholczak
Agronomy 2020, 10(12), 1994; https://doi.org/10.3390/agronomy10121994 - 18 Dec 2020
Cited by 19 | Viewed by 3783
Abstract
Meta-Topolin (mT) is one of the lesser-known and only recently discovered cytokinins that can be used as an alternative to the commonly used benzyladenine (BA). The experiment aimed to compare the effects of BA and mT on the regeneration from explants of Daphne [...] Read more.
Meta-Topolin (mT) is one of the lesser-known and only recently discovered cytokinins that can be used as an alternative to the commonly used benzyladenine (BA). The experiment aimed to compare the effects of BA and mT on the regeneration from explants of Daphne mezereum, on the levels of several chemical components, the catalase activity, and to assess genetic diversity of microcuttings. The Murashige and Skoog medium (MS) and the woody plant medium (WPM) were used, enhanced with auxin and 1 mg·L−1 mT or 1 mg·L−1 BA. The results suggest that mT has a more positive effect on shoot regeneration. It also positively affected the levels of various compounds which are generally taken as indicative of micro cutting conditions. The levels of chlorophyll and carbohydrates were the highest in microcuttings from the WPM with 0.1 mg·L−1 NAA. Total soluble proteins and amino acids were the highest in plants from the MS medium with 1 mg·L−1 mT. Increased levels of hydrogen peroxide and catalase activity were observed on media with 1 mg·L−1 BA. Screening with 30 randomly amplified polymorphic DNAs (RAPD) and 20 inter-simple sequence repeat (ISSR) primers demonstrated a considerable level of genetic variation among regenerating plants. This variation is attributed to the condition of the starting material (seed propagated); there were no indications that the two cytokinins tested contributed to increased somaclonal variation. Full article
(This article belongs to the Section Horticultural and Floricultural Crops)
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17 pages, 1119 KiB  
Article
Using Temporally Resolved Floral Resource Maps to Explain Bumblebee Colony Performance in Agricultural Landscapes
by Philipp W. Eckerter, Lars Albus, Sharumathi Natarajan, Matthias Albrecht, Lolita Ammann, Erika Gobet, Felix Herzog, Willy Tinner and Martin H. Entling
Agronomy 2020, 10(12), 1993; https://doi.org/10.3390/agronomy10121993 - 18 Dec 2020
Cited by 11 | Viewed by 2780
Abstract
Wild bumblebees are key pollinators of crops and wild plants that rely on the continuous availability of floral resources. A better understanding of the spatio-temporal availability and use of floral food resources may help to promote bumblebees and their pollination services in agricultural [...] Read more.
Wild bumblebees are key pollinators of crops and wild plants that rely on the continuous availability of floral resources. A better understanding of the spatio-temporal availability and use of floral food resources may help to promote bumblebees and their pollination services in agricultural landscapes. We placed colonies of Bombus terrestris L. in 24 agricultural landscapes with various degrees of floral resource availability and assessed different parameters of colony growth and fitness. We estimated pollen availability during different periods of colony development based on detailed information of the bumblebee pollen diet and the spatial distribution of the visited plant species. Total pollen availability did not significantly explain colony growth or fitness. However, when using habitat maps, the weight gain of colonies, the number of queen cells, and colony survival decreased with increasing distance from the forest. The better explanation of bumblebee performance by forest proximity than by (plant-inferred) pollen availability indicates that other functions of forests than pollen provision were important. The conservation of forests next to agricultural land might help to sustain high populations of these important wild pollinators and enhance their crop pollination services. Combining different mapping approaches might help to further disentangle complex relationships between B. terrestris and their environment in agricultural landscapes. Full article
(This article belongs to the Special Issue Pollinator Diversity and Pollination in Agricultural Systems)
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16 pages, 3245 KiB  
Article
Development and Application of Image-Based High-Throughput Phenotyping Methodology for Salt Tolerance in Lentils
by Ruwani Dissanayake, Hossein V. Kahrood, Adam M. Dimech, Dianne M. Noy, Garry M. Rosewarne, Kevin F. Smith, Noel O. I. Cogan and Sukhjiwan Kaur
Agronomy 2020, 10(12), 1992; https://doi.org/10.3390/agronomy10121992 - 18 Dec 2020
Cited by 18 | Viewed by 3856
Abstract
Soil salinity is a major abiotic stress in Australian lentil-producing areas. It is therefore imperative to identify genetic variation for salt tolerance in order to develop lentil varieties suitable for saline soils. Conventional screening methods include the manual assessment of stress symptoms, which [...] Read more.
Soil salinity is a major abiotic stress in Australian lentil-producing areas. It is therefore imperative to identify genetic variation for salt tolerance in order to develop lentil varieties suitable for saline soils. Conventional screening methods include the manual assessment of stress symptoms, which can be very laborious, time-consuming, and error-prone. Recent advances in image-based high-throughput phenotyping (HTP) technologies have provided unparalleled opportunities to screen plants for a range of stresses, such as salt toxicity. The current study describes the development and application of an HTP method for salt toxicity screening in lentils. In a pilot study, six lentil genotypes were evaluated to determine the optimal salt level and the growth stage for distinguishing lentil genotypes using red–green–blue (RGB) images on a LemnaTec Scanalyzer 3D phenomics platform. The optimized protocol was then applied to screen 276 accessions that were also assessed earlier in a conventional phenotypic screen. Detailed phenotypic trait assessments, including plant growth and green/non-green color pixels, were made and correlated to the conventional screen (r = 0.55; p < 0.0001). These findings demonstrated the improved efficacy of an image-based phenotyping approach that is high-throughput, efficient, and better suited to modern breeding programs. Full article
(This article belongs to the Special Issue Salinities—Framing Knowledge into Multiple Agricultural Contexts)
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8 pages, 2736 KiB  
Review
Aegilops Species for the Improvement of the Leaf and Stripe Rust Resistance in Cultivated Triticale (×Triticosecale Wittmack)
by Waldemar Ulaszewski and Michał Tomasz Kwiatek
Agronomy 2020, 10(12), 1991; https://doi.org/10.3390/agronomy10121991 - 18 Dec 2020
Cited by 2 | Viewed by 2100
Abstract
Hexaploid triticale (×Triticosecale Wittmack, 2n = 6x = 42 chromosomes, AABBRR) is a cultivated hybrid, which combines wheat (Triticum aestivum L.) and rye (Secale cereale L.) properties. It has a better ability to be grown on poor soils, [...] Read more.
Hexaploid triticale (×Triticosecale Wittmack, 2n = 6x = 42 chromosomes, AABBRR) is a cultivated hybrid, which combines wheat (Triticum aestivum L.) and rye (Secale cereale L.) properties. It has a better ability to be grown on poor soils, compared to wheat. Mainly, triticale is produced for forage feed and bioethanol. Considering the limited diversity of this human-made crop, there is a need to widen its genetic variability, especially to introduce new genes, responsible for agronomic traits, such as resistance to biotic stresses. Leaf rust caused by Puccinia triticina Eriks. and stripe rust caused by Puccinia striiformis Westend are the most destructive foliar diseases of triticale and related cereals. Developing resistant triticale varieties is an important strategy for the control of these diseases. A number of leaf and stripe rust resistance genes have been already introduced into bread wheat from related species using chromosome manipulations. Exploitation of related species conferring desirable loci is the most effective non-GMO way of improving the rust resistance of triticale. The procedure encompasses chromosome doubling of obtained hybrids followed by a number of backcrosses to eliminate unnecessary alien chromatin and to reduce the linkage drag. In this review, we show the recent status of pre-breeding studies, which are focused on transfer of leaf and stripe rust resistance genes from Aegilops species into cultivated triticale using distant crossing and chromosome engineering. Full article
(This article belongs to the Special Issue Analysis of Crop Genetic and Germplasm Diversity)
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