Pod Harvest Research Articles

An effective picking point localization method for multi-posture lotus pods based on three-view depth vision observation

Different lotus pod individuals have different growth postures, and conventional single-view observation makes it difficult to ensure the visibility of the stalk’s picking segment of all lotus pods, thus affecting the efficiency and quality of automatic picking. To solve this problem, this study proposes a picking point localization method for multi-posture lotus pods based on three-view depth vision observation. It includes three steps: first, the RGB-D (red–green–blue–depth) images of lotus pods are collected from three viewing directions based on the designed three-view depth vision observation scheme. Second, instance segmentation on the lotus pods and stalks in the collected images is performed to obtain mask data. Third, the final lotus pod picking point coordinates and picking vector data are obtained using the proposed lotus pod picking information calculation algorithm. The algorithm comprises the two-dimensional image feature point calculation, single-view picking information calculation, and three-view picking information data synthesis. The three-view observation test of lotus pods in a planting environment shows that the proposed three-view observation scheme can meet the picking segment observation needs of lotus pods in any posture. In addition, lotus pod localization tests were conducted based on a specifically designed localization test bench. The proposed localization method achieved a localization success rate of 98.00 % and 90.86 % for single and multiple lotus pods, respectively. The results verify the feasibility of the proposed localization method for calculating the picking information of arbitrary lotus pods, which can provide essential support for the practical development of automatic lotus pod harvesting technology.

Agronomic and morpho‐physiological response of Andean genotypes of common bean to terminal drought

AbstractDrought is a major production constraint of common bean (Phaseolus vulgaris L.) worldwide. The objectives of this study were to (i) assess the agronomic and morpho‐physiological response of Andean genotypes to terminal drought, and (ii) identify Andean genotypes with an ideal combination of agronomic and morpho‐physiological traits for enhanced drought tolerance. Twenty Andean genotypes and seven checks were evaluated for drought tolerance in three field trials conducted in three locations. Agronomic and morpho‐physiological traits including seed yield, seed weight, shoot dry weight, pod number, pod harvest index, harvest index, and carbon isotope discrimination (CID) were measured. Strong positive correlations were observed between seed yield, and partitioning efficiency metrics and CID (r = 0.57***) under drought, which suggested the important role of assimilate partitioning and water use efficiency in the observed drought tolerance. The heritability estimates for pod harvest index (H2 = 0.88) and harvest index (H2 = 0.87) were higher than for seed yield (H2 = 0.43) and other morpho‐physiological traits, thus they can be used to indirectly select for drought tolerance. Based on the relationship between seed yield and CID under drought stress, 12 genotypes were identified as drought tolerant with high water use efficiency. Among these, three were classified as water savers, while nine as water spenders. Genotypes with an ideal combination of superior shoot dry weight, partition efficiency, water use efficiency, and superior seed yield under both drought stress and non‐stress conditions were identified. The identified genotypes can be used for genetic improvement of drought tolerance in the Andean gene pool of common bean.

Optimal timing for fava bean planting, pod harvesting, and termination in Northern California

Fava bean has been cultivated as a grain, vegetable, and cover crop in California for more than a century. Despite a decline in popularity as a grain, many growers are taking a second look to satisfy demands for vegetable fava bean (pod) and to provide plant-derived nitrogen (N) to grow summer cash crops. This paper presents the results of a series of experiments aimed at quantifying fava bean biomass and N at planting date and termination, as well as pod production in response to the harvest scheme. Sowing before the end of October resulted in the highest biomass and N in Northern California. Termination of fava bean cover crops in early April between the flowering and first pod stage increased the forage yield of the following crop (sudangrass), compared to termination at the earlier branching stage, which is typically in late February. We found that delaying vegetable pod harvest until the end of the growing season resulted in low fresh-pod yields. The results provide a starting point for growers interested in incorporating fava bean.

Korelasi antar Karakter Hasil Lima Varietas Tanaman Kacang Panjang (Vigna sinensis) di Lingkungan Organik

This study aims to determine the correlation between the yield characteristics of the yard long bean yield, and the superiority of one of the varieties in an organic environment. This research was conducted at the Integrated Field Laboratory and Seed and Plant Breeding Laboratory, Faculty of Agriculture, University of Lampung in July 2021 – November 2021. This experiment was arranged in a Completely Randomized Design (CRD) with 3 replications and then continued with data analysis in the form of linear analysis, analysis of diversity , and significance test. The observed variables included flowering age, pod color, pod harvesting age, pod length, pod diameter, number of seeds per pod, sugar content, number of productive branches, number of good pods, total number of seeds, and distance between locules. The results showed that the pod length and the number of seeds per pod (r = 0.66). Total pod weight was positively correlated with the number of productive branches (r = 0.83), the number of good pods (r = 0.96), and the total number of pods (r = 0.96). The number of productive branches correlated positively with the number of good pods (r = 0.87) and the total number of pods (r = 0.86). The number of good pods variable has a positive correlation with the total number of pods (r = 0.98). The Cantonese Tavi variety has an advantage in the number of good pods produced in an organic environment. Keywords: Correlation, Organic Environment.

Salicylic acid and antitranspirant polymer mitigate the effects of water stress on the growth and yield of cowpea

Water stress can limit the growth and production of cowpea (Vigna unguiculata (L.) Walp.), necessitating the use of strategies that induce plant tolerance to mitigate its effects on the crop. This includes the application of salicylic acid (SA) and antitranspirant polymer (AP). The objective of this study was to evaluate the effect of SA and AP applications on the growth and production of cowpeas subjected to water stress. The experiment was conducted in field conditions at Sítio Boqueirão, Catolé do Rocha, Paraíba, Brazil. The experimental design used was randomized blocks, comprising 10 treatments with four replications. The evaluated treatments included nine combinations generated according to the Central Composite Design experimental matrix, involving five doses of SA and five doses of AP applied to plants under water stress, along with an additional treatment (without water stress and application of SA and AP). The assessed variables included morphological parameters and yield. The data were subjected to canonical correspondence analysis and confidence ellipses. The application of SA and AP increased growth (summer and spring) and productivity (summer). However, in spring, there was a decrease in productivity and an increase in the number of days until the initiation of pod harvesting in cowpeas under water stress.

Genotypic Variation Studies in Biomass Partitioning Patterns during Post-flowering Stages under the Late Sown Conditions of Chickpea (Cicer arietinum L.) Germplasm

This study conducted during the 2021-2022 year under field conditions investigates the genotypic variation in biomass partitioning among different chickpea genotypes during post-flowering stages, with a specific emphasis on late sown conditions. The main aim of the study was to elucidate the efficiency of resource allocation toward pod production, measured by the pod harvest index. This research enhances understanding of chickpea performance under delayed sowing conditions by examining genotypic variations in key parameters during critical post-flowering stages, specifically pod filling and seed filling. Biomass partitioning in branches and pods varied considerably during both growth stages, with branches playing a crucial role in pod development during pod filling. The transition from pod filling to seed filling stage resulted in increased biomass partitioning in pods, highlighting their importance as storage organs for seed development. Seed yield exhibited significant variability among genotypes, with some surpassing 2000 kg/ha, while pod harvest index ranged from 35.62% to 70.48%, indicating differences in resource allocation efficiency. Regression analysis showed varying degrees of association between biomass partitioning and pod harvest index, with seed yield and pod harvest index, biomass partitioning in pods exhibiting the highest explanatory power during seed filling. By studying the adaptation of plants towards biphasic and allometric allocation patterns during unfavorable conditions can result in developing the resource use efficient climate resilient varieties. These findings contribute to our understanding of crop productivity under varying environmental conditions and inform strategies for optimizing chickpea yield and resilience.

New cultivars of vegetable cowpea (<i>Vigna unguiculata</i> (l.) walp.) developed at VIR

Background. Cowpea is an important legume crop of great nutritional and economic value, ranking fourth in the world among leguminous crops in the area of cultivation. This crop is known to tolerate high temperatures and droughts, so new cowpea cultivars adapted to the local arid conditions of the Lower Volga are of considerable interest.Materials and methods. Mass and individual selection techniques were applied to develop new cultivars from cowpea landraces held in the VIR collection. Selection was carried out at Astrakhan Experiment Station of VIR in 2012–2018, and variety trials took place in 2019–2021.Results. Cvs. ‘Samma Nova’ and ‘Pasta Grin’ were released for vegetable use. The pod yield of ‘Samma Nova’ is 12.18–14.85 t/ha, seed yield is 0.92–1.14 t/ha, protein content is 28.8% in seeds and 27.1% in pods, and its growing season is 57–66 days. The cultivar is bushy, with synchronous pod and seed maturation, suitable for mechanized cultivation. The pod yield of ‘Pasta Grin’ is 24.68–25.84 t/ha, seed yield is 0.82–1.04 t/ha, protein content is 29.1% in pods and 23.6% in seeds. It is a mid-season cultivar, with a rambling stem, intended for growing on a trellis. Both cultivars significantly exceeded the reference (cv. ‘Sibirsky Razmer”) in most of the studied indicators. The breeding work with cowpea accessions showed that pod harvesting at the commercial ripeness stage stimulated plants to develop new pods, which extended the duration of fruiting and increased productivity. The maximum number of pods in all studied cultivars was formed in the first 20 days of the fruiting period.Conclusion. In 2022, according to the results of competitive and local trials, cvs. ‘Samma Nova’ and ‘Pasta Grin’ were included in the State Register for Selection Achievements (National List). The zones of cultivation and seed production for these cultivars are Astrakhan and Volgograd Provinces, Krasnodar and Stavropol Territories, and the Republic of Crimea.

Adaptive Responses of Biofortified Common Bean Lines to Acidic Soil and High Temperatures in the Colombian Amazon Region

One of the strategies to combat micronutrient malnutrition is by developing biofortified common bean lines (Phaseolus vulgaris L.) capable of tolerating different stress conditions. In this study, the adaptive responses of different biofortified bean lines grown under combined stress of acidic soil and high-temperatures were evaluated in the Colombian Amazon. A total of 247 common bean lines from the Mesoamerican gene pool were used to determine the adaptive response in terms of phenological, physiological, and agronomic behavior under combined stress conditions. The lines tested were obtained from different single crosses, double crosses, and backcrosses between different bean materials, of which 146 were obtained from F4 families with high iron (Fe) content in seed and 99 common bean lines from F5 families. Different bean lines had grain yields (GY) higher than 1400 kg ha−1 from the F5 (lines: 859, 805, 865, and 657) and F4 (lines: 2853 and 2796) families. The superior performance of these lines was related to a higher photosynthate partitioning that has allowed an increase in pod formation (pod partitioning index, PPI) from the canopy biomass (CB) and grain filling (pod harvest index, PHI; harvest index, HI), resulting in higher values of GY. Values of GY were correlated with CB (r = 0.36), PPI (r = 0.6), PHI (r = 0.68), and HI (r = 0.8, p < 0.001). This increase in agronomic performance is due to a greater allocation of energy to the photosynthetic machinery (ΦII) and its dissipation in the form of heat (ΦNPQ), with increases in the leaf temperature difference (LTD). Based on the results obtained, six biofortified lines of common bean (lines F5: 859, 805, 865, and 657; lines F4: 2853 and 2796) showed traits of tolerance to combined stress and can serve as progenitors to increase Fe and Zn concentration in the seeds of lines that tolerate the combined stress from acidic soil and high temperature in the Colombian Amazon region.

Influence of Farmyard Manure and NPS Fertilizer on Hot Pepper (Capsicum annuum L.) Growth and Yield Variables at Western Ethiopia

Hot peppers are important vegetable crops widely grown in Ethiopia. Investigation into the economic, nutritive and therapeutic purposes of the pepper plant is extremely limited. Thus, a field trial was piloted to assess the influence of NPS (compound fertilizer containing three important plant nutrients of nitrogen, phosphate, and sulphur with the ratio of 19% N, 38% P2O5, and 7% S) and farmyard manure (FYM) fertilizer on hot pepper at the Dambi Dollo University research field for two consecutive years (2020 and 2021) under rain fed. The finding was systematized in a Randomized Complete Block Design (RCBD) with three repetitions and variety of Marako Fana hot pepper was assessed. NPS fertilizer at four level (0, 100, 200, 300 kg N ha-1) and four FYM levels (0, 2.5, 5, 7.5, 10 t ha-1) were owed to the study area and a total of 20 treatments. The research results revealed that FYM and NPS mineral fertilizer interacts to affect positively (P<0.05) maximum parameters without unmarketable harvest, which was influenced through the single effect of NPS and FYM. The highest marketable pod yield (2.28 t ha-1) and total pod harvest (2.72 t ha-1) was recorded through NPS rates of 100 kg ha-1 applied with 5 t ha-1 of farmyard manure. Consequently, it is likely to determine that hot pepper farmers can use NPS mineral fertilizer rate of 100 kg ha-1 with 5 t ha-1 of FYM that would expand yield of the hot peppers in the study area with similar agro-ecological conditions.

Structure and labor use pattern among cocoa farmers in Ondo State, Nigeria

Human labour is about the only main source of labour available to smallholder farmers in Nigeria. Smallholder farmers contribute over 85% of domestic agricultural output in Nigeria, hence, human labour accounts for the domestic food supply in Nigeria. Therefore, the need to continue supplying food for the ever-growing Nigerian population anchors on human labour productivity. In Nigerian agriculture, hired labour is predominantly used. Human labour plays a very significant role in agricultural development, especially in developing countries where technological development is still very low. In view of the importance of labour in agricultural production, this study was designed to investigate the structure and use pattern of farm labour in the study area. The study was carried out in Ondo state, Nigeria. A multistage sampling technique was used to collect data from 160 farmers. After sorting for missing data, 144 cocoa farmers’ data were used for analysis in this study. Seventy-five percent of the total
 respondents were above 50 years of age and about 25.01% of the total respondents were 50 years and below. The majority (79.17%) of the farmers were men. Also, 75.07% of the respondents had a formal level of education. In the study contract type of labour is majorly used for most activities in cocoa farming while cooperative labour was seldom used. Activities such as land clearing (75.0%), planting (83.32%), weeding (95.83%), application of chemicals (91.67%), removal of mistletoes (87.50%), harvesting of cocoa pods (87.50%), conveyance of cocoa pods to the pod breaking point (95.83%), breaking of cocoa pods (100%) and conveyance of cocoa beans to the point of fermentation (88.33%) were majorly carried out by contract labour. Male labour was mostly utilized for all the activities as indicated by most farmers. Female labour was sparingly utilized for some activities such as land clearing (8.33%), planting (0%), application of chemicals (8.33%), spraying of chemicals (4.17%), removal of mistletoes (0%) and harvesting of cocoa pods (12.5%). The study recommended that funds should be made available to farmers to engage in contract labour and also there should be the need to use equipment and machinery to reduce drudgery.

Evaluation of Rhizobial Inoculation in Comparison to Urea Fertilizer Application of Vegetable Bean (<em>Phaseolus vulgaris</em> L)

A field trial was conducted to evaluate the effects of Rhizobium inoculation in comparison to nitrogen fertilizer (NF) application on vegetable bean in the Ankumbura area, Kandy district during the Maha 2018/19 season. Six treatments were employed comprising four NF levels (55, 110, 165, and 220 kg urea/ha), rhizobium inoculation without NF, and control with neither NF nor inoculant. The treatments were set out in a randomized complete block design with three replicates. Four NF levels were 25%, 50%, 75%, and 100% of the recommended level for vegetable bean by the Department of Agriculture (DOA). All the treatments received potassium and phosphorous according to DOA recommendations. Pod yield/m2, growth parameters, several nodule parameters, and weed biomasses were recorded. Total yield (t/ha) was calculated based on the pod harvest. A yield versus fertilizer response curve was developed using calculated yield data. The highest total yield (3.03t/ha) with the application of 220kg/ha of urea was not significantly different from the yield produced under inoculation without NF (2.93 t/ha). This implies that inoculation facilitates a possible replacement of NF. Number of root nodules (30) and number of leaves (36) were significantly higher with inoculation. Higher levels; of 75% and 100% of recommended NF reduced nodule dry weight. Pod length, diameter, and dry weight with 100% and 75% NF levels were not significantly different (p<0.05) from those with inoculation. The highest pod N-yield (0.0586 g) and shoot N-yield (0.253 g) were recorded with inoculation and 220kg/ha urea application respectively. Weed biomass was significantly reduced (70%) with inoculation compared to the highest NF treatment. The results indicate a potential avenue to decrease the need for chemical nitrogen fertilizer and use inoculation to manage weed growth in vegetable beans in the Ankumbura area.

A comb-brushing-type green soybean pod harvesting equipment: Design and experiment.

To solve the problem of low efficiency of manual harvesting of green soybeans and lack of adaptable harvesters, in this study, a brushing-type green soybean harvester was designed. The comb-brushing type green soybean pod harvesting equipment is composed of a front-mounted separation drum, a full-width material delivery mechanism, a negative pressure cleaning system, and a stalk-pod separation system. Based on the operation requirements of the front-mounted brushing-type detachment drum, the drum parameters, parameters of comb arrangement, and structural parameters of the comb, the force analysis in detachment was performed. By taking the pod detachment rate and damage rate as the response indexes, the rotational speed of the drum, the travel speed of the device, and teeth distance as influencing factors, a three-factor five-level orthogonal rotary combination test was carried out by the software Design-Expert. By establishing mathematical regression models for various influencing factors and evaluation indicators, conducting variance analysis and significance analysis on the response indicators of each factor, the optimal parameters were obtained at a rotational speed of teeth of 397.36 rpm/min, minimum axial teeth distance of 4.8 mm and travel speed of the device of 0.5 m/s. Field test results showed that, under the optimal parameter combination, the pod detachment rate was 94%, the damage rate was 3.04%, the harvesting efficiency was greater than 0.187 hm2/h, and impurity content was less than 7.8%, all of which met the design and usage requirements. The research results can provide a reference for the design of soybean harvesters.

Phenotypic Variation of Component Traits Affecting Maturity in Cultivated Peanut (Arachis hypogaea L.)

A wide range of time-to-maturity exists among peanut accessions and cultivars, and it is a complex trait likely controlled by many genes and influenced by the environment. Underground formation of fruit coupled with indeterminate growth habit makes peanut a difficult crop species to explore genetic controls of this trait. Dividing the total phenotype of time-to-maturity into component traits can facilitate the dissection of genetic pathways controlling maturity in peanut. In this study, component traits contributing to time-to-maturity included flowering on the main stem, flowering rate, flower-to-peg conversion ratio, internode length, distribution of reproductive and vegetative nodes, branch numbers, percentage of harvestable pods, and harvest index, which were quantified for six genetically diverse peanut genotypes. Statistically significant differences were detected for all measured traits among the tested genotypes. These genotypes are parental lines of four established recombinant inbred populations. Populations with contrasting parental phenotypic values could be utilized for further QTL mapping of the relevant traits.

Instance Segmentation of Lotus Pods and Stalks in Unstructured Planting Environment Based on Improved YOLOv5

Accurate segmentation of lotus pods and stalks with pose variability is a prerequisite for realizing the robotic harvesting of lotus pods. However, the complex growth environment of lotus pods causes great difficulties in conducting the above task. In this study, an instance segmentation model, LPSS-YOLOv5, for lotus pods and stalks based on the latest YOLOv5 v7.0 instance segmentation model was proposed. The CBAM attention mechanism was integrated into the network to improve the model’s feature extraction ability. The scale distribution of the multi-scale feature layer was adjusted, a 160 × 160 small-scale detection layer was added, and the original 20 × 20 large-scale detection layer was removed, which improved the model’s segmentation accuracy for small-scale lotus stalks and reduced the model size. On the medium-large scale test set, LPSS-YOLOv5 achieved a mask mAP0.5 of 99.3% for all classes. On the small-scale test set, the mAP0.5 for all classes and AP0.5 for stalks were 88.8% and 83.3%, which were 2.6% and 5.0% higher than the baseline, respectively. Compared with the mainstream Mask R-CNN and YOLACT models, LPSS-YOLOv5 showed a much higher segmentation accuracy, speed, and smaller size. The 2D and 3D localization tests verified that LPSS-YOLOv5 could effectively support the picking point localization and the pod–stalk affiliation confirmation.

Efficacy Evaluation of Organic Fertilizers on Growth, Yield and Quality Parameters of French Beans, Maize and Kale in Different Counties of Kenya

Sustainable agriculture is an important global issue. Organic fertilizer application improves crop growth by supplying plant nutrients, including micronutrients, as well as improving the physical, chemical, and biological properties of the soil, thereby providing a better environment for root development by improving the soil structure. It has been widely reported that continuous applications of inorganic fertilizers alone resulted in deterioration of soil health in terms of physical, chemical, and biological properties of the soil. Understanding the nutrient variability and release pattern of organic fertilizers is crucial to supply plants with sufficient nutrients to achieve optimum productivity, while also rebuilding soil fertility and ensuring protection of environmental and natural resources. This study was conducted to determine the efficacy of Fertiplus on growth, quality and yield in Kale, Maize and French Beans in Kenya. The trial plots were 3 m×3 m arranged in a randomized complete block design and replicated 4 times. The treatments consisted Fertiplus 4-3-3 alone; Fertiplus 4-3-3+100% recommended fertilizer practice; Fertiplus 4-3-3+50% recommended fertilizer practice; Fertiplus 4-3-3+75% recommended fertilizer practice; Reference product (Permeate); recommended fertilizer practice (Conventional) and the absolute control. Application of Fertiplus plus 50% of the recommended fertilizer practice led to the highest number of pods per plant (18) and application with 75% of the recommended fertilizer practice showed a peak harvest of fresh pods with 374.3 g per plant. In an area of 1 m2, application of Fertiplus and 50% recommended fertilizer practice had 6.7 kilograms of kale with a maximum of 14 mature leave per plant in a span of 20 days. In maize, the Fertiplus and 50% recommended fertilizer treatment showed the highest cob weight per plant (480 g) and an average grain yield of 396.7 g per plant compared to the doubled level (100%) of the recommended fertilizer practice that had 401 g per plant. From the study, it was observed that the highest yield of the three study crops were under the integrated treatments of the organic fertilizer and half the rate of synthetic fertilizer program.

Potential of Faba Bean (Vicia faba L.) for Dual-purpose Vegetable Production and Cover Cropping

Cover cropping has been strongly promoted, but few growers have realized the benefits of this practice due to challenges linked to economic returns and whole-system management. In the western United States, winter legumes including faba bean have the potential to add economic value while offering soil health benefits compared with fallow fields. This experiment assessed the potential of five vegetable faba bean varieties for fresh pod yield, fresh pod quality, and biomass N return under a single and multiple pod harvest scheme. Vegetable faba bean varieties were further compared with two popular cover crop faba bean varieties, ‘Bell bean’ and ‘Sweet Lorane’ for cover crop and biomass N return benefits. The experiment revealed significant (P ≤ 0.05) genotypic variation for vegetable fresh pod yield, dry biomass, fresh pod quality, pod N removal, biomass N return, and C:N in three testing environments under the single and multiple harvest schemes. Finally, the vegetable variety ‘Vroma’ produced high average fresh pod yield under the single (16,178 kg·ha−1) and multiple (38,928 kg·ha−1) harvest schemes while maintaining high biomass N return under the single (119 kg·ha−1 N) and multiple harvests (97 kg·ha−1 N) compared with the cover crop varieties (128 kg·ha−1 N). This experiment demonstrated that a single fresh pod harvest on an early and high yielding faba bean variety can generate economic returns while also providing cover crop benefits that are comparable to termination of a faba bean cover crop on the same date.

Adoption of Post-Harvest Strategies to Minimize Aflatoxin Contamination in Groundnut (Arachis Hypogaea) in Ghana

Aflatoxin, a mycotoxin caused by the mold Aspergillus flavus or parasiticus, can have negative impacts on human health, especially vulnerable populations. Several management practices can minimize risk of contamination of groundnut (Arachis hypogaea L.). A survey was conducted with thirty-six farmers who were involved in research designed to develop strategies to minimize aflatoxin contamination in groundnut in northern Ghana in 2017 and again in 2020. Fewer farmers in 2020 were consuming groundnuts with mold that produces aflatoxin or selling grain suspected of containing aflatoxin in local markets. Farmers increased use of tarpaulins as a drying surface in 2020 compared with 2017. Drying on tarpaulin has been shown to reduce aflatoxin contamination going into storage by minimizing spores on groundnut and enabling farmers to cover their crop when rain occurs after harvest and initial drying of pods. Hermetically-sealed bags limit fluctuations in humidity and can maintain groundnut moisture at optimum levels during storage. Farmers did not adopt hermetically-sealed bags to minimize aflatoxin, most likely because of availability and cost. Results from this longitudinal study provide knowledge on what aspects of aflatoxin mitigation after harvest need to be addressed in future research.

Genetic dissection of yield-related traits in response to drought stress in common bean

Drought stress severely impairs common bean production. For facilitating drought-resistance breeding in common bean, molecular markers were identified in a genome-wide level marker–trait association study. A panel of 210 common bean accessions showed large variation in 11 agronomic traits at the adult stage (plant height, pod number per plant, seed number per pod, seed number per plant, seed yield per plant, pod length, harvest index, pod harvest index, days to maturity, hundred-seed weight, and seed yield) under two water conditions. The coefficient of variation ranged from 6.21% for pod harvest index to 51.00% for seed number per plant under well-watered conditions, and from 4.05% for days to maturity to 40.72% for seed number per plant under drought stress. In a genome-wide association study, 119 quantitative-trait loci were associated with drought resistance, including 41 adjacent to known loci. Among these loci, 12 were found to be associated with at least two traits. Three major loci were identified at Pv01 and Pv02. A set of candidate genes were found that encode MYBs, AREBs, WKRYs, and protein kinases. These results reveal promising alleles that control drought resistance, shedding light on the genetic basis of drought resistance and accelerating future efforts for drought resistance improvement in common bean.

Simulating drought tolerance of peanut varieties by maintaining photosynthesis under water deficit

Over two-third of global peanuts are grown mainly in seasonally rainfed regions across arid and semi-arid zones where drought is a major yield limiting factor. Breeders are targeting drought adaptive traits by selecting high yielding genotypes under water-limited environments. Recently, several peanut varieties have been developed that exhibit drought tolerant characteristics. Crop models can be used to simulate the impact of these traits for different environments. The overall goal of this study was to develop an approach to simulate drought tolerant traits using the CROPGRO-Peanut model and assess the long-term yield response to these desired traits. Four peanut varieties and one advanced breeding line variety with varying degrees of drought tolerance response were grown under both field and rainout shelter conditions in 2019 and 2020. The trait of maintaining photosynthesis under water deficit was observed in the rainout shelter experiments and incorporated into the crop model as a new drought tolerance cultivar coefficient. The evaluation results with independent data showed that the modified model simulated peanut growth and yield under water-limited conditions reasonably well. The rainfed yield, seasonal evapotranspiration (ET), and grain water use efficiency (WUE) were simulated for both drought tolerant and baseline peanut varieties at two representative sites using weather data from 1998 to 2020. The drought tolerant mechanism of maintaining photosynthesis under water deficit was shown to be an advantageous trait for peanut varieties, which produced higher simulated rainfed yield with enhanced seasonal ET and grain WUE, especially for dry seasons. The simulated photosynthesis and yield were sensitive to values of the drought tolerant factor over an expected range of values. Further research is needed on other potential drought tolerant mechanisms, such as maintaining nitrogen fixation, pod harvest index and leaf growth under drought.

Effect of Conjoint Application of Inorganic and Organic Nutrient Sources on Yield and Economics of French Bean (Phaseolus vulgaris L.)

Background: French bean is an important legume vegetable crop. Due to its low ability to fix atmospheric nitrogen, excess amount of nitrogenous fertilizers are required by this crop as compared to other legumes. Overwhelming application of inorganic inputs has severely impacted environment and soil. So, there is a need to reduce inorganic inputs by adding organic nutrient sources. Methods: A three-year field experiment was laid comprising of eight treatment combinations and was replicated thrice during Kharif season of 2018, 2019 and 2020. Seeds of French bean cv. Green Wonder were sown at a spacing of 45 × 15 cm in each plot of size 3.0 m × 1.8 m. Recommended dose of fertilizers (NPK 50:100:50 kg ha-1) was followed as per different treatment details. Result: Application of 75 per cent NPK through inorganic and 25 per cent N through vermicompost resulted in minimum days to first pod harvest (61.89 days), maximum pod width (7.67 mm), number of pods per plant (30.96), plant height (51.29 cm), average pod weight (5.70 g), marketable pod yield (130.53 q ha-1) and highest benefit cost ratio (2.18) along with maximum net returns (Rs. 313061.43 ha-1).