Search Results (10)

Grain legumes play a significant global role and are integral to agriculture and food production worldwide. Therefore, comprehending and analyzing the factors that influence grain legume yield are of paramount importance for guiding agricultural management and decision making. Traditional statistical analysis methods present limitations in interpreting results, but explainable artificial intelligence (AI) provides a visual representation of model results, offering insights into the key factors affecting grain legume yield. In this study, nine typical grain legume species were selected from a published global experimental dataset: garden pea (Pisum sativum), chickpea (Cicer arietinum), cowpea (Vigna unguiculata), garden vetch (Vicia sativa), faba bean (Vicia faba), lentil (Lens culinaris), pigeon pea (Cajanus cajan), peanut (Arachis hypogaea), and white lupine (Lupinus albus). Seven commonly used models were constructed for each legume species, and model performance evaluation was conducted using accuracy, AUC, recall, precision, and F1 score metrics. The best classification model was selected for each grain legume species. Employing Decision Tree analysis, Feature Importance Evaluation, and SHapley Additive exPlanations (SHAP) as explainable techniques, our study conducted both individual and comprehensive analyses of nine leguminous crops. This approach offers a novel perspective, unveiling not only the unique responses of each crop to the influencing factors but also demonstrating the common factors across different crops. According to the experimental results, XGboost (XGB) and Random Forests (RF) are the best-performing models among the nine types of grain legumes, and the classification accuracy of a specific species is as high as 87.33%. Insights drawn from the feature importance map reveal that several factors, including aerial biomass, precipitation, sunshine duration, soil conditions, growth cycle, and fertilization strategy, have a pivotal influence. However, it was found from the SHAP graph that the responses of various crops to these factors are not the same. This research furnishes novel perspectives and insights into understanding the factors influencing grain legume yields. The findings provide a robust scientific foundation for agricultural managers, experts, and policymakers in the pursuit of optimizing pulse yields and advancing agricultural sustainability. Full article

Sub-Saharan African smallholder farmers face challenges due to limited access to commercial fertilizers, affecting food security. Exploring the benefits of intercropping is promising, but evaluating crop performance in specific agroecological contexts is crucial. This study in Vilankulo, Mozambique, conducted over two growth seasons (2018 and 2019), aimed to assess the benefits of intercropping maize (Zea mays L.) and cowpea (Vigna unguiculata L., Walp) (M+C) compared to maize (M) and cowpea (C) as sole crops. Key variables for comparison included dry matter yield (DMY), land equivalent ratio (LER), competitive ratio (CR), tissue nutrient concentration, nutrient recovery, and apparent N fixation (ANF). This study also examined the effects on cabbage (Brassica oleracea L.), cultivated as a succeeding crop, and soil properties. In 2018, maize plants were severely affected by drought and did not produce grain. This year, cowpea grain yields were 2.26 and 1.35 t ha⁻¹ when grown as sole crop or intercropped. In 2019, maize grain yield was 6.75 t ha⁻¹ when intercropped, compared to 5.52 t ha⁻¹ as a sole crop. Cowpea grain yield was lower when intercropped (1.51 vs. 2.25 t ha⁻¹). LER values exceeded 1 (1.91 and 1.53 for grain and straw in 2019), indicating improved performance in intercropping compared to sole crops. In 2019, CR was 1.96 for maize grain and 0.58 for cowpea grain, highlighting the higher competitiveness of maize over cowpea. Cowpea exhibited higher average leaf nitrogen (N) concentration (25.4 and 37.6 g kg⁻¹ in 2018 and 2019, respectively) than maize (13.0 and 23.7 g kg⁻¹), attributed to its leguminous nature with access to atmospheric N, benefiting the growth of maize in intercropping and cabbage cultivated as a succeeding crop. Cowpea also appears to have contributed to enhanced phosphorus (P) absorption, possibly due to access to sparingly soluble P forms. In 2019, ANF in M+C was 102.5 kg ha⁻¹, over 4-fold higher than in C (25.0 g kg⁻¹), suggesting maize accessed more N than could cowpea provide, possibly through association with endophytic diazotrophs commonly found in tropical grasses. Full article

Identifying cultivars of leguminous crops exhibiting drought resistance has become crucial in addressing water scarcity issues. This investigative study aimed to select soybean and cowpea cultivars with enhanced potential to grow under water restriction during the vegetative stage. Two parallel trials were conducted using seven soybean (AS3810IPRO, M8644IPRO, TMG1180RR, NS 8338IPRO, BMX81I81IPRO, M8808IPRO, and BÔNUS8579IPRO) and cowpea cultivars (Aracê, Novaera, Pajeú, Pitiúba, Tumucumaque, TVU, and Xique-xique) under four water levels (75, 60, 45, and 30% field capacity—FC) over 21 days. Growth, water content, membrane damage, photosynthetic pigments, organic compounds, and proline levels were analyzed. Drought stress significantly impacted the growth of both crops, particularly at 45 and 30% FC for soybean and 60 and 45% FC for cowpea plants. The BÔNUS8579IPRO and TMG1180RR soybean cultivars demonstrated the highest performance under drought, a response attributed to increased amino acids and proline contents, which likely help to mitigate membrane damage. For cowpea, the superior performance of the drought-stressed Xique-xique cultivar was associated with the maintenance of water content and elevated photosynthetic pigments, which contributed to the preservation of the photosynthetic efficiency and carbohydrate levels. Our findings clearly indicate promising leguminous cultivars that grow under water restriction, serving as viable alternatives for cultivating in water-limited environments. Full article

Endophytic microbiota are being researched as a vital source of beneficial attributes that are of immense importance for enhancing agroecological crop production. In this study, two endophytic strains: Pseudomonas carnis NWUBe30 and Stenotrophomonas geniculata NWUBe21, were isolated from cowpea tissue, and their plant growth-promoting attributes were assessed. The 16S rRNA gene, as well as the key plant growth-promoting genes that they contain, were subjected to polymerase chain reactions (PCR). Furthermore, their genome was sequenced using the Illumina NovaSeq 6000 systems platform. The results indicated that they possess multiple plant growth-promoting attributes, including the solubilization of phosphates, the production of auxin, siderophore, hydrogen cyanide, exopolysaccharide, ammonia, and 1-aminocyclopropane-1-carboxylic acids. Additionally, the plant growth-promoting genes GCD and ASB were amplified via PCR at their expected base pair value. The genome bioinformatics analysis revealed assembled sizes of 5,901,107 bp for P. carnis NWUBe30, with an average G+C content of 60.2%, and for S. geniculata NWUBe21, 512,0194 bp, with a G+C content of 64.79%. Likewise, genes, such as exopolyphosphatase, ferribacilibactin, betalactone, and lassopeptide, that are responsible for promoting plant growth were identified. This study highlights the biotechnological potential of Stenotrophomonas geniculata strain NWUBe21 and the Pseudomonas carnis strain NWUBe30, which can be harnessed to achieve improvements in sustainable agroecological crop production. Full article

Cashew is an important export-oriented crop in several tropical countries, often under monocropping systems. Intercropping with legume species is promoted as a sustainable practice, enhancing agricultural productivity and providing nutritional food sources to rural communities. This study aimed to characterize the diversity of Leguminosae (or Fabaceae) in the cashew agroforestry systems of East Timor (Southeast Asia). Fourteen cashew orchards were sampled across the country, and information about leguminous species uses was collected from local populations. About 50 species are commonly part of the country’s cashew agroforestry system, many of them simultaneously used as food, fodder, and in traditional medicine. Six bean species—Cajanus cajan (L.) Huth, Phaseolus lunatus L., Phaseolus vulgaris L., Vigna angularis (Willd.) Ohwi and H.Ohashi, Vigna radiata (L.) R.Wilczek and Vigna unguiculata (L.) Walp.—are largely used as food. The mineral contents of these beans revealed relevant differences between species and, in some cases, between types (seed colour) within species. Periods of hunger and low food variety are frequent in East Timor, reflecting a very poor nutritional state of the population. Knowing and using legumes for local nutrition, as well as for healthcare and well-being, adds great value to these species as components of East Timor cashew agroforestry systems. Full article

Cowpea (Vigna unguiculata (L.) Walp.) is a leguminous species widely cultivated in northern and northeastern Brazil. In the state of Pará, this crop still has low productivity due to several factors, such as low soil fertility and climatic adversity, especially the water deficiency. Therefore, the present study aimed at evaluating the physiological parameters and the productivity of cowpea plants under different water depths. The experiment was conducted in Castanhal/Pará between 2015 and 2016. A randomized block design was applied with six replications and four treatments, represented by the replacement of 100%, 50%, 25% and 0% of the water lost during crop evapotranspiration (ETc), starting from the reproductive stage. The rates of net photosynthesis (A), stomatal conductance (gs), leaf transpiration (E_leaf), substomatal CO₂ concentration (Ci), leaf temperature (T_leaf) and leaf water potential (Ψ_w) were determined in four measurements at the R5, R7, R8 and R9 phenological stages. Cowpea was sensitive to the water availability in the soil, showing a significant difference between treatments for physiological variables and productivity. Upon reaching a Ψ_w equal to −0.88 MPa, the studied variables showed important changes, which allows establishing this value as a threshold for the crop regarding water stress under such experimental conditions. The different water levels in the soil directly influenced productivity for both years, indicating that the proper water supply leads to better crop growth and development, increasing productivity. Full article

Cowpea is a multiple-purpose drought-tolerant leguminous pulse crop grown in several dry tropical areas. Its domestication center is thought to be East or West Africa, where a high level of genetic diversity is apparently still found. However, detailed genetic information is lacking in many African countries, limiting the success of breeding programs. In this work, we assessed the genetic variation and gene flow in 59 Vigna unguiculata (cowpea) accessions from 10 landraces spanning across six agro-ecological zones of Mozambique, based on nuclear microsatellite markers. The results revealed the existence of high genetic diversity between the landraces, even in comparison to other world regions. Four genetic groups were found, with no specific geographic pattern, suggesting the presence of gene flow between landraces. In comparison, the two commercial varieties had lower values of genetic diversity, although still close to the ones found in local landraces. The high genetic diversity found in Mozambique sustains the importance of local genetic resources and farm protection to enhance genetic diversity in modern varieties of cowpea worldwide. Full article

Nitrous oxide (N₂O) emission from denitrification in agricultural soils often increases with nitrogen (N) fertilizer and soil nitrate (NO₃⁻) concentrations. Our hypothesis is that legume cover crops can improve efficiency of N fertilizer and can decrease N₂O emissions compared to non–cover crop systems. The objectives of this study were to (a) evaluate the performance of summer leguminous cover crops in terms of N uptake and carbon (C) accumulation following winter wheat and (b) to quantify the effects of summer leguminous cover crops and N fertilizer rates on N₂O emissions and grain yield of the subsequent grain sorghum crop. Field experiments were conducted in the context of a wheat-sorghum rotation for two seasons in Kansas. Treatments consisted of double-cropped leguminous cover crops following winter wheat harvest with no fertilizer applied to the following grain sorghum or no cover crop after wheat harvest and N fertilizer rates applied to the grain sorghum. The cover crops were cowpea (Vigna unguiculata L. Walp.), pigeon pea (Cajanus cajan L. Millsp.), and sunn hemp (Crotalaria juncea L.). The three N treatments (were 0, 90, and 180 kg·N·ha⁻¹). Fallow systems with 90 and 180 kg·N·ha⁻¹ produced significantly greater N₂O emissions compared with cropping systems that received no N fertilizer. Emissions of N₂O were similar for various cover crops and fallow systems with 0 kg·N·ha⁻¹. Among cover crops, pigeon pea and cowpea had greater C accumulation and N uptake than sunn hemp. Grain yield of sorghum following different cover crops was similar and significantly higher than fallow systems with 0 kg·N·ha⁻¹. Although fallow systems with 90 and 180 kg·N·ha⁻¹ produced maximum sorghum grain yields, N₂O emissions per unit of grain yield decreased as the amount of N fertilizer was reduced. We conclude that including leguminous cover crops can decrease N fertilizer requirements for a subsequent sorghum crop, potentially reducing N₂O emissions per unit grain yield and providing options for adaptation to and mitigation of climate change. Full article

Sugarcane is commercially produced on 340,000 ha in the US and is valued at over $1 billion US annually. Cultural practices that improve sugarcane sustainability are needed to maintain yields in fields with degraded soils. Historically, leguminous rotation crops provided organic matter and biologically fixed nitrogen (N) for subsequent sugarcane crops. Currently, sugarcane is usually grown as a monoculture with only a short, 6-month fallow period. The objective of these field studies was to determine how growing cowpea (Vigna unguiculata (L.) Walp.) and sunn hemp (Crotalaria juncea L.) as cover crops during fallow affected the yield of subsequent sugarcane crops. A companion laboratory study investigated the decomposition rate of cover crops in soil at different temperatures. Cowpea and sunn hemp production produced 12.8 t/ha dry matter and 250 kg N/ha. Cowpea generally improved plant cane yields, but the effects of sunn hemp varied. However, neither cowpea nor sunn hemp reduced cane or sucrose yields consistently, and mineral N additions may have a role in mitigating yield gains or losses. Based on laboratory data, the average half-life for cowpea and sunn hemp would be 3 months. Overall, using legume cover crops should be viewed as an important component of sustainable sugarcane practices. Full article

Many farms use leguminous cover crops as a nutrient management strategy to reduce their need for nitrogen fertilizer. When they are effective, leguminous cover crops are a valuable tool for sustainable nutrient management. However, the symbiotic partnership between legumes and nitrogen fixing rhizobia is vulnerable to several abiotic and biotic stressors that reduce nitrogen fixation efficiency in real world contexts. Sometimes, despite inoculation with rhizobial strains, this symbiosis fails to form. Such failure was observed in a 14-acre winter cover crop trial in the Rio Grande Valley (RGV) of Texas when three legume species produced no signs of nodulation or nitrogen fixation. This study examined the role of nitrogen, phosphorus, moisture, micronutrients, and native microbial communities in the nodulation of cowpea (Vigna unguiculata L. Walp) and assessed arbuscular mycorrhizal fungi as an intervention to improve nodulation. Results from two controlled studies confirm moisture and native microbial communities as major factors in nodulation success. Micronutrients showed mixed impacts on nodulation depending on plant stress conditions. Nitrogen and phosphorus deficiencies, however, were not likely causes, nor was mycorrhizal inoculation an effective intervention to improve nodulation. Inoculation method also had a major impact on nodulation rates. Continued research on improved inoculation practices and other ways to maximize nitrogen fixation efficiency will be required to increase successful on-farm implementation. Full article