Common Bean Phaseolus Vulgaris Research Articles

Strategy to identify common beans with resistance to white mould for dry‐irrigated areas: Additional evidence

AbstractIn a previous study, common bean (Phaseolus vulgaris L.) genotypes were selected in the field for reactions to white mould (WM), caused by Sclerotinia sclerotiorum. These genotypes, along with the resistant control A195, were then evaluated in both field and greenhouse (straw test) conditions. The results showed that field trials effectively identified high‐yielding WM‐resistant genotypes for dry‐irrigated conditions. Here we challenge the results of this study with new data and methodology by conducting six sprinkler‐irrigated trials from 2015 to 2017 with five genotype groups (G). Three groups comprised genotypes previously studied: G1, seven partially resistant; G4, two intermediately resistant; and G5, three susceptible. G2 consisted of four lines selected for partial resistance in the current study. The resistant control group, G3, comprised the genotypes A195, G122, Cornell605, and Ouro Branco. WM was absent (one trial), or pressure was either low/moderate (two trials) or moderate/high (three trials). The average seed yield ranged from 2207 (G3) to 3178 kg/ha (G1). The contrast G1, G2 versus G3 was nonsignificant for incidence and severity index, indicating that genotypes selected for resistance in the field were as resistant as the resistant control genotypes. Additionally, the groups selected for resistance yielded 43% more and produced 33% less sclerotia weight compared with the control group. Our results reinforce the effectiveness of selecting WM‐resistant genotypes using beans originally bred for purposes other than WM‐resistance, specifically targeting dry‐irrigated areas. Furthermore, our results suggest that the use of genotypes selected for partial resistance reduces inoculum levels in the soil.

Trichoderma harzianum enhances root biomass production and promotes lateral root growth of soybean and common bean under drought stress

AbstractDrought stress (DS) is one of the main environmental stresses that determines crop productivity. It has been estimated that DS depresses over 40%–60% of soybean (Glycine max (L.) Merr.) and common bean (Phaseolus vulgaris L.) production worldwide, respectively. Although different agronomic strategies are sometimes implemented, the current goal in sustainable agriculture could involve the inoculation with native microorganisms to mitigate DS effects. A potential fungal candidate is Trichoderma, which is recognized as a ubiquitous soil inhabitant with growth‐promoting and biocontrol potentiality. However, its potential for mitigating the stress for water deficit is less well‐documented. Our objective was to evaluate the effect of inoculation with native Trichoderma harzianum strains on soybean and common bean growth under contrasting conditions of water availability. Seeds were independently inoculated (or not) with IB‐J15 and IB‐363 strains, and plants were submitted to DS or were kept under optimal irrigation (well‐watered, WW). In both legumes, the most evident effect after being inoculated was the modification of plant root architecture, the increase in root area and the development of lateral roots in plants under WW and DS conditions. In soybean, both Trichoderma strains had a positive inoculation response, both fresh and dry root biomass increased under WW, and remarkably under DS conditions. The main effect was an increase of about 110% in root dry weight under WW and, about 330% in DS in plants inoculated with IB‐J15 strain, meanwhile, plants inoculated with IB‐363 increased root dry weight 60% in WW and 177% in DS conditions. Notably in soybean, the inoculation with both Trichoderma strains increased the root area more than 70% in both WW and DS conditions. Common beans inoculated with IB‐363 under WW conditions, reached a positive inoculation responsiveness of around 247% in shoot dry weight biomass, and under WW both strains increased the root area more than 50%. Further, IB‐363 increased leaf area by 25% in WW and 72% in DS. Additionally, the in vitro co‐culture between both Trichoderma strains and nodulating Rhizobium etli and Bradyrhizobium japonicum E109 showed compatibility between microorganisms, since no inhibition of their growth was observed. We emphasize that plants inoculated with Trichoderma showed better resistance to water deficit, as seen by redistribution of photosynthates, prioritizing mainly, the development of the root system. © 2024 Association of Applied Biologists.

Effects of NPSB Fertilizers Rate on the Yield of Common Bean (Phaseolus vulgaris L.) at Tocha District, Southern Ethiopia

Use of balanced nutrition means supplying other essential plant nutrients in adequate amount and proportion along with N and P. This implies N and P fertilizers are not the only yield determining nutrients but also S, B, and Cu nutrients are important nutrient for crop production. A trial was conducted in Tocha District to evaluate the rate of blended fertilizers to improve Common bean yield during main cropping season of 2019 and 2020. The experiment consists of seven treatment including (1) control, (2) NPSB: 18.9-37.7-6.95-0.1 (3) NPSB: 28.35-56.55-10.425-0.15 (4) NPSB: 37.8-75.4-13.9-0.2, (5) NPSB: 18.9-37.7-6.95-0.1+0.4kgCu, (6) NPSB: 28.35-56.55-10.425-0.15+0.4kgCu and (7) NPSB: 37.8-75.4-13.9-0.2+0.4kgCu. Soil physic chemical properties of the experimental site had moderately acidic, moderate level of OC and total N, high level of exchangeable K, very high level of CEC, low level of available P and clay loam textural class. In generally, application of blended fertilizer yielded better when compared with control. NPSB with the ratio of 37.8-75.4-13.9-0.2 (200kg NPSB) gave significantly optimum yield (4368.83 kg ha-1) compared to other treatments and also the highest net benefit (18725 ETB/ha) was obtained with acceptable marginal rate of return (MRR) (375.91%) which is more than the minimum acceptable MRR (100%) considered in this experiment. Similarly, NPSB 18.9-37.7-6.95-0.1 gave considerable net benefit with acceptable MRR. Therefore, based on the yield response and economic indicators, 200kg NPSB (37.8-75.4-13.9-0.2) is recommended as the best option and 100kg NPSB (18.9-37.7-6.95-0.1) as an alternative option for common bean producers at Tocha district and areas with the same soil conditions and agro-ecology.

Enhancing Bean (Phaseolus vulgaris L.) Resilience: Unveiling the Role of Halopriming against Saltwater Stress

Common bean (Phaseolus vulgaris L.), one of the most important cultivated legumes, requires a high level of water. It is included among the most sensitive species to climate change; drought and salinity cause a reduction in photosynthesis, metabolic and enzymatic alterations, and oxidative stress. To improve crop tolerance to salt, seed priming and acclimation can be useful tools. To test the salt tolerance of beans, a preliminary screening was undertaken on four cultivars of P. vulgaris (Black Turtle, Cargamanto, Bola Roja, Borlotto) by exposing the seeds to different levels of salinity. The salt-sensitive cultivar Borlotto was chosen for experimental greenhouse trials to study the effects of halopriming and acclimation. Primed and non-primed seeds were sown in non-saline soil and acclimated for 2 weeks; then, the plants were watered with non-saline and saline solutions for 4 weeks. At the end of this growth period, the primed plants showed a marked increase in salt stress tolerance, improving the chlorophyll content, phenolic compounds, and many enzymes’ activities, in turn reducing the effect of salt on growth and fruit production compared to the non-primed controls. In conclusion, halopriming can be considered a useful tool to enhance salinity tolerance in beans and other salt-sensitive crops.

OPTIMIZING ORGANIC AGRICULTURE: POULTRY MANURE DOMINATES IN ENHANCING GERMINATION AND GROWTH OF COMMON BEANS IN TANZANIA'S SEMI-ARID ENVIRONMENT

The study aimed to investigate the impact of different organic manures on the germination and growth performance of common beans (Phaseolus vulgaris L.) in Tanzania's semi arid region. Despite the widespread cultivation of common beans, limited research addresses the specific effects of diverse manure types on their germination and growth in this region. The primary objective is to assess and compare the influence of cow dung, poultry manure, rabbit manure, and a control (no manure) on common bean germination and growth. Understanding how different manure categories affect beans is crucial for optimizing agricultural practices in semi arid environments. A randomized block design was employed with four treatments (cow dung, poultry manure, rabbit manure, and control), each replicated three times. Common bean seeds were planted, and growth parameters, including plant height, leaf width, and leaf length, were measured. Data were analyzed using the Kruskal Wallis test and generalized linear models. Poultry manure consistently outperformed other categories, significantly enhancing bean germination and growth (P less than 0.05). The association between manure types and total germinated seeds was positive, with poultry and cow manures showing the most significant impact (P less than 0.05). Growth performance, especially plant height, demonstrated significant associations with manure type, plant parts' growth, time intervals, and distance from the bush. Poultry manure emerged as the most effective in promoting common bean germination and growth. The study highlights the need for tailored agricultural practices considering the diversity in manure effects. It suggests promoting organic farming practices, with an emphasis on poultry manure. Further research is encouraged to explore broader impacts on various crops. Educational initiatives are recommended to disseminate knowledge about organic manure benefits, and policy support is advocated to enhance soil fertility, crop yield, and environmental sustainability in Tanzanian agriculture.

Sex‐specific consequences of host shift for morphology and fluctuating asymmetry in a seed beetle: an experimental evolution approach

AbstractMorphological plasticity may be induced by altering host plants and commonly it is sex‐specific in phytophagous insects. It is hypothesized that stress in insects caused by a host shift leads to morphological changes and developmental destabilization, which may be identified by fluctuating asymmetry. We performed reciprocal transplant experiments in eight replicated populations of the seed beetle Acanthoscelides obtectus (Say) (Coleoptera: Chrysomelidae, Bruchinae) adapted to common bean (Phaseolus vulgaris L., Fabaceae) as its ancestral host and chickpea (Cicer arietinum L., Fabaceae) as a suboptimal host. Using methods of geometric morphometrics we assessed the effects of the short‐ and long‐term host shift on size and shape variation of beetles of both sexes. We also tested the hypothesis that fluctuating asymmetry is lower when the beetles develop within seeds of the ancestral host. Our results showed that females respond more plastically related to their body size and shape of the abdomen, particularly during a short‐term host shift, suggesting that females have a greater importance in maintaining the population on a new host. The level of fluctuating asymmetry is lowest in males that have evolved for generations on bean indicating that they have the most canalized development, so we suggested that symmetry in A. obtectus is maintained by sexual selection. Even if the beetles are adapted to a suboptimal host over many generations, they stabilize their development after returning to the ancestral host. Our work indicates that host shifts may change morphological aspects of the beetles in a sex‐specific manner and consequently influence their developmental trajectories.

Biological control potential of two Beauveria bassiana isolates against the stink bugs Nezara viridula L. and Piezodorus guildinii Westwood (Hemiptera: Pentatomidae) in common bean

BackgroundThe stink bugs, Nezara viridula L. and Piezodorus guildinii Westwood (Hemiptera: Pentatomidae) are the most important and widespread species of polyphagous stink bugs in the tropical and subtropical regions of Latin America, which affect the quality and yield of the common bean (Phaseolus vulgaris L.). The use of synthetic chemical insecticides is the major control strategy to manage stink bugs in common beans and alternatives are needed. In this study, mortality and median Lethal Time (LT50) of two Cuban isolates of the entomopathogenic fungus Beauveria bassiana (18 S-O-R and 96 P-O-E), as well as one commercial Cuban isolate (Bb-18), at a concentration of 1 × 108 conidia/ml were evaluated. These evaluations were conducted against both stink bug species using Petri dish bioassays and a semi-field experiment in common beans.ResultsIn Petri dish bioassays, the isolates 18 S-O-R and 96 P-O-E caused 100% mortality of both N. viridula and P. guildinii. This was significantly higher than for isolate Bb-18, which caused 86.3% N. viridula and 81.3% P. guildinii mortality. In the semi-field experiment, when pooling both stink bug species, total mortality after 14 days was 91.3% for 18 S-O-R, 80.0% for 96 P-O-E and 73.8% for Bb-18 isolates. LT50 value for isolate 18 S-O-R tested under laboratory conditions was 6.04 ± 0.18 days for N. viridula and 5.32 ± 0.14 days for P. guildinii at the same concentration of 1 × 108 conidia/ml. LT50 value for isolate 18 S-O-R in semi field was 6.79 ± 0.37 days for N. viridula and 7.71 ± 0.32 days for P. guildinii at 1 × 108 conidia/ml.ConclusionThe study highlights the potential of B. bassiana 18 S-O-R as a promising candidate for control of stink bugs in common bean under tropical conditions as an alternative to conventional chemical insecticides in integrated pest management (IPM) programs. Moving forward, further research should focus on validating the efficacy under diverse field conditions and integrating application methods into practical IPM approaches. Future use of B. bassiana will enhance sustainability and reduce environmental impacts associated with pesticide use.

Suppression of Root Rot Fungal Diseases in Common Beans (Phaseolus vulgaris L.) through the Application of Biologically Synthesized Silver Nanoparticles.

The biosynthesis of silver nanoparticles (AgNPs) using plant extracts has become a safe replacement for conventional chemical synthesis methods to fight plant pathogens. In this study, the antifungal activity of biosynthesized AgNPs was evaluated both in vitro and under greenhouse conditions against root rot fungi of common beans (Phaseolus vulgaris L.), including Macrophomina phaseolina, Pythium graminicola, Rhizoctonia solani, and Sclerotium rolfsii. Among the eleven biosynthesized AgNPs, those synthesized using Alhagi graecorum plant extract displayed the highest efficacy in suppressing those fungi. The findings showed that using AgNPs made with A. graecorum at a concentration of 100 μg/mL greatly slowed down the growth of mycelium for R. solani, P. graminicola, S. rolfsii, and M. phaseolina by 92.60%, 94.44%, 75.93%, and 79.63%, respectively. Additionally, the minimum inhibitory concentration (75 μg/mL) of AgNPs synthesized by A. graecorum was very effective against all of these fungi, lowering the pre-emergence damping-off, post-emergence damping-off, and disease percent and severity in vitro and greenhouse conditions. Additionally, the treatment with AgNPs led to increased root length, shoot length, fresh weight, dry weight, and vigor index of bean seedlings compared to the control group. The synthesis of nanoparticles using A. graecorum was confirmed using various physicochemical techniques, including UV spectroscopy, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) analysis. Collectively, the findings of this study highlight the potential of AgNPs as an effective and environmentally sustainable approach for controlling root rot fungi in beans.

Building the Resilience of Marginal Rural Areas Using a Complementary Characterization Approach: Possible Beneficial Health Effects and Stress Tolerance of Italian Common Bean (Phaseolus vulgaris L.) Landraces

Building the Resilience of Marginal Rural Areas Using a Complementary Characterization Approach: Possible Beneficial Health Effects and Stress Tolerance of Italian Common Bean (Phaseolus vulgaris L.) Landraces

Factors Influencing the Emergence of Heterogeneous Populations of Common Bean (Phaseolus vulgaris L.) and Their Potential for Intercropping.

The common bean is an important legume valued for its protein-rich seeds and its ability to fix nitrogen, making it a key element of crop rotation. In conventional agriculture, the emphasis is on uniformity and genetic purity to optimize crop performance and maximize yields. This is due to both the legal obligations to register varieties and the challenges of implementing breeding programs to create genetically diverse varieties. This paper focuses on the factors that influence the occurrence of heterogeneous common bean populations. The main factors contributing to this diversity have been described, including local adaptations, variable weather conditions, different pollinator species, and intricate interactions between genes controlling seed coat colour. We also discuss the benefits of intercropping common beans for organic farming systems, highlighting the improvement in resistance to diseases, and adverse environmental conditions. This paper contributes to a better understanding of common bean seed heterogeneity and the legal obligation to use heterogeneous populations.

Botanical extracts control the fungal pathogen Colletotrichum boninense in smallholder production of common bean

Anthracnose caused by Colletotrichum spp. remains an intractable problem in the most common bean (Phaseolus vulgaris) production areas worldwide and can cause total yield loss. Many smallholder farmers are familiar with using botanical extracts to control insect pests; however, there is less familiarity with their use to control fungal diseases due to a lack of evidence. Here, we demonstrate that anthracnose could be controlled effectively by pesticidal plant species that are used for insect control. In laboratory trials, water extracts from 11 plant species could inhibit fungal growth (100%) and spore germination (75–100%) equally well to two commercially available fungicides, the synthetic Mancolaxyl and biofungicide Bioderma. In screenhouse trials, anthracnose disease was reduced by the extracts of three plant species. Moreover, bean crop growth in these botanical treatments did not differ significantly from that observed in the commercial fungicide treated plants. Field trials in a smallholder community reporting severe problems with anthracnose showed an effect similar to the screenhouse results. Field trials resulted in bean seed yields approximately 350 kg/ha higher in bean plants treated with Azadirachta indica and Lippia javanica at 10% w/v compared to the negative control untreated plants. In all trials, botanical extracts were as effective as commercially available fungicides, suggesting that these botanical extracts could provide dual-purpose pest and disease management for anthracnose and crop pest insects. The outcomes of this research show that prospects for using locally available resources to control anthracnose on common bean are credible and can be combined with controlling insect pests.

A Past Genetic Bottleneck from Argentine Beans and a Selective Sweep Led to the Race Chile of the Common Bean (Phaseolus vulgaris L.).

The domestication process of the common bean gave rise to six different races which come from the two ancestral genetic pools, the Mesoamerican (Durango, Jalisco, and Mesoamerica races) and the Andean (New Granada, Peru, and Chile races). In this study, a collection of 281 common bean landraces from Chile was analyzed using a 12K-SNP microarray. Additionally, 401 accessions representing the rest of the five common bean races were analyzed. A total of 2543 SNPs allowed us to differentiate a genetic group of 165 accessions that corresponds to the race Chile, 90 of which were classified as pure accessions, such as the bean types 'Tórtola', 'Sapito', 'Coscorrón', and 'Frutilla'. Our genetic analysis indicates that the race Chile has a close relationship with accessions from Argentina, suggesting that nomadic ancestral peoples introduced the bean seed to Chile. Previous archaeological and genetic studies support this hypothesis. Additionally, the low genetic diversity (π = 0.053; uHe = 0.53) and the negative value of Tajima' D (D = -1.371) indicate that the race Chile suffered a bottleneck and a selective sweep after its introduction, supporting the hypothesis that a small group of Argentine bean genotypes led to the race Chile. A total of 235 genes were identified within haplotype blocks detected exclusively in the race Chile, most of them involved in signal transduction, supporting the hypothesis that intracellular signaling pathways play a fundamental role in the adaptation of organisms to changes in the environment. To date, our findings are the most complete investigation associated with the origin of the race Chile of common bean.

Genetic analysis of scab disease resistance in common bean (Phaseolus vulgaris) varieties using GWAS and functional genomics approaches

IntroductionScab is a fungal disease of common beans caused by the pathogen Elsinoë phaseoli. The disease results in major economic losses on common beans, and there are efforts to develop integrated pest management strategies to control the disease. Modern computational biology and bioinformatics tools were utilized to identify scab disease resistance genes in the common bean by identification of genomic regions and genes associated with resistance to scab disease during natural infection in the field.MethodsA diverse set of common bean accessions were analyzed for genetic association with scab disease resistance using a Genome-Wide Association Study design of infected plants and non-infected plants (controls). A fixed and random model circulating probability unification model of these two covariates that considers a minor allele frequency threshold value of 0.03 were deployed during the analysis. Annotation of genes proteins with significant association values was conducted using a machine learning algorithm of support vector machine on prPred using python3 on Linux Ubuntu 18.04 computing platform with an accuracy of 0.935.ResultsCommon bean accessions tested showed varying phenotypes of susceptibility to scab disease. Out of 179 accessions, 16 and 163 accessions were observed to be resistant and susceptible to scab disease, respectively. Genomic analysis revealed a significant association on chromosome one SNP S1_6571566 where the protein-coding sequence had a resistant possibility of 55% and annotated to the Enhancer of Poly-comb like protein.ConclusionThe significant differences in the phenotypic variability for scab disease indicate wide genetic variability among the common bean accessions. The resistant gene associated with scab disease was successfully identified by GWAS analysis. The identified common bean accessions resistant to scab disease can be adopted into breeding programs as sources of resistance.

Ozone pollution contributes to the yield gap for beans in Uganda, East Africa, and is co-located with other agricultural stresses

Air quality negatively impacts agriculture, reducing the yield of staple food crops. While measured data on African ground-level ozone levels are scarce, experimental studies demonstrate the damaging impact of ozone on crops. Common beans (Phaseolus vulgaris), an ozone-sensitive crop, are widely grown in Uganda. Using modelled ozone flux, agricultural surveys, and a flux-effect relationship, this study estimates yield and production losses due to ozone for Ugandan beans in 2015. Analysis at this scale allows the use of localised data, and results can be presented at a sub-regional level. Soil nutrient stress, drought, flood risk, temperature and deprivation were also mapped to investigate where stresses may coincide. Average bean yield losses due to ozone were 17% and 14% (first and second growing season respectively), equating to 184 thousand tonnes production loss. However, for some sub-regions, losses were up to 27.5% and other crop stresses also coincided in these areas. This methodology could be applied widely, allowing estimates of ozone impact for countries lacking air quality and/or experimental data. As crop productivity is below its potential in many areas of the world, changing agricultural practices to mitigate against losses due to ozone could help to reduce the crop yield gap.

Phenotypic and yield responses of common bean (Phaseolus vulgaris l.) varieties to different soil moisture levels

BackgroundMorphological plasticity is one of the capacities of plants to modify their morphological appearance in response to external stimuli. A plant’s morphology and physiology are constantly tuned to its variable surroundings by complex interactions between environmental stimuli and internal signals.In most of plant species,, such phenotypic and physiological expression varies among different varieties based on their levels of particular environmental stress conditions. However, the morphological and yield responses of common bean varieties to different environmental conditions are not well known. The purpose of the study was to evaluate morphological and yield response of common bean to soil moisture stress and to investigate the morphological mechanism by which common bean varieties tolerate fluctuations in moisture stress.MethodsA pot experiment was carried out to investigate the effects of different moisture levels on the phenotypic and yield responses of common bean varieties. A factorial combination of five common bean varieties (Hirna, kufanzik, Awash-1, Ado, and Chercher) and three moisture levels (control, waterlogging stress, and moisture deficit stress) was used in three replications. Moisture stress treatments were started 20 days after planting, at the trifoliate growth stage. To evaluate the response of each variety, morphological and yield data were collected at week intervals.Main resultsThe results indicated that moisture levels and varieties had a significant influence on all growth parameters. Crop phenology was significantly influenced by the interaction effect of moisture level and variety. Exposing Hirna variety to moisture stress led to extended flowering and pod setting by 23 and 24 days, respectively, compared to the other treatments. The results showed that the phenotypic responses to moisture deficit and waterlogging stress varied between varieties. Waterlogging stress had a stronger reduction effect on the fresh weight, dry weight and leaf area of common bean varieties than moisture deficit and the control. Pods per plant, seeds per plant, grain yield per plant, and harvest index were significantly influenced by the varieties, moisture stress levels and their interaction. Except for Chercher and Hirna. However, varieties Ado, kufanzik and Awasha-1 did not show significant differences on the time of flower initiation due to moisture level. Biomass and growth in leaf fresh weight, leaf dry weight, leaf area, leaf number and plant height were significantly influenced by moisture level. When moisture deficit and waterlogging stress occurred, Ado and Awash-1 were more responsive to moisture stress than Hirna, Chercher, and Kufanzik.ConclusionHence, Hirna and Kufanzik varieties were found to be tolerant because they produced higher yields than the Chercher, Awash-1, and Ado varieties.

Metabolomics of common bean (Phaseolus vulgaris L.) antixenosis to the Mexican weevil (Zabrotes subfasciatus Boh.)

Metabolomics of common bean (Phaseolus vulgaris L.) antixenosis to the Mexican weevil (Zabrotes subfasciatus Boh.)

Geotechnologies in Biophysical Analysis through the Applicability of the UAV and Sentinel-2A/MSI in Irrigated Area of Common Beans: Accuracy and Spatial Dynamics

The applicability of remote sensing enables the prediction of nutritional value, phytosanitary conditions, and productivity of crops in a non-destructive manner, with greater efficiency than conventional techniques. By identifying problems early and providing specific management recommendations in bean cultivation, farmers can reduce crop losses, provide more accurate and adequate diagnoses, and increase the efficiency of agricultural resources. The aim was to analyze the efficiency of vegetation indices using remote sensing techniques from UAV multispectral images and Sentinel-2A/MSI to evaluate the spectral response of common bean (Phaseolus vulgaris L.) cultivation in different phenological stages (V4 = 32 DAS; R5 = 47 DAS; R6 = 60 DAS; R8 = 74 DAS; and R9 = 89 DAS, in 99 days after sowing—DAS) with the application of doses of magnesium (0, 250, 500, and 1000 g ha−1). The field characteristics analyzed were mainly chlorophyll content, productivity, and plant height in an experimental area by central pivot in the midwest region of Brazil. Data from UAV vegetation indices served as variables for the treatments implemented in the field and were statistically correlated with the crop’s biophysical parameters. The spectral response of the bean crop was also detected through spectral indices (NDVI, NDMI_GAO, and NDWI_GAO) from Sentinel-2A/MSI, with spectral resolutions of 10 and 20 m. The quantitative values of NDVI from UAV and Sentinel-2A/MSI were evaluated by multivariate statistical analysis, such as principal components (PC), and cophenetic correlation coefficient (CCC), in the different phenological stages. The NDVI and MCARI vegetation indices stood out for productivity prediction, with r = 0.82 and RMSE of 330 and 329 kg ha−1, respectively. The TGI had the best performance in terms of plant height (r = 0.73 and RMSE = 7.4 cm). The best index for detecting the relative chlorophyll SPAD content was MCARI (r = 0.81; R2 = 0.66 and RMSE = 10.14 SPAD), followed by NDVI (r = 0.81; R2 = 0.65 and RMSE = 10.19 SPAD). The phenological stage with the highest accuracy in estimating productive variables was R9 (Physiological maturation). GNDVI in stages R6 and R9 and VARI in stage R9 were significant at 5% for magnesium doses, with quadratic regression adjustments and a maximum point at 500 g ha−1. Vegetation indices based on multispectral bands of Sentinel-2A/MSI exhibited a spectral dynamic capable of aiding in the management of bean crops throughout their cycle. PCA (PC1 = 48.83% and PC2 = 39.25%) of the satellite multiple regression model from UAV vs. Sentinel-2A/MSI presented a good coefficient of determination (R2 = 0.667) and low RMSE = 0.12. UAV data for the NDVI showed that the Sentinel-2A/MSI samples were more homogeneous, while the UAV samples detected a more heterogeneous quantitative pattern, depending on the development of the crop and the application of doses of magnesium. Results shown denote the potential of using geotechnologies, especially the spectral response of vegetation indices in monitoring common bean crops. Although UAV and Sentinel-2A/MSI technologies are effective in evaluating standards of the common bean crop cycle, more studies are needed to better understand the relationship between field variables and spectral responses.

Genetic and pathogenic characterization of Rhizoctonia solani AG-4 isolates obtained from common bean

Common bean (Phaseolus vulgaris L.) is the most important grain legume. Crop production of common bean is affected by a number of diseases, such as Rhizoctonia root rot, being detected worldwide. Herein, we aimed to genetically and pathologically characterize Rhizoctonia solani isolates obtained from different provinces in Turkey. Anastomosis groups (AG) and subgroups of isolates were identified based on the sequence analysis of the rDNA-ITS region. The most prevalent subgroup was AG-4 HGIII, according to BLAST analysis and the phylogeny of resultant sequences, followed by AG-4 HGI and AG-4 HGII, respectively. iPBS retrotransposons highly supported the phylogenetic tree and provided a high level of genetic variability among isolates to discriminate AG subgroups. The results indicated that the iPBS DNA marker system based on retrotransposons could be used to discriminate Rhizoctonia isolates relying on AG grouping. The virulence of the pathogen isolates changed from 3.67 to 5 based on the agar-plate assay on the susceptible cv. Gina. The reactions of thirty common bean cultivars were also evaluated against the most aggressive isolate in each subgroup. The reaction assay showed significant differences among both isolates and cultivars; the highest disease severity among cultivars was observed to AG-4 HGI, followed by AG-4 HGIII and AG-4 HGII, respectively. None of the cultivars showed resistance to all AG subgroups. Screening of AGs among the isolates and selecting cultivars are critical to managing Rhizoctonia disease due to the range of host suitability according to AG subgroups.

Determination of combining ability and heritability for canning quality traits in common bean

Breeding for common bean (Phaseolus vulgaris L.) genotypes with optimal canning quality holds the potential for increased dry bean consumption among middle-class income urban dwellers in sub-Saharan Africa (SSA). Understanding the genetic control of canning quality traits is central for the improvement of common bean genotypes for desired canning quality. The objective of this study was to determine the combining ability and heritability of canning quality traits (CQTs) in common bean; and to establish entry points for effective breeding for these traits. A population from two contrasting parents for canning quality traits was developed and progressed to F2. The F2:F4 seed was evaluated for CQTs at three months post-harvest. Substantial variation was observed among the canning quality traits tested, including the general appearance of the canned beans, seed coat colour retention namely, clumping, free starch, splitting, and hydration coefficient. Canning quality traits encompassed a spectrum of both additive and non-additive effects. Promising combiners for CQTs were identified among the parents, KK8 and MAC 13, suggesting their potential for utilisation in breeding programmes. Moderate to high Baker’s ratio (BR = 0.41-0.94) values were observed for some CQTs and narrow sense heritability (h2 = 0.47-0.66). Canning quality traits exhibited substantial broad sense heritability (H2) values, ranging from 0.6 to 0.92. These findings provide valuable entry points for breeding programmes focused on improving common bean for canning quality.

Common bean under different water availability reveals classifiable stimuli-specific signatures in plant electrome

ABSTRACT Plant electrophysiology has unveiled the involvement of electrical signals in the physiology and behavior of plants. Spontaneously generated bioelectric activity can be altered in response to changes in environmental conditions, suggesting that a plant’s electrome may possess a distinct signature associated with various stimuli. Analyzing electrical signals, particularly the electrome, in conjunction with Machine Learning (ML) techniques has emerged as a promising approach to classify characteristic electrical signals corresponding to each stimulus. This study aimed to characterize the electrome of common bean (Phaseolus vulgaris L.) cv. BRS-Expedito, subjected to different water availabilities, seeking patterns linked to these stimuli. For this purpose, bean plants in the vegetative stage were subjected to the following treatments: (I) distilled water; (II) half-strength Hoagland’s nutrient solution; (III) −2 MPa PEG solution; and (IV) −2 MPa NaCl solution. Electrical signals were recorded within a Faraday’s cage using the MP36 electronic system for data acquisition. Concurrently, plant water status was assessed by monitoring leaf turgor variation. Leaf temperature was additionally measured. Various analyses were conducted on the electrical time series data, including arithmetic average of voltage variation, skewness, kurtosis, Probability Density Function (PDF), autocorrelation, Power Spectral Density (PSD), Approximate Entropy (ApEn), Fast Fourier Transform (FFT), and Multiscale Approximate Entropy (ApEn(s)). Statistical analyses were performed on leaf temperature, voltage variation, skewness, kurtosis, PDF µ exponent, autocorrelation, PSD β exponent, and approximate entropy data. Machine Learning analyses were applied to identify classifiable patterns in the electrical time series. Characterization of the electrome of BRS-Expedito beans revealed stimulus-dependent profiles, even when alterations in water availability stimuli were similar in terms of quality and intensity. Additionally, it was observed that the bean electrome exhibits high levels of complexity, which are altered by different stimuli, with more intense and aversive stimuli leading to drastic reductions in complexity levels. Notably, one of the significant findings was the 100% accuracy of Small Vector Machine in detecting salt stress using electrome data. Furthermore, the study highlighted alterations in the plant electrome under low water potential before observable leaf turgor changes. This work demonstrates the potential use of the electrome as a physiological indicator of the water status in bean plants.