Bean Improvement Research Articles

Genotype-Specific Responses of Common Bean to Meloidogyne incognita.

The root-knot nematode Meloidogyne incognita causes large galls on roots, interfering with the flow of water and nutrients to the plant. In the common bean, no major resistance (R) genes have been described. Instead, resistance is controlled by multiple genes, which have not proved effective so far. An RNA-seq approach was used to identify genes involved in common bean response to M. incognita at the stages of nematode invasion and root-galling. When comparing infected and uninfected treatments of a moderately resistant (MR) and a susceptible (S) genotype, several genes were identified as differentially expressed. Their functional annotation indicated that both genotypes underwent complex transcriptional reprogramming from early to later periods of the interaction, but defense-related genes were mostly upregulated in the MR genotype. At the early stage, a large set of genes was activated in both genotypes, including those involved in cell wall organization, signaling, hormonal pathways, transcription factors, oxidative stress and putative resistance gene analogs. Later, most of the previously activated defense mechanisms were no longer expressed in the S genotype. There was an increased expression of genes encoding proteins involved in hormonal signaling pathways (salicylic acid and gibberellin-related), protein kinases, transcription factors and oxidative stress in MR. However, a decreased expression of genes involved in signaling mediated by calcium and oxidative stress occurred in S, indicating susceptibility. The repertoire of genes identified herein will facilitate research in plant-nematode interactions, with possible applications for the improvement of the common bean.

Inheritance of Drought Tolerance in a F3 Biparental Population of Pinto Saltillo (Phaseolus vulgaris L.) × Tepary Cafe (Phaseolus acutifolius A. Gray)

Drought is the most significant negative factor affecting common bean (Phaseolus vulgaris L.) production. Scarce studies about the genetic control of drought tolerance in beans impedes a more effective exploitation of these traits in plant breeding. The Tepary bean (Phaseolus acitifolius A. Gray) is considered a valuable source of drought-resistant genes for improving commercial varieties that are susceptible to drought. The main objective of this study was to evaluate the germination and seedling growth components in response to drought stress simulated with polyethylene glycol (PEG-6000). We developed a F3 biparental population from the cross between the susceptible P-saltillo variety and drought-tolerant T-cafe, which allowed the study of drought-tolerance genetics in beans. The F3 biparental population showed wide variability for the traits studied, i.e., from 0.0 to 2.4 for hypocotyl length, from 0.3 to 3.9 and 7.5 to 97.5 for germinated seeds (n and % hypocotyls, respectively), from 0.3 to 3.9 and 7.5 to 97.5 for germinated seeds (n and % roots, respectively), from 0.3 to 4.5 for root length, and from 0.0 to 4.8 for total length. The heritabilities for hypocotyl length (cm), germinated seeds (n hypocotyl), germinated seeds (% hypocotyl), root length (cm), germinated seeds (n roots), and germinated seeds (% roots) were moderate from 0.32 to 0.47. The heritability for root length was low with a value of 0.20. The most important positive and significant genetic correlations (0.80) were found between the hypocotyl length (cm) and root length, which means that the longer the hypocotyls, the longer the root. All variables studied have normal distribution, which is why they are considered quantitative inheritance. The results highlight lines that can be candidates for the registration of new drought-tolerant varieties or used as sources of drought tolerance in future common bean improvement programs. Our results indicate that multiple genetic factors are involved in the drought tolerance response of the F3.

Unveiling Genetic Basis Associated With Manganese Content in Turkish Common Bean (Phaseolus vulgaris L.) Germplasm Through a Genome‐Wide Association Study

ABSTRACTMicronutrient deficiencies, such as manganese (Mn), pose significant global health risks, affecting millions of people worldwide and leading to serious health conditions. Biofortifying crops, notably common beans, offer a sustainable solution to combat these deficiencies. This study aimed to uncover the genetic basis associated with Mn content in Turkish common bean (Phaseolus vulgaris) germplasm through a genome‐wide association study (GWAS), which is crucial for developing nutrient‐rich bean varieties. Here, we examined variation among 183 common bean accessions, collected from 19 provinces of Turkey and identified the genetic basis linked to seed Mn content. Genotype by environment interaction significantly influenced Mn content (p < 0.05). The mean Mn content was observed 31.69 mg kg−1 across the germplasm. Bingol‐16 had the lowest, while Malatya‐59 had the highest Mn contents. Stability analysis was performed using the ‘STABILITYSOFT’ method and found 10 stable accessions. The cluster constellation plot was generated using JMP statistical software. A total of 7900 DArTseq markers were used for association analysis, identifying 16 markers across four chromosomes (Pv2, Pv5, Pv7 and Pv11). Notably, markers DArT‐3374915 and DArT‐3375187 exhibited consistent associations across different environments, making them promising candidates for Mn‐focused breeding programmes. Gene annotation and interactome analysis, including BLAST searches and protein–protein interaction analysis, revealed associations of candidate genes with Mn concentration regulation, shedding light on potential mechanisms underlying Mn accumulation in common beans. Our findings lay a foundation for marker‐assisted breeding efforts in common bean improvement.

Comprehensive overview of host plant resistance and its progress in wilt resistance in castor bean (Ricinus communis L.)

Castor bean, a non-edible monotypic species known for its unique hydroxy fatty acid, is susceptible to a range of pathogens. Wilt caused by Fusarium oxysporum f. sp. ricini is the most complex and destructive disease. Chemical control of wilt has proven ineffective due to the systemic nature of the disease and the seed and soil borne nature of the pathogen. Physical, chemical, biological, and integrated management methods have shown only limited success in controlling wilt. Host plant resistance, however, stands out as the most promising strategy, offering a viable pathway for the genetic improvement of castor beans for wilt resistance. Screening techniques are well established, and several resistant donors have already been identified. While significant progress has been made in understanding the inheritance of wilt resistance, a complete understanding of its genetic mechanisms still requires further research. Single Nucleotide Polymorphism (SNP) markers and genomic regions linked to wilt resistance have been successfully identified. Reniform nematode (Rotylenchulus reniformis) has been identified as a predisposing factor for wilt, and genomic regions linked to nematode resistance have also been identified. However, Marker-assisted selection has not yet been utilized to develop wilt-resistant castor varieties. Further research is required to explore the pathogen diversity, host-pathogen interactions, and mechanisms underlying wilt resistance including the metabolites responsible for preventing the emergence of new pathogenic races and ensuring long-term protection against wilt.

Genome-wide characterization of PEBP genes in Mung bean (Vigna radiata L.) with functional analysis of VrFT1 in relation to photoperiod

Mung bean (Vigna radiata L.), a widely cultivated legume, belongs to the Fabaceae family’s Papilionoideae subfamily. Although Phosphatidylethanolamine-binding protein (PEBP) genes have been identified in several plant species, their presence and function in mung bean remain largely unexplored. In this study, we identified seven VrPEBP genes from mung bean and classified them into four clades: FT, MFT, TFL and FT-like. Cis-regulatory element analysis revealed that VrPEBP genes may play a role in light, hormone, and stress responses. Quantitative real-time PCR (qRT-PCR) analysis indicated that VrPEBPs were constitutively expressed in various tissues. However, tissue-specific expression patterns were observed among VrPEBP genes. Under short-day (SD) conditions, VrFT1 and VrMFT1 exhibited significantly higher expression levels than under long-day (LD) conditions at 8 and 4 h, respectively. Conversely, VrTFL2 and VrTFL3 showed significantly higher expression levels under LD conditions compared to SD conditions at 8 and 12 h, respectively. The varied expression patterns of these genes under different photoperiod suggest their potential involvement in the photoperiodic regulation of flowering in mung bean. Additionally, phenotypic analysis of transgenic Arabidopsis plants overexpressing VrFT1 revealed higher expression levels under SD conditions and predicted its role in promoting flowering. These results provide valuable insights into the evolution and function of PEBP genes in mung bean and lay the foundation for further research on their regulatory mechanisms and potential applications in mung bean improvement.

Interrelationship Between Emergence and Yield Parameters in Mung Bean: Implication for Selection

Abstract Rapid and uniform seed germination and seedling emergence have been associated with grain yield under diverse environmental conditions. Twenty-one (21) mung bean accessions were evaluated at Ile-Ife and Kishi out-stations of the Institute of Agricultural Research and Training (IAR & T), Nigeria, to identify the emergence parameter(s) that could be selected for improvement of mung bean for yield. The experiment was laid out in a randomized complete block design (RCBD) in three replications. Data were collected on emergence and yield parameters and analysed using the Statistical Analysis Software (SAS). Mean, heritability, and correlation coefficient were estimated. Path coefficient analysis was used to partition correlations into direct and indirect effects using seed yield as the dependent variable. Heritability estimate was moderate to high for most of the traits. Accessions 3, 6, 14 and 15 with high pod and seed yield had also high values of coefficient of velocity of emergence (CVE) and emergence percentage (E%). All emergence parameters except emergence energy had significant correlation with yield traits. CVE and Emergence Index (EI) had strong positive correlation with number of seeds.pod-1 and pod yield. When only the emergence parameters were considered, CVE had highest direct effect (0.74) on seed yield followed by E% (-0.73) and EI (0.70). Total indirect effects of EI and CVE accounted for only 6.06% and 11.9% of the total correlation, respectively. It therefore suggests that EI and CVE are emergence parameters that could be selected for at early stage in improvement of mung bean for yield.

Identification and Fine Mapping of a Mutant pv‐nts Gene Responsible for Dwarf and Thin Stem of Snap Bean (Phaseolus vulgaris L.)

ABSTRACTPlant height is one of the most important traits in the breeding of snap bean, which determines the planting density and the resistance to failure, which in turn affects its yield and quality. Therefore, studying the molecular mechanism of plant height in snap bean is an important measure to realize the improvement of snap bean. We obtained a dwarf, thin‐stemmed mutant nts (normal to slim) from a dwarf variety of snap bean A18 via 60CO‐γ‐ray treatment. We conducted phenotypic observations, endogenous hormone content measurements and genetic analyses of the dwarfing thin‐stemmed mutant nts and explored gene localization and candidate gene screening for the mutant trait in snap bean. Compared with wild‐type A18, nts mutant exhibited various abnormal phenotypes such as dwarfing, reduced branching, thinner top stem, reduced plant width, reduced number of leaf area and thousand grain weight and increased content of hormones such as indole‐3‐acetic acid (IAA) in the top stem. Genetic analysis indicated that the mutant trait was controlled by a single recessive nuclear gene, and the mutant gene was named pv‐nts. pv‐nts was localized to a 361.1‐kb segment on chromosome 8 as revealed by bovine serum albumin (BSA) hybrid pool sequencing and simple sequence repeat (SSR) molecular markers. Phvul.008G106300 (encoding LAX2 protein) was identified as a candidate gene corresponding to pv‐nts via gene function annotation. Phvul.008G106300 was significantly upregulated in nts mutant compared with wild‐type A18, which was consistent with the results of endogenous IAA levels. Sequence analysis showed that the Phvul.008G106300 gene in nts had a base mutation that altered the protein structure, thus causing the dwarfed, thin‐stemmed phenotype of cauliflower. Taken together, these results contribute to a better understanding of the genetic basis of dwarfing traits in snap bean.

Mapping of adult plant recessive resistance to anthracnose in Indian common bean landrace Baspa/KRC 8.

The common bean (Phaseolus vulgaris) has become the food of choice owing to its wealthy nutritional profile, leading to a considerable increase in its cultivation worldwide. However, anthracnose has been a major impediment to production and productivity, as elite bean cultivars are vulnerable to this disease. To overcome barriers in crop production, scientists worldwide are working towards enhancing the genetic diversity of crops. One way to achieve this is by introducing novel genes from related crops, including landraces like KRC 8. This particular landrace, found in the North Western Himalayan region, has shown adult plant resistance against anthracnose and also possesses a recessive resistance gene. In this study, a population of 179 F2:9 RIL individuals (Jawala ×KRC 8) was evaluated at both phenotypic and genotypic levels using over 830 diverse molecular markers to map the resistance gene present in KRC 8. We have successfully mapped a resistance gene to chromosome Pv01 using four SSR markers, namely IAC 238, IAC 235, IAC 259, and BM 146. The marker IAC 238 is closely linked to the gene with a distance of 0.29cM, while the other markers flank the recessive resistance gene at 10.87cM (IAC 259), 17.80cM (BM 146), and 25.22cM (IAC 235). Previously, a single recessive anthracnose resistance gene (co-8) has been reported in the common bean accession AB 136. However, when we performed PCR amplification with our tightly linked marker IAC 238, we got different amplicons in AB 136 and KRC 8. Interestingly, the susceptible cultivar Jawala produced the same amplicon as AB 136. This observation indicated that the recessive gene present in KRC 8 is different from co-8. As the gene is located far away from the Co-1 locus, we suggest naming the recessive gene co-Indb/co-19. Fine mapping of co-Indb in KRC 8 may provide new insights into the cloning and characterization of this recessive gene so that it can be incorporated into future bean improvement programs. Further, the tightly linked marker IAC 238 can be utilized in marker assisted introgression in future bean breeding programs. The novel co-Indb gene present in Himalayan landrace KRC 8, showing adult plant resistance against common bean anthracnose, is independent from all the resistance genes previously located on chromosome Pv01.

Screening for resistance of the common bean genotypes to common bacterial blight, and bean common mosaic virus

Common bacterial blight (CBB), and bean common mosaic (BCMV) limit common beans (Phaseolus vulgaris L.) production worldwide. This study was carried out to perform phenotypic screening and asses the leaf reaction of a resistant line to CBB and BCMV. The experiment was conducted using a Completely Randomized design with three replications under screen-house conditions. Four improved bean genotypes for bruchid resistance were collected from bean improvement projects at the Sokoine University of Agriculture and one commonly cultivated susceptible cultivar was collected from a local market. Bean seeds were sown in a pot with sterilized soil and Xap inoculated by spraying with a bacterial suspension at 18 days after planting, while mechanical inoculation was performed for BCMV on 10 days old leaves. Disease severity of CBB was assessed three times at 14, 21, and 35 days after inoculation using a 1-9 CIAT scale, while for BCMV, symptoms were assessed at 15 days after inoculation. Results show significant differences (p≤0.001) on resistance to both diseases among the common beans genotypes tested. 13A/59-98-3x3-3A (scored 1.3 for CBB; no infected plant with BCMV), AO 29-3-3A (scored 2.0 for CBB; no infected plant with BCMV) and KT020 (scored 1.3 for CBB; only 1 plant was infected with BCMV) had resistance to both diseases while BR59-63-10 was resistant to BCMV and intermediate resistance (scored 3.5) to CBB. Kablanketi was susceptible to both diseases (scored 8 for CBB; 2 plants infected with BCMV). This study verified the resistance against CBB and BCMV in three lines obtained from SUA used for breeding multiple disease resistant cultivars.

Exploring agro-morphological profiles of Phaseolus vulgaris germplasm shows manifest diversity and opportunities for genetic improvement

Common bean (Phaseolus vulgaris) is a seed crop with huge potential to contributing to food security in developing countries. In crop improvement, assessing genetic variability is a decisive step, requiring characterization of available crop germplasm. The present study aims at characterizing 39 common bean genotypes from various locations in Cameroon and five from Kenya using 19 qualitative and 36 quantitative traits of high descriptive values. Diversity among germplasm was assessed by determining diversity indices and carrying out multivariate analysis. Seventeen out of the nineteen qualitative traits (89.47%) were polymorphic, displaying each at least two phenotypic classes. High diversity was found. Average observed and expected number of phenotypic classes per trait were 3.74 and 2.53 respectively. Nei's genetic diversity value of 0.49 and Shannon-Weaver diversity index estimates of 0.74 were found. Significant differences were observed among genotypes for all measured quantitative traits. Yield traits showed significant correlation with other related quantitative traits. Cluster analysis separated the studied germplasm into three distinct groups, with the clustering pattern not showing any connection with location. The test of equality revealed significant difference between these clusters for most quantitative traits. Mahalanobis D2 statistics revealed germplasm of cluster I and III as potential parents for future breeding programs. This study identified genotypes with desirable agronomic traits such as higher number of seeds per pod, lower number of days to maturity, higher number of pods per plant, and higher yield. These and other important discriminatory traits are discussed and proposed for genetic improvement of common bean.

Diversity Assessment of Winged Bean [Psophocarpus tetragonolobus (L.) DC.] Accessions from IITA Genebank

The capability of winged bean to support food and nutrition security in sub-Saharan Africa is recurrently being affected by several constraints, which include a lack of genetic improvement. The dearth of adequate information on the level of available genetic diversity in winged bean germplasm has been a major setback in planning appropriate improvement programs. Fifteen winged bean accessions were assessed for genetic diversity using 10 quantitative traits and 10 simple sequence repeat (SSR) markers. The accessions were laid out in RCBD with three replicates for two growing seasons. Leaf samples were obtained from 10 plants representing each accession for SSR marker genotyping. The accessions exhibited significant (p < 0.05) differences for measured traits. Broad-sense heritability estimates varied from 10.31% for days to first plant maturity to 72.67% for pod weight. Pod weight had a positive and significant correlations with pod length (0.53, p < 0.05), pod width (0.70, p < 0.01), and number of seeds per pod (0.64, p < 0.01). However, the number of seeds per pod was negatively correlated with days to maturity (−0.71, p < 0.01). Number of seeds per pod was positively predicted by pod weight, seed thickness, and days to maturity. Cluster analysis delineated the accessions into two distinct groups. Average number of alleles of 4.2, gene diversity of 0.25, and polymorphic information content of 0.22 were recorded. Analysis of molecular variance revealed intra-accession variation of 95% as compared to inter-accession variation of 5%. Two primary genetic groups were identified and only three accessions, namely TPt-6, TPt-126, and TPt-48, showed genetic purity. The results of this study provide the basis for exploiting the existing diversity for winged bean improvement.

Whole-genome resequencing of common bean elite breeding lines

The expansion of bean genome technologies has prompted new perspectives on generating resources and knowledge essential to research and implementing biotechnological tools for the practical operations of plant breeding programs. This study aimed to resequence the entire genome (whole genome sequencing—WGS) of 40 bean genotypes selected based on their significance in breeding programs worldwide, with the objective of generating an extensive database for the identification of single nucleotide polymorphisms (SNPs). Over 6 million SNPs were identified, distributed across the 11 bean chromosomes. After quality variant filtering, 420,509 high-quality SNPs were established, with an average of 38,228 SNPs per chromosome. These variants were categorized based on their predicted effects, revealing that the majority exerted a modifier impact on non-coding genome regions (94.68%). Notably, a significant proportion of SNPs occurred in intergenic regions (62.89%) and at least one SNP was identified in 58.63% of the genes annotated in the bean genome. Of particular interest, 7841 SNPs were identified in 85% of the putative plant disease defense-related genes, presenting a valuable resource for crop breeding efforts. These findings provide a foundation for the development of innovative and broadly applicable technologies for the routine selection of superior genotypes in global bean improvement and germplasm characterization programs.

The chromosome-scale genome assembly of cluster bean provides molecular insight into edible gum (galactomannan) biosynthesis family genes

Cluster bean (Cyamopsis tetragonoloba (L.) Taub 2n = 14, is commonly known as Guar. Apart from being a vegetable crop, it is an abundant source of a natural hetero-polysaccharide called guar gum or galactomannan. Here, we are reporting a chromosome-scale reference genome assembly of a popular cluster bean cultivar RGC-936, by combining sequencing data from Illumina, 10X Genomics, Oxford Nanopore technologies. An initial assembly of 1580 scaffolds with an N50 value of 7.12 Mb was generated and these scaffolds were anchored to a high density SNP linkage map. Finally, a genome assembly of 550.31 Mb (94% of the estimated genome size of ~ 580 Mb (through flow cytometry) with 58 scaffolds was obtained, including 7 super scaffolds with a very high N50 value of 78.27 Mb. Phylogenetic analysis using single copy orthologs among 12 angiosperms showed that cluster bean shared a common ancestor with other legumes 80.6 MYA. No evidence of recent whole genome duplication event in cluster bean was found in our analysis. Further comparative transcriptomics analyses revealed pod-specific up-regulation of genes encoding enzymes involved in galactomannan biosynthesis. The high-quality chromosome-scale cluster bean genome assembly will facilitate understanding of the molecular basis of galactomannan biosynthesis and aid in genomics-assisted improvement of cluster bean.

Genetic variation in a tepary bean (Phaseolus acutifolius A. Gray) diversity panel reveals loci associated with biotic stress resistance.

Tepary bean (Phaseolus acutifolius A. Gray), indigenous to the arid climates of northern Mexico and the Southwest United States, diverged from common bean (Phaseolus vulgaris L.), approximately 2 million years ago and exhibits a wide range of resistance to biotic stressors. The tepary genome is highly syntenic to the common bean genome providing a foundation for discovery and breeding of agronomic traits between these two crop species. Although a limited number of adaptive traits from tepary bean have been introgressed into common bean, hybridization barriers between these two species required the development of bridging lines to alleviate this barrier. Thus, to fully utilize the extant tepary bean germplasm as both a crop and as a donor of adaptive traits, we developed a diversity panel of 422 cultivated, weedy, and wild tepary bean accessions which were then genotyped and phenotyped to enable population genetic analyses and genome-wide association studies for their response to a range of biotic stressors. Population structure analyses of the panel revealed eight subpopulations and the differentiation of botanical varieties within P. acutifolius. Genome-wide association studies revealed loci and candidate genes underlying biotic stress resistance including quantitative trait loci for resistance to weevils, common bacterial blight, Fusarium wilt, and bean common mosaic necrosis virus that can be harnessed not only for tepary bean but also common bean improvement.

Genetic Diversity Assessment of Winged Bean [Psophocarpus tetragonolobus (L.) DC.] Accessions Using Agronomic and Seed Morphometric Traits

Winged bean [Psophocarpus tetragonolobus (L.) DC.] is an underutilized legume with the potential to contribute to nutrition and food security globally, particularly in sub-Saharan Africa (SSA). However, more attention needs to be paid to exploiting its full potential due to a lack of adequate knowledge of the existing genetic diversity in the available winged bean germplasm. To bridge this gap, thirty accessions of winged beans sourced from the Gene Bank of the International Institute of Tropical Agriculture (IITA), Ibadan, were evaluated for seed morphometric and selected agro-morphological traits at three agro-ecological zones in Nigeria. The data obtained were subjected to analysis of variance (ANOVA), principal component (PC) analysis, cluster analysis, and correlation analysis. Significant differences (p < 0.05) were observed among the accessions for all measured traits. The first two PCs accounted for 88.2% of the variation observed among the accessions for all measured traits. Accessions were grouped into three clusters based on the agro-morphological traits and three clusters under the multi-spectral imaging (MSI) system. TPt-31 had the highest seed yield per plant, pod weight per plant, and early maturity, while TPt-7 had an extended flowering and maturity period, the highest number of pods per peduncle and pods per plant, as well as the lowest seed yield. These accessions could be a good resource for future winged bean improvement programs. The result also confirmed that the MSI system is an invaluable tool for discriminating among accessions of the same crop species. The findings of this study provide insight into the genetic diversity of winged bean germplasm, which could contribute to improving its yield and quality in SSA and globally.

Prevalence and Host Resistance to Common Bean Rust Disease in Western and Central Kenya

Rust, caused by Uromyces appendiculatus (Pers.) Unger, is among the most devastating diseases of the common bean (Phaseolus vulgaris L.) worldwide. The pathogen is highly genetically variable, causing severe epidemics under favourable weather conditions. The objectives of this study were to determine the distribution of bean rust in major production areas in Kenya and identify potential sources of resistance for breeding. A field survey was conducted in five counties targeting smallholder common bean farmers in western and central Kenya, where data on the incidence and severity of bean rust and crop management practices by farmers were recorded. Additionally, seeds of the evaluated genotypes were collected from farms visited for further testing. A total of 77 common bean genotypes were subjected to natural infection under field conditions and inoculated with races 29–1, 29–3, 61–1, and 63–1 of rust under greenhouse conditions at the University of Embu. The gene pool affiliation of the genotypes was determined through the phaseolin protein marker analysis. Rust incidence and severity data were subjected to an analysis of variance using GenStat statistical software. The results showed that bean rust occurred in all counties although there were significant differences ( P < 0.001 ) in incidence and severity among the surveyed localities. Based on a 1–9 severity rating scale, Bungoma County recorded the highest mean severity of 3.99 and an incidence of 71%. Cultivar grown, use of fungicides, management of residues, and crop spacing had a significant effect on bean rust severity. Under field and greenhouse conditions, the genotypes revealed high variations in response to rust, with 71% of the genotypes being susceptible under greenhouse inoculations. Enclave, MU#13, UN2-Darkgreen, UN6-Nakholo, Kat X56, and KMR-11 genotypes were identified as resistant and can be used as prospective parents in common bean improvement programs in Kenya. This study revealed high occurrence and distribution of common bean rust and thus provides critical baseline information for common bean rust management in Kenya.

High yielding common bean (Phaseolus vulgaris L.) varieties 'NIFA Lobia Red-22 and NIFA Lobia Yellow-22

Common bean (Phaseolus vulgaris L.) improvement program was initiated at Nuclear Institute for Food and Agriculture (NIFA) in 2018. Germplasm from various research institutes and farmers’ fields in KP was collected. The collected germplasm was evaluated in non-replicated fashion in spring 2018 and 2019 at research farm of NIFA for plant type, yield and yield components. Six genotypes were finally selected based on seed color, growth habit and subsequently tested in replicated yield trials conducted at NIFA, Peshawar and on farmers’ fields at Charsadda in spring 2020 & 2021, at Agricultural Research Institute (ARI), Mingora, Swat and Agricultural Research Station (ARS), Chitral in Kharif 2020, and on farmers’ fields at different locations in Kuram in kharif 2020 and 2021. Two genotypes, NCB-Tajaki (NIFA Lobia Red-22) and NCB-Watani (NIFA Lobia Yellow-22) out yielded all other genotypes across all locations as well as seasons. In spring 2020 and 2021, NCB-Tajaki (NIFA Lobia Red-22) and NCB-Watani (NIFA Lobia Yellow-22) produced higher average seed yield of 2195 and 2206 kg ha-1, respectively, whereas in kharif 2020 and 2021, the two genotypes produced higher average seed yield of 2082 and 2075 kg ha-1, respectively compared with other genotypes. The two genotypes were approved by the KP Seed Council under the name NIFA Lobia Red-22 and NIFA Lobia Yellow-22 for general cultivation in common bean growing areas of the KP on 20-01-2022.

Genotype – genotype × environment (GGE) biplot analysis of winged bean for grain yield

Abstract The winged bean is an underutilized legume that is adapted to the tropics. It has good prospects as a significant multi-purpose food crop including human nutrition, cattle feed, and environmental protection. However, little research attention has been given to the crop to address the identified constraints, especially low yield in Nigeria. To improve its yield potential, GGE biplot analysis was used to identify high-yielding and stable winged bean genotypes, previously collected from the continent of Asia, and Nigeria for yield improvement. Twenty winged bean genotypes were being evaluated under the rainfed condition at three locations (Ibadan, Ile-Ife, and Kishi) for two years, comprising six environments. The obtained results showed that the seed yield (SY) ranged from 805.61 kg.ha−1 (Ibadan) to 1,096.35 kg.ha−1 (Kishi), with SY of 988.42 kg.ha−1 across the locations. The winged bean reached its first flowering, 50% flowering, 50% podding, and 70% physiological maturity in 74, 80, 93, and 137 days after being planted, respectively across the locations. The GGE biplot analysis showed that the principal component (PC) axes captured 71.5% of the total variation, where PC1 and PC2 were responsible for 36.6% and 34.9%, respectively. Genotype, environment, and their interaction had a significant effect on SY. Environments IB20 and IF20 were adjudged the most ideal environments to discriminate between the genotypes. Genotype Tpt-12 was identified as high-yielding and stable. Tpt-12 would be recommended for commercial farming in southwestern Nigeria. The selected high-yielding winged bean genotypes are hereby recommended as promising parental lines for the grain yield improvement in the winged bean improvement programs.

Elite Lines of Common Bean (Phaseolus vulgaris L.) are Showing Diversity for Yield Promoting Traits

Twelve elite lines of common bean were evaluated to identify diversity for morphological traits under rainfed conditions of Rawalakot, Azad Kashmir. The elite lines were found statistically different for the parameters under study. The elite line G-3990 produced highest grain yield per plant (23.45g) while lowest yield was recorded in NKB-1 (0.871g). G-3990 could be released as a variety in the mountainous regions for example in Azad Kashmir. Cluster analysis based on metric traits showed that the elite lines G-4258 and G-3661 having moderate grain yield per plant and 100-seed weight were grouped in same cluster. These lines could be utilized for the common bean improvement programme through breeding and hybridization. High heritability and genetic advance was estimated for 100-seed weight which indicated preponderance of additive genetic effects. For grain yield per plant, days to maturity and days to flowering the heritability estimates were moderate. It indicated a possible involvement of non-additive genes in their regulation.

Fine mapping and characterisation of a PV-PUR mediating anthocyanin synthesis in snap bean (Phaseolus vulgaris L.).

The online version contains supplementary material available at 10.1007/s11032-023-01362-8.