Common Bean Phaseolus Vulgaris Research Articles

The outstanding diversity of rhizobia microsymbionts of common bean (Phaseolus vulgaris L.) in Mato Grosso do Sul, central-western Brazil, revealing new Rhizobium species.

Common bean is considered a legume of great socioeconomic importance, capable of establishing symbioses with a wide variety of rhizobial species. However, the legume has also been recognized for its low efficiency in fixing atmospheric nitrogen. Brazil is a hotspot of biodiversity, and in a previous study, we identified 13 strains isolated from common bean (Phaseolus vulgaris) nodules in three biomes of Mato Grosso do Sul state, central-western Brazil, that might represent new phylogenetic groups, deserving further polyphasic characterization. The phylogenetic tree of the 16S rRNA gene split the 13 strains into two large clades, seven in the R. etli and six in the R. tropici clade. The MLSA with four housekeeping genes (glnII, gyrB, recA, and rpoA) confirmed the phylogenetic allocation. Genomic comparisons indicated eight strains in five putative new species and the remaining five as R. phaseoli. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) comparing the putative new species and the closest neighbors ranged from 81.84 to 92.50% and 24.0 to 50.7%, respectively. Other phenotypic, genotypic, and symbiotic features were evaluated. Interestingly, some strains of both R. etli and R. tropici clades lost their nodulation capacity. The data support the description of the new species Rhizobium cerradonense sp. nov. (CNPSo 3464T), Rhizobium atlanticum sp. nov. (CNPSo 3490T), Rhizobium aureum sp. nov. (CNPSo 3968T), Rhizobium pantanalense sp. nov. (CNPSo 4039T), and Rhizobium centroccidentale sp. nov. (CNPSo 4062T).

Exploring I, bc-12 and bc-3 Gene Locus in Promising Common Bean Lines

Common beans (Phaseolus vulgaris L.), known as the "poor man's meat", is an internationally important legume crop that appeals to farmers as well as consumers. Many biotic stressors such as bean common mosaic virus (BCMV), bean common mosaic necrosis virus (BCMNV) cause significant yield and quality losses in common bean. The most efficient and cost-effective way to lessen of these factors is to develop resistant cultivars. Local genotypes have been cultivated in many areas for years and have varied distinguishing characteristics as a result of spontaneous mutations. Identifying bean germplasm harboring gene sources is critical for developing resistant cultivars against BCMV and BCMNV. For this purpose, a total of 43 promising common bean lines selected from local genotypes cultivated across various regions of Türkiye were subjected to screening using diverse molecular markers (ROC11, SBD-5 and SW-13) to investigate gene sources associated with BCMV and BCMNV. The findings revealed that 21 lines had both I and bc-12 gene locus. In addition, the bc-12+bc-3 gene loci were discovered to be present in the 8 common bean lines. The combination of I+bc-3 resistance genes, which guarantees immune reaction to BCMV and BCMNV, was found in only one line; YLV-32. These gene sources can be evaluated in marker-assisted breeding to develop modern cultivars resistant to BCMV and BCMNV by breeders.

Association of cropping practices, cropping areas, and foliar diseases of common bean (Phaseolus vulgaris L.) in Ethiopia

Common bean production is being constrained by a number of diseases. The survey was carried out to prioritize common bean diseases and their associations with cropping areas and cultural practices. A stratified random assessment on 114 farmer's fields was conducted in Ethiopia's four common bean producing zones (Metekel, Sidama, Wolaita, and Halaba). Data are collected randomly on disease severity, incidence levels, and agronomic practices. The results revealed that eleven foliar diseases were found to affect common bean production. Among them, the maximum disease severity and distribution was scored for angular leaf spot (Pseudocercospora griseola) (mean disease severity of 17.8%) and bean anthracnose (Colletotrichum lindemuthianum) (10.9%) followed by floury leaf spot (Mycovellosiella phaseoli), ascochyta blight (Ascochyta phaseolorum Sacc), and web blight (Thanatephorus cucumeris). A multiple correspondence analysis was conducted, and revealed a significant association between the diseases, cropping areas and cultural practices. Optimal crop density was found to be associated with lower bean anthracnose and mosaic virus severities, while being liked to high levels of angular leaf spot and frog-eye leaf spot. Additionally, optimum sowing dates were associated with low severities of bean anthracnose, angular leaf spot, frog-eye leaf spot, Halo Blight, and mosaic virus. On the other hand, a high weediness level was found to be associated with higher levels of web blight and bean anthracnose. Intercropping and row planting were obtained to reduce angular leaf spot and increase occurance of ascochyta blight compared to monocropping. Furthermore, row planting were found to decrease bean anthracnose, angular leaf spot, and cercospora leaf spot when compared to broadcasting. The application of fertilizer was found to decrease the occurances of bean anthracnose, halo blight, floury leaf spot, and angular leaf spot. Therefore, efforts should focus on the optimization and integration of cultural practices for managing disease and producing common bean sustainably.

Fibrinolytic Protease Activity of Crude Enzyme from Fermented Sunflower (Helianthus annuus) and Common Bean (Phaseolus vulgaris) seeds by Rhizopus microsporus var. oligosporus FNCC 6010 in Solid State Fermentation

In the entire world, cardiovascular diseases (CVDs) are the main cause of death. For the treatment of CVDs, microbial fibrinolytic enzymes are highly regarded as novel therapeutic candidates. This study was purposed to determine the fibrinolytic protease activity produced by fungus source, which is Rhizopus microsporus var. oligosporus FNCC 6010 in fermented sunflower (Helianthus annuus) seed and common bean (Phaseolus vulgaris) seed. Fermentation was carried out by solid-state fermentation method at an initial pH of 5, incubation temperature of 33±1°C, and incubation time of 24 hours. The fermented seed was extracted to obtain supernatant as the crude enzyme. The proteolytic activity assay was done by the skimmed milk agar (SMA) plate method to obtain the proteolytic index, and the fibrinolytic activity assay was conducted by the fibrin-agarose plate method to get the fibrinolytic index. The results show that crude enzymes from fermented H. annuus and P. vulgaris seeds by R. microsporus have fibrinolytic protease activity with proteolytic index 2.64 ± 0.01 and 2.23 ± 0.04, respectively. The fibrinolytic index is 2.40 ± 0.06 and 1.64 ± 0.06, respectively. Therefore, the crude enzyme has the potential to be further researched as a candidate for thrombolytic agents. The purification, characterization, and in-depth research are needed to develop enzymes into preparations for preventing and treating CVDs.

Genome-wide analysis of the SMXL gene family in common bean and identification of karrikin-responsive PvSMXL2 as a negative regulator of PEG-induced drought stress

Common bean (Phaseolus vulgaris L.) is a major legume crop worldwide, but its growth and development frequently face challenges due to abiotic stresses, particularly drought. Proper supplement of copper could mitigate the adverse effects of drought, but excessive accumulation of this metal in plants can be harmful. The suppressor of MAX2 1-like (SMXL) gene family, which plays important roles in various plant processes, including stress responses, remains poorly understood in common bean. In this study, we identified nine orthologues of SMXL genes in common bean, which are located on six chromosomes and classified into four subgroups. Basic molecular properties, including theoretical isoelectric point (PI), molecular weight (MW), grand average of hydropathicity (GVIO), gene structure, and conserved motifs were characterized, and numerous cis-elements in promoters were predicted. The expression patterns of PvSMXL genes were found to be distinct under 10% polyethylene glycol (PEG)-induced drought stress and 200 μM Cu treatments. Most PvSMXLs showed reduced expression in response to Cu treatment, whereas nearly half PvSMXLs exhibited inducible expression under drought stress. PvSMXL2, which exhibited a rapid response to karrikin 1 (KAR1), an active form of the plant growth regulators newly found in the smoke of burning plant material, was down-regulated by both PEG-induced drought and Cu stresses. Transient silencing of PvSMXL2 resulted in enhanced drought stress tolerance without conferring Cu tolerance. These findings provide valuable insights into the functions of SMXL genes in common bean under abiotic stress conditions.

Race Structure and Molecular Diversity of Colletotrichum lindemuthianum of Common Bean in Zambia.

Anthracnose, caused by the fungus Colletotrichum lindemuthianum, is a major disease of common bean (Phaseolus vulgaris L.) worldwide. C. lindemuthianum is genetically highly variable, and understanding the pathogen's diversity and distribution is a key step in developing common bean varieties with durable anthracnose resistance. The objectives of this study were to (i) characterize the race structure of C. lindemuthianum in Zambia and (ii) assess the molecular diversity of C. lindemuthianum in Zambia. A field survey was conducted in 20 bean-growing districts in Zambia to collect anthracnose symptomatic bean plants. A total of 103 C. lindemuthianum isolates were collected and characterized based on their reactions on 12 common bean race differential cultivars. RAM and ERIC-BOX DNA markers were used to assess molecular diversity of 60 isolates. A total of 58 races were characterized from the 103 isolates. Race 5 was the least virulent, and race 1631 was the most virulent based on their reaction on the 12 race differential cultivars. Race 19 had the highest recovery frequency (11%) and was the most extensively dispersed among the 22 bean-growing districts from where the isolates were collected. Only six races had previously been reported in Zambia, and 52 races were identified as new races reported for the first time in Zambia. Two races were virulent only on Andean cultivars, 11 races were virulent only on Middle American cultivars, and 45 races were virulent on both Andean and Middle American cultivars. No individual isolate showed pathogenicity on all the differential cultivars, and no isolate overcame the Co-4, Co-5, and Co-7 resistance gene pyramid that naturally exists in G2333. Phylogenetic analysis categorized the 60 isolates in six major clusters and six subclusters. The 60 isolates showed high genetic heterogeneity among and within a race of the same virulence. The study has revealed the existence of both Andean and Middle American races and extensive molecular diversity of C. lindemuthianum in Zambia. The knowledge on the race structure of C. lindemuthianum that this study has provided will be valuable for making breeding decisions on the host plant resistance genes required for developing common bean varieties with durable resistance to anthracnose in Zambia.

Effect of Phosphorus Fertilizer and Seed Rates on Growth and Yield of Common Bean (Phaseolus Vulgaris L) in Kunduz, Afghanistan

A field experiment was conducted on the Effect of phosphorus fertilizer and seed rates on the growth and yield of common bean (Phaseolus vulgaris L) at the Farm of the agriculture faculty of Kunduz University during the spring season of 2023 to determine the optimum rates of phosphorus fertilizer and seed rates for maximum yield of common bean in the northeast of Afghanistan (Kunduz province). The treatment consists of three phosphorus levels (0kgP2O5ha-1, 40kgP2O5ha-1 and 80kgP2O5ha-1) and four combined seed rates (125 kgha-1, 150 kgha-1, 175 kgha-1 and 200 kg ha-1) laid out in randomized complete block design (RCBD) with three replications. The results revealed that phosphorus levels and different seed rates significantly affected on growth, yield attributes and yield of common bean on plant height, Leaf area/plant (cm2), Brunches/plant, Root dry weight/plant(g), Nodules/pant, No. of notes/plant, Pods/plant, Seeds/pod, 100 seed weight, seed yield/plant(g) and Grain Yield t/ha, the highest plant height (44.10cm), Leaf area/plant (217.18cm2), Brunches/plant(11.75), Root dry weight/plant (2.282g), Nodules/pant (12.16), Leaves/plant (47.833), No. of notes/plant (7.88), Pods/plant (16.98), Seeds/pod (6.97), 100 seed weight(34.536), seed yield/plant(8.83g) and Grain Yield (2.20t/ha) was in treatments 80kgP2O5ha-1 respectively. Seed rates were also significantly affected in treatment 200 kg ha-1 except for harvest index; all other yield attributes and yield was significant; the highest yield attributes and yield was in seed rate 200 kg ha-1. Thus 80kgP2O5ha-1with 200 kg ha-1 was found to be the best combination under northeast of Afghanistan agro-ecology as it gave higher values for yield and most yield related traits.

The Key Physiological and Biochemical Traits Underlying Common Bean (Phaseolus vulgaris L.) Response to Iron Deficiency, and Related Interrelationships

Iron deficiency is a worldwide nutritional problem affecting crop production. In Tunisia, this mineral disorder hampers the growth and yield of the major crops due to the abundance of calcareous soils that limit iron availability. The common bean is one of these crops suffering from lime-induced iron chlorosis. The exploration of the variability of common bean responses to iron deficiency allows us to screen tolerant cultivars and identify useful traits and indicators for further screening programs. To this end, two common bean cultivars (coco blanc, CB, and coco nain, CN) were cultivated hydroponically in standard nutrient solution (control) or nutrient solution deprived of iron (stressed). Analyses were reported on plant growth, photosynthetic pigments, photosynthesis, iron distribution, H-ATPase, and Fe-chelate reductase (Fe-CR) activities; important indicators were calculated; and convenient correlations were established. Current results demonstrated that iron deficiency stimulated specific symptoms of iron chlorosis on young leaves that were more precocious and severe in CB than CN. Spad index and chlorophyll pigments measurement confirmed these morphological changes and cultivar differences. Net photosynthesis (Pn) showed the same scheme of variation, with a significant decrease in Pn while respecting the previous cultivar’s variability. Plant growth is no exception to this general trend. The biomass decrease was two times higher in CB than CN. Otherwise, this mineral disorder significantly decreased Fe concentration in all plant organs. However, CN accumulated 40% more Fe than CB, resulting from its higher Fe Fe-CR and H-ATPase activities. Our results also demonstrated the close dependence of these metabolic functions on Fe availability in shoots and the strict relationship between Fe-CR and H-ATPase, photosynthesis, and chlorophyll content. Otherwise, CN demonstrated higher efficiency of Fe’s use (FeUE) for the key metabolic functions (photosynthesis, chlorophyll biosynthesis, and plant growth). The relative tolerance of CN as compared to CB was explained by its ability to establish a functional system less vulnerable to iron deficiency that operates effectively under problematic conditions. This system involves metabolic functions in shoots (photosynthesis, chlorophyll biosynthesis, Fe repartition, etc.) and others in roots (H-ATPase, Fe-CR), which are strictly interdependent.

Mixture of winter cover crops improves soil physical properties under no-tillage system in a subtropical environment

The monocrop of winter cover crops is a common practice under no-tillage system (NTS) in subtropical environment but increase diversity of cover crop species can be an alternative to improve soil physical quality, with positive effects on crop production. This study evaluated whether using a greater diversity of cover crop species affects soil physical properties, as well as grain yield of soybean (Glycine max L.) and common bean (Phaseolus vulgaris L.) under NTS in three growing seasons. The experimental design was in randomized blocks with four replications. The treatments were monocrop of black oat (Avena strigosa Schreb.); intercropping of black oat and turnip (Brassica napus L.); and a mixture of black oat, turnip, white oat (Avena sativa L.), rye (Secale cereale L.), white lupine (Lupinus albus L.), and common vetch (Vicia sativa L.). Cover crop biomass yield, soil physical properties, and grain yield of summer crops were evaluated. Using a mixture of cover crops improved soil physical properties by decreasing soil bulk density up to 5 %, increasing soil air-filled porosity at –100 hPa (0.0–0.2 m) up to 27 % and saturated hydraulic conductivity (0.0–0.2 m) up to 300 %. Common bean grain yield and 1000-grain weight in succession to the mixture of cover crops increased by 15 % and 4 %, respectively. Soybean yield components were not affected by treatments. The increased diversity of winter cover crops improved soil physical properties in relation to monocrop in NTS, as well as improved crop yield of common bean, which is a shallower root growth specie, more sensitive to soil constraints.

Identification and characterization of Phaseolusvulgaris endornavirus 1, 2 and 3 in common bean cultivars of East Africa

Persistent viruses include members of the family Endornavirus that cause no apparent disease and are transmitted exclusively via seed or pollen. It is speculated that these RNA viruses may be mutualists that enhance plant resilience to biotic and abiotic stresses. Using reverse transcription coupled polymerase chain reactions, we investigated if common bean (Phaseolus vulgaris L.) varieties popular in east Africa were hosts for Phaseolusvulgaris endornavirus (PvEV) 1, 2 or 3. Out of 26 bean varieties examined, four were infected with PvEV1, three were infected with both PvEV1 and PvEV2 and three had infections of all three (PvEV) 1, 2 and 3. Notably, this was the first identification of PvEV3 in common bean from Africa. Using high-throughput sequencing of two east African bean varieties (KK022 and KK072), we confirmed the presence of these viruses and generated their genomes. Intra- and inter-species sequence comparisons of these genomes with comparator sequences from GenBank revealed clear species demarcation. In addition, phylogenetic analyses based on sequences generated from the helicase domains showed that geographical distribution does not correlate to genetic relatedness or the occurrence of endornaviruses. These findings are an important first step towards future investigations to determine if these viruses engender positive effects in common bean, a vital crop in east Africa.

Identification, Evolutionary Relationship Analysis of the Trehalose-6-Phosphate Synthase (TPS) Gene Family in Common Bean (Phaseolus vulgaris) and Their Expression in Response to Cold Stress

Identification, Evolutionary Relationship Analysis of the Trehalose-6-Phosphate Synthase (TPS) Gene Family in Common Bean (Phaseolus vulgaris) and Their Expression in Response to Cold Stress

Linked candidate genes of different functions for white mold resistance in common bean (Phaseolus vulgaris L) are identified by multiple QTL mapping approaches.

White mold (WM) is a major disease in common bean (Phaseolus vulgaris L.), and its complex quantitative genetic control limits the development of WM resistant cultivars. WM2.2, one of the nine meta-QTL with a major effect on WM tolerance, explains up to 35% of the phenotypic variation and was previously mapped to a large genomic interval on Pv02. Our objective was to narrow the interval of this QTL using combined approach of classic QTL mapping and QTL-based bulk segregant analysis (BSA), and confirming those results with Khufu de novo QTL-seq. The phenotypic and genotypic data from two RIL populations, 'Raven'/I9365-31 (R31) and 'AN-37'/PS02-029C-20 (Z0726-9), were used to select resistant and susceptible lines to generate subpopulations for bulk DNA sequencing. The QTL physical interval was determined by considering overlapping interval of the identified QTL or peak region in both populations by three independent QTL mapping analyses. Our findings revealed that meta-QTL WM2.2 consists of three regions, WM2.2a (4.27-5.76 Mb; euchromatic), WM 2.2b (12.19 to 17.61 Mb; heterochromatic), and WM2.2c (23.01-25.74 Mb; heterochromatic) found in both populations. Gene models encoding for gibberellin 2-oxidase 8, pentatricopeptide repeat, and heat-shock proteins are the likely candidate genes associated with WM2.2a resistance. A TIR-NBS-LRR class of disease resistance protein (Phvul.002G09200) and LRR domain containing family proteins are potential candidate genes associated with WM2.2b resistance. Nine gene models encoding disease resistance protein [pathogenesis-related thaumatin superfamily protein and disease resistance-responsive (dirigent-like protein) family protein etc] found within the WM2.2c QTL interval are putative candidate genes. WM2.2a region is most likely associated with avoidance mechanisms while WM2.2b and WM2.2c regions trigger physiological resistance based on putative candidate genes.

GmBBM7 promotes callus and root growth during somatic embryogenesis of soybean (Glycine max)

The BABY BOOM (BBM) subfamily of the AP2/ERF transcription factor family is the main regulator of totipotency in plant cells and plays an important role in regulating cell proliferation and plant growth and development. Previously, we identified GmBBM7, a key gene of the soybean BBM gene subfamily (GmBBM family). In this study, we aimed to analyze its molecular characteristics and role in somatic embryogenesis in soybean. First, we identified 17 members of GmBBM family. Phylogenetic and collinear analyses revealed that the GmBBM family genes mainly exhibited a strong genetic relationship with the those of PvBBM family, the BBM family of common bean (Phaseolus vulgaris). Analysis of the promoters revealed that GmBBM family genes were mainly regulated by plant hormones. The expression of GmBBM7 varied in various tissues of soybean. Particularly, it was higher in the roots, immature embryos, grains and callus. Subcellular localization analysis indicated that GmBBM7 encodes a nuclear protein. Furthermore, overexpressed GmBBM7 could significantly enhance callus formation by regulating the levels of gibberellin A1, A3 and A7; abscisic acid; and salicylic acid and could promote root growth and development. In summary, GmBBM7 is an important regulatory gene for somatic embryogenesis and root elongation in soybean. GmBBM7 overexpression in soybean could increase the callus formation rate and density through hormonal pathways and could increase root growth. This study provided theoretical basis for efficient breeding of soybean via gene editing, transgenic and other techniques.

Boundary line analysis and machine learning models to identify critical soil values for major crops in Guatemala

AbstractAccurate and economically sound soil fertility recommendations are critical for ensuring profitable food production for smallholder farmers. However, such recommendations are lacking in many areas due to insufficient soil and crop response data. This study was conducted between 2016 and 2022 using boundary line analysis to evaluate crop response to soil fertility on 644 farms in Guatemala. We identify optimal soil property conditions for maize (Zea mays L.), common bean (Phaseolus vulgaris L.), and coffee (Coffea arabica L.) production in Guatemala and use crop price information to develop economically sound fertilization recommendations. We also analyzed the drivers of yield outcomes and assessed their relative importance with machine learning (ML) models. Results demonstrate that a majority of country‐level data currently have sub‐optimal soil nutrient levels and by optimizing nutrients, yields and profits could be improved in 64%, 51%, and 69% of maize, common bean, and coffee crops, respectively. In addition, ML underscored the central role of climate in shaping yield outcomes. Variable importance rankings from random forest indicated climate and water balance variables increased predictive accuracy more than soil parameters, highlighting the critical need for climate‐smart adaptations in the region. The pairing of boundary line with ML analysis provided unique and complementary information about factors that drive yield of major crops in Guatemala. This is an effective approach for developing fertility recommendations in Guatemala and could be replicated in other countries where critical nutrient recommendations are currently lacking for closing yield gaps and identifying yield response to climatic stochasticity.

Comparative transcriptome analysis of two varieties of common bean (Phaseolus vulgaris L.) to identify candidate drought resistance genes

In this work, we studied the physiological, biochemical and molecular mechanisms underlying the response to polyethylene glycol (PEG) in a drought-resistant variety ‘HZYTJ’ and the sensitive variety ‘WZWJD’ of common beans. The two bean varieties were subjected to a 10% PEG simulated drought stress treatment, and the resultant physiological and biochemical characteristics of the leaves and roots were compared. The superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and other indicators were higher in ‘HZYTJ’ than in ‘WZWJD’; additionally, the ‘HZYTJ’ exhibited slower changes in response to stress. The proline content in ‘HZYTJ’ changed slowly compared to that in ‘WZWJD’. The transcriptome analysis of the two varieties showed that 1,361 and 1,447 genes were differentially expressed in ‘HZYTJ’ and ‘WZWJD’, respectively. DEGs were also analyzed via the KEGG pathway database, and 10 significant metabolic pathways were found to be involved in ‘HZYTJ’, while nine were found in ‘WZWJD’. Using the GO function database, we found that 111 significant GO terms were involved in ‘HZYTJ’, whereas 125 were involved in ‘WZWJD’. Through analysis of transcription factors, 487 DEGs were identified, of which bHLH transcription factors were the most abundant, followed by ERF, MYB-related, B3 and other transcription factor families. The selected and screened genes with DEGs were validated by qRT–PCR. These results provide a basis for further research into the drought resistance of the common bean.

A robust SNP-haplotype assay for Bct gene region conferring resistance to beet curly top virus in common bean (Phaseolus vulgaris L.).

Beet curly top virus (BCTV), which is synonymous with curly top virus (CTV), causes significant yield loss in common bean (snap and dry beans) cultivars and several other important crops. Common bean cultivars have been found to be resistant to CTV, but screening for resistance is challenging due to the cyclical nature of epidemics and spotty feeding by the leafhopper that vectors the virus. We used an SNP dataset for the Snap Bean Association Panel (SnAP) agro-inoculated with CTV-Logan (CA/Logan) strain to locate the Bct gene region to a 1.7-Mb interval on chromosome Pv07 using genome-wide association study (GWAS) analysis. Recombinant lines from the SnAP were used to further narrow the Bct region to a 58.0-kb interval. A missense SNP (S07_2970381) in candidate gene Phvul.007G036300 Exonuclease V (EXO5) was identified as the most likely causal mutation, and it was the most significant SNP detected by GWAS in a dry bean population (DBP) naturally infected by the CTV-Worland (Wor) strain. Tm-shift assay markers developed for SNP S07_2970381 and two linked SNPs, S07_2970276 and S07_2966197, were useful for tracking different origins of the Bct EXO5 candidate gene resistance to CTV in common bean. The three SNPs identified four haplotypes, with haplotype 3-1 (Haplo3-1) of Middle American origin associated with the highest levels of CTV resistance. This SNP-haplotype assay will enable breeders to track resistance sources and to develop cultivars with better CTV resistance.

Characterization of resistance to angular leaf spot of common bean (Phaseolus vulgaris L.) breeding line SPS50HB

AbstractThe common bean (Phaseolus vulgaris L.) makes an important contribution to the human diet, particularly in Africa and Latin America. Because angular leaf spot (ALS), caused by the fungal pathogen Pseudocercospora griseola, is one of the most severe foliar diseases of the bean plant, an important priority is to identify genes encoding resistance. The present study focused on the resistance shown by the Mesoamerican common bean breeding line SPS50HB. From the pattern of segregation for resistance displayed in an F2 population bred from a cross between SPS50HB and the ALS‐susceptible Ethiopian variety Red Wolaita, it was concluded that the resistance of SPS50HB is controlled by two unlinked dominant genes. An allelism test indicated that one of these genes was either identical with, allelic to, or closely linked to the major gene Phg‐2 carried by variety Mexico 54. The sequence‐characterized amplified region assays OPEO4 and PF13, which are diagnostic for an ALS resistance gene carried by the germplasm accession G10909, both tracked a possible second gene present in SPS50HB.

Management of Antracnosis with Electrochemically Activated Salt Solutions (EASSs) on Bean Culture.

Common bean (Phaseolus vulgaris L.) is an important crop for food security and for national economics for several countries worldwide. One of the most important factors of risk in common bean production is the fungal disease anthracnose caused by Colletotrichum lindemuthianum, which, in some cases, causes complete yield losses; this kind of plant disease is usually managed through the application of chemical products such as fungicides that are commonly not accepted by society. This rejection is based on the relationship of pesticides with health damage and environmental contamination. In order to help in solving these drawbacks, the present work proposes the use of electrochemically activated salt solutions (EASSs) as a safer pathogen control agent in crops, due to it having shown an elicitor and biostimulant effect on plants. With this background, this manuscript presents in vitro results of the evaluation of the inhibitory effect for multiple bean pathogens and in vivo results of EASS in the common bean-Colletotrichum pathosystem by evaluation of the infection severity and defense activation, such as secondary metabolite production and antioxidant activity. EASS presence in growth media had a strong inhibitory effect at the beginning of experiments for some of the evaluated fungi. EASSs showed an effect against the development of the disease when applied in specific doses to prevent distress in plants.

High-density DArTSeq SNP markers revealed wide genetic diversity and structured population in common bean (Phaseolus vulgaris L.) germplasm in Ethiopia

IntroductionCommon bean is one of the widely consumed food security crop in Africa, Asia, and South America. Understanding genetic diversity and population structure is crucial for designing breeding strategies.MaterialsTwo hundred and eighty-nine germplasm were recently collected from different regions of Ethiopia and introduced from CIAT to estimate genetic diversity and population structure using 11,480 DArTSeq SNP markers.ResultsThe overall mean genetic diversity and polymorphic information content (PIC) were 0.38 and 0.30, respectively, suggested the presence of adequate genetic diversity among the genotypes. Among the geographical regions, landraces collected from Oromia showed the highest diversity (0.39) and PIC (0.30). The highest genetic distance was observed between genotypes collected from SNNPR and CIAT (0.49). In addition, genotypes from CIAT were genetically more related to improved varieties than the landraces which could be due to sharing of parents in the improvement process. The analysis of molecular variance revealed that the largest proportion of variation was due to within the population both in geographical region (63.67%) and breeding status (61.3%) based classification. Model-based structure analysis delineated the 289 common bean genotypes into six hypothetical ancestoral populations.ConclusionsThe genotypes were not clustered based on geographical regions and they were not the main drivers for the differentiation. This indicated that selection of the parental lines should be based on systematic assessment of the diversity rather than geographical distance. This article provides new insights into the genetic diversity and population structure of common bean for association studies, designing effective collection and conservation for efficient utilization for the improvement of the crop.

Effects of Roasting Conditions on the Proximate Composition and Functional Properties of Common Bean (Phaseolus vulgaris) Flours

Roasting of dry beans presents the possibility of a value-added product with improved nutritional quality and potential use in different food systems. The effect of roasting on the proximate composition and functional properties of dry beans (Phaseolus vulgaris L.) was determined. Beans were roasted at 140, 170, and 200 °C for 5, 10, and 15 minutes. The moisture, carbohydrate, protein, dietary fibre, total ash and fat contents of the flours ranged from 4.58 to 6.72%, 56.21 to 60.51%, 23.09 to 26.74%, 4.12 to 7.01%, 3.94 to 4.58% and 1.28 to 2.10%, respectively. An increase in roasting temperature and time significantly reduced moisture and carbohydrate contents, but increased fat, fibre and ash contents. Foaming capacity, foam stability, water absorption index, water solubility index and water absorption capacity varied from 6.16 to 45.14%, 2.10 to 30.68%, 4.20 to 5.12 g/g, 10.74 to 17.15 g/g and 1.77 to 2.2 g/g, respectively. Increasing roasting temperature and time impacted functional properties of flours. Pasting properties of bean flour pastes were significantly reduced. Flour from roasted beans (FRBs) can serve as a functional ingredient and nutrient enhancer in the food industry. In order to increase shelf life and nutrient density of bean flours, the beans should be roasted at 200 °C.