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Developing improved common bean varieties with short cooking time (CT) and good canning quality traits (CQTs) is very key for accelerating bean consumption among the urban and middle‐class population. The objective of this study was to assess the genotypic variability and identify single nucleotide polymorphism (SNP) markers associated with CT and CQTs in common bean. A total of 250 common bean accessions were evaluated under field conditions for two seasons using alpha lattice design with two replications. Three months post‐harvest, the dry bean grains were evaluated for CT and CQTs. Significant variation was observed among the 250 common bean accessions tested for both traits. CT ranged from 51 to 215 min, with 11 genotypes cooking in less than 60 min. The percentage total CQTs' score ranged from 41% to 84% with 31 genotypes scoring 76% and above. Forty‐seven significant GWAS signals were detected for CT on chromosomes Pv01, Pv04, Pv05 and Pv11 and CQTs on Pv01, Pv02, Pv03, Pv04, Pv05, Pv06, Pv07, Pv08, Pv10 and Pv11, respectively. Positional candidate genes including Phvul.005G161200 on chromosome Pv05, Phvul.007G2803001 and Phvul.007G280700 on chromosome Pv07 were associated with seed coat colour retention of the canned beans. Besides their usefulness in breeding research, the identified bean genotypes with shorter CT and good CQTs could enhance bean consumption and processing industries. [ABSTRACT FROM AUTHOR]

Genome‐wide association study (GWAS) was conducted to determine the genetic architecture of yield component and photosynthetic (PS) traits in 256 common bean (Phaseolus vulgaris L.) genotypes from the Andean gene pool. The panel was evaluated under drought stress (DS) and non‐stress (NS) conditions at two locations for two seasons in Uganda and genotyped with 260K single nucleotide polymorphism (SNP) markers. Significant association signals were detected for yield component and PS traits on chromosomes Pv02, Pv03, Pv04, Pv06, Pv09, Pv10, and Pv11. Colocalized GWAS signals were detected for pod weight per plant (PW) and seed yield per plant (SY) on Pv06 with ten significant markers and for PhiNPQ, LEF, Phi2, and PhiNO on Pv11 under DS. Positional candidate genes were identified within the 1.76 Mb common region for PW and SY under DS on Pv06 including Phvul.006G117500, Phvul.006G119800, and Phvul.006G130500 annotated as plant invertase/pectin methylesterase inhibitor (INH/PMEI) superfamily protein, involved in sucrose metabolism and signaling. Phvul.006G121200, 14.9Kb upstream of marker S06_23021418 (23.02Mb) on Pv06, encodes Protein phosphatase 2C family protein involved in ABA signaling pathway. Positional candidate genes for PS traits PhiNPQ, LEF, Phi2, and PhiNO on Pv11 under DS were identified including Phvul.011G178200, Phvul.011G178250, Phvul.011G178300, and Phvul.011G178500 between 48.94–49.96 Mb annotated as "RING/U‐BOX SUPERFAMILY PROTEIN", ubiquitin ligase (E3) involved in ABA‐mediated responses. Significant markers associated with colocalized GWAS signal for SY and PW on Pv06 identified in this study can be validated for marker assisted breeding to improve drought tolerance in large‐seeded Andean beans. Core Ideas: Genomic regions important for drought tolerance in large‐seeded beans were identifiedYield traits did not associate with photosynthetic traitsCandidate genes associated with ABA signaling pathway appear important in drought tolerance [ABSTRACT FROM AUTHOR]

The study was conducted to determine the role of training design and trainee characteristics in predicting the transfer of agronomic training among bean seed farmers in Uganda. Gender differences in levels of transfer were also studied. Data were from a sample survey of 300 respondents. Independent t‐tests and hierarchical multivariate regression were used to answer the specific issues of the study. Results showed transfer was generally high, with women having a significantly higher training transfer than men. Using the Learning Transfer System Inventory (LTSI) model, we identified factors relating to trainee characteristics – motivation to transfer, readiness to learn and performance self‐efficacy – that have shown a significant relationship with the transfer of training. We concluded by discussing potential implications for both theory and practice. [ABSTRACT FROM AUTHOR]

There are several hurdles to ensure sustainable seed production and consistent flow of improved legume varieties in sub‐Saharan Africa (SSA) and South Asia (SA). The unreliable demand, autogamous nature of most of the grain legumes, and slow variety replacement rate by smallholder farmers do not provide strong incentive for private seed companies to invest in legume seed business. Unless a well thought‐out and comprehensive approach to legume seed delivery is developed, current seed shortages will continue, eroding emerging market opportunities. The experiences reported here are collated through a 10‐year partnership project, the Tropical Legumes in SSA and SA. It fostered innovative public–private partnerships in joint testing of innovative market‐led seed systems, skills and knowledge enhancement, de‐risking private sector initiatives that introduced in new approaches and previously overlooked entities in technology delivery. As new public and private seed companies, individual seed entrepreneurs and farmer organizations emerged, the existing ones enhanced their capacities. This resulted in significant rise in production, availability and accessibility of various seed grades of newly improved and farmer demanded legume varieties in the target countries. [ABSTRACT FROM AUTHOR]

Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement. [ABSTRACT FROM AUTHOR]

Common bean (Phaseolus vulgaris L.) is an important legume crop worldwide. The International Centre for Tropical Agriculture (CIAT) and its national partners in Africa aim to overcome production constraints of common bean and address the food, nutrition needs and market demands through development of multitrait bean varieties. Breeding is guided by principles of market‐driven approaches to develop client‐demanded varieties. Germplasm accessions from especially two sister species, P. coccineus and P. acutifolius, have been utilized as sources of resistance to major production constraints and interspecific lines deployed. Elucidation of plant mechanisms governing pest and disease resistance, abiotic stress tolerance and grain nutritional quality guides the selection methods used by the breeders. Molecular markers are used to select for resistance to key diseases and insect pests. Efforts have been made to utilize modern genomic tools to increase scale, efficiency, accuracy and speed of breeding. Through gender‐responsive participatory variety selection, market‐demanded varieties have been released in several African countries. These new bean varieties are a key component of sustainable food systems in the tropics. [ABSTRACT FROM AUTHOR]

Drought stress is becoming one of the most important abiotic factors limiting productivity of common bean (Phaseolus vulgaris L.) globally. The objective of this study was to conduct a quantitative trait loci (QTL) analysis of drought tolerance in a recombinant inbred line (RIL) mapping population genotyped using single nucleotide polymorphism (SNP) markers. The RIL population was developed by crossing Portillo × Red Hawk, two Andean bean genotypes contrasting in reaction to drought stress and evaluated at two locations in Uganda for two seasons under drought stress (DS) and non‐stress (NS) conditions. Eighteen significant QTL signals were identified for phenology, yield component and partitioning traits on chromosomes Pv01, Pv02, Pv03, Pv04, Pv06, and Pv11 under DS and NS conditions. Quantitative trait loci for seed yield per plant (SY) were detected on Pv01, Pv02, Pv03, Pv04, and Pv06 under DS conditions. Colocalized QTL signals for pod weight per plant and SY were identified under DS on Pv01 (45.15 Mb) and on Pv02 (0.12 Mb), for phenology and SY on Pv03 near marker ss715639424 (40.16 Mb), and for SY and harvest index on Pv06 (17.92 Mb). Two candidate genes related to flowering were identified within a 35‐kb region from the ss715639424 marker on Pv03. Gene Phvul.003G189100 (30.3 kb) encodes "AGAMOUS‐LIKE 65 (AGL65)," which is essential for pollen development, and gene Phvul.003G189300 (17.9 kb) encodes "CYCLING DOF FACTOR 3 (CDF3)" that regulates flowering time. The same SY QTL, SY3.3PR on Pv03, was previously detected in Mesoamerican germplasm and could be used through marker‐assisted breeding to improve SY of Andean beans grown under DS. [ABSTRACT FROM AUTHOR]