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Snap bean (Phaseolus vulgaris L.) is among the leading vegetables in Kenya that is mainly grown for export with the potential to increase household income. There are few programs in Kenya that focus on breeding new cultivars for increased production. The development of snap bean varieties that are resilient to the changing climate is crucial for sustainable agriculture in Kenya. To achieve this, knowledge of gene action, trait expression, and heritability is vital in effective breeding for quantitative traits like pod quality and yield. A study was conducted to investigate the inheritance of pod quality and yield traits in snap beans, which can inform the breeding of snap beans. A half diallel cross involving two indeterminate dry beans (G2333 and MCM 5001) and five determinate snap beans (Amy, Moonstone, Seagull, Serengeti and Vanilla) varieties was conducted. Data on pod traits (pod weight per plant, pod number per plant, pod length, pod diameter, pod wall fiber and pod suture string) were collected from 21 F1s and 7 parents grown in two locations (Embu and Kirinyaga Counties) in Kenya. The results showed significant genotypic and environmental effects (P < 0.001) for all traits, with significant genotype by environment (G × E) interactions for most traits. Additionally, general combining abilities (GCA) and specific combining abilities (SCA) were significant for all traits evaluated. The significance of GCA and SCA indicated the importance of both additive and non-additive gene effects in controlling the traits, although the additive gene effects were predominant. The study revealed that Vanilla and Serengeti had the highest GCA estimate for pod quality traits, while G2333 and MCM5001 had the highest GCA estimate for pod yield traits. Snap bean pod yield and quality are quantitative traits controlled by multiple genes and influenced by the environment. Therefore, the predominance of additive gene effects suggests that selection for these traits in segregating generations could yield satisfactory gains. The results of this study could impact the development of snap bean varieties that are more resilient to the effects of climate change. Thus, improving the sustainability and productivity of the agriculture sector in Kenya. [ABSTRACT FROM AUTHOR]

This research addresses the presence of Elsinoë phaseoli in Kenya, where information on the biology of this pathogen remains scarce. Employing a multifaceted approach, the study demonstrates the steps taken to isolate, identify, and characterize E. phaseoli as the pathogen responsible for scab on common bean. Field observations confirmed scab symptoms, particularly the prominent pod lesions. Elsinoë phaseoli was isolated from common bean using a targeted streaking method on older acervulus‐bearing lesions. Morphological examinations revealed a notable diversity within E. phaseoli colonies, consistent with the characteristics of the genus. Molecular identification through ITS‐rDNA sequencing confirmed isolate AscoSK1 obtained in this study as belonging to E. phaseoli, offering a robust species differentiation method. Assessing conidium production required the implementation of five different culture methods. An adaptation of the Scheper et al. (2013) method yielded the highest quantity of conidia from 25 colonies spaced at 1 cm apart, with a conidial yield of 5.0 × 106 conidia per 9‐cm‐diameter Petri dish. A higher conidial yield was attained after the colonies were pre‐incubated on potato dextrose agar in the dark at room temperature for 28 days, followed by a transfer to corn meal agar for an additional 2 days at 20°C. This emphasizes the pivotal influence of incubation duration and pre‐culture conditions on the process. This research provides insights into the biology of E. phaseoli and introduces an improved method for enhancing in vitro sporulation of the pathogen, setting groundwork for future research and handling. [ABSTRACT FROM AUTHOR]