Development of white common beans for the processing industry in East Africa: Adaptability, resistance to selected diseases, cooking time and canning quality

Abstract

Common bean (Phaseolus vulgaris L.) provides dietary protein, energy, fiber and micronutrients especially, iron and zinc to over 800 million people in Africa and Latin America. The crop has various seed types, but white beans are very popular in the processing industry. This study aimed to investigate agronomic and canning quality, cooking time and the response of white beans to root rots and angular leaf spot (ALS) that cause significant yield losses in bean production eastern Africa. Small and large seeded beans improved for drought tolerance were evaluated from 2013 to 2018. Significant (P<0.001) differences existed among the 151 genotypes for response to three pathogens (Fusarium cuneirostrum, Pythium ultimum and Pseudocercospora griseola), cooking time and canning quality traits. It was possible to select for single, dual and triple disease resistance. Resistance to each of the pathogens was expressed in 24-75% of the genotypes; while dual resistance to any two pairs of the pathogens occurred in 10-44% of the genotypes. The four genotypes; ICNBunsixSxB405/4C-1C-1C-88, RAZ-11, ETSNAP18 and ETSNAP3 that expressed resistance to three pathogens were cooked in 46-56 minutes, and are recommended as sources of resistance for breeding, but could be further improved for fast cooking and canning quality since a general below average canning quality was exhibited. Sixty-eight genotypes were cooked in <50 minutes while 24 expressed good to excellent visual canning quality. The genotypes like RAZ-120, RAZ36-Caballero, NavyLine-60, NavyLine-25, ZABR16573-25F22, ZABR16575-60F22, ETSNAP33, Bifortsmallseeded-15 and ZABR16574-37F22, that cooked in less than 45 minutes, exhibited good to excellent canning quality and resistant to intermediate response to the evaluated diseases were recommend for breeding purpose and for further evaluation for possible promotion.