Assessment of genotypic variability and Genome Wide Association studies for cooking time and canning quality traits in common bean ( Phaseolus vulgaris L.)

Abstract Developing common bean genotypes that possess short cooking time and good traits for canning is very key in accelerating bean consumption among both the urban poor and the middle class population. With the objective of assessing the genotypic variability and with Genome wide association studies (GWAS) identify SNP markers associated with the two traits, 250 common bean accessions were evaluated using alpha lattice design with two replications and two seasons. Three months post-harvest, the bean grains were evaluated for the two traits. Analysis from mixed models revealed significant variation for both traits among the 250 accessions tested. Cooking time ranged from 51.56 to 215 minutes, with 11 genotypes cooking in less than 60 minutes and total canning quality score ranged from 41.3 to 84% with 31 genotypes scoring 76% and above. GWAS conducted on 217genotypes revealed a total of 47 significant marker trait associations for the two traits; on chromosome Pv01 for cooking time(CT) and washed drain coefficient (WDC), viscosity, WDC, washed drain solids(WDS), splitting and hydration coefficient(HC) on chromosome Pv02, WDS, HC, free starch(FS) and splitting on Pv03, CT, WDC and WDS on Pv04, viscosity, splitting, FS, colour and CT on Pv05. Clumping on Pv06, visual appeal, colour and viscosity on Pv07, visual appeal, clumping, splitting and WDC on Pv08, clumping, viscosity, FS and on Pv09, colour, FS, WDS and clumping on Pv010, CT, FS, clumping, viscosity and WDS on Pv011. Possible candidate genes including; phvul.007G2803001 and Phvul.007G280700.2 both on chromosome 7 and Phvul.005G161200.1 on chromosome 5, all associated with seed coat colour were identified. Besides their usefulness in breeding research, these studies identified genotypes whose shorter cooking time and good canning quality traits could benefit the consumption and processing industries.