Abstract:
The common bean (Phaseolus vulgaris L) is the most important food legume consumed worldwide. Sustainable production of the common bean in Tanzania is hampered by number of constrains including angular leaf spot (ALS), common bacterial blight (CBB), bean common mosaic virus/bean common mosaic necrosis virus (BCMV/BCMNV) and anthracnose (ANTH) diseases. The objective of this study was to develop common bean lines which will have resistances to ALS, CBB, BCMV/BCMNV and ANTH diseases by incorporating Co-42 and Co-6 resistance gene for anthracnose in bean line that has angular leaf spot, common bacterial blight, bean common mosaic virus/bean common mosaic necrotic virus and anthracnose disease resistance. Two donor parents of common bean cultivar C4-1308B-3E-8-B and AB 136 were used as a source of anthracnose resistance and one recipient parent line Vax3 x Mex54 x Mshindi. Crosses for creating generation of segregating population and evaluation for anthracnose disease was done under screen house and field conditions. Significant genetic variation (≤ 0.05) for anthracnose disease was noted. Moreover F1 and F2 plants in all crosses showed significant (≤ 0.05) level of resistance to anthracnose.Thus research work was successful in incorporating anthracnose resistance genes in adapted bean lines and recommended that hybridization by pyramiding genes for disease resistances may therefore be used to improve bean genotype by incorporating the disease traits from donors to a single genotype comprising many diseases in it. It is recommended that theF2 populations created in this study be advanced for further evaluation to ascertain anthracnose, CBB, ALS, BCMV/BCMNV disease resistance, and agronomic data.
