BREEDING FOR RESISTANCE TO BEAN GOLDEN MOSAIC-VIRUS IN AN INTERRACIALPOPULATION OF PHASEOLUS-VULGARIS L

Eighty-three F2-derived F8 recombinant inbred lines (RILs) randomly se lected from a population (TY 8419) of two common bean genotypes (Pinto UI 114 x ICA Pijao), the two parents, and a control cultivar (Topcrop ) were screened for their reaction to bean golden mosaic virus (BGMV) under glasshouse conditions. A randomized complete block design with t wo replications was used. Data were recorded for disease incidence, fo liar yellowing, number of pods and seeds, and yield. Significant (P < 0.05) differences among the 83 RILs were recorded for all traits. Of t hese RILs, 11 lines did not develop any symptom, 24 lines had a mean d isease incidence of 8%, 28 lines had a disease incidence of 26.6% and developed intermediate mosaic symptoms, and 20 lines were more suscept ible (> 50% disease incidence and severe yellowing) than either of the parents, which had 25% to 38% disease incidence and moderate symptoms . Heritability for disease incidence was 0.54 +/- 0.01, for foliar yel lowing 0.36 +/- 0.13, for pods plant-1 0.69 +/- 0.01, for seeds plant- 1 0.54 +/- 0.09, and for yield plant-1 0.49 +/- 0.01. Gains from selec tion (at 20% selection pressure) for these traits were 49.5%, 31.6%, 2 4%, 0%, and 20%, respectively, over the mean value of all RILs. Correl ation coefficients between disease incidence and foliar yellowing and among yield and its components were positive. Disease incidence and fo liar yellowing showed negative associations with yield and its compone nts.