Resistance of Bean Cultivars and Lines to Xanthomonas campestris pv. phaseoli (Smith) Dye

I. KIRYAKOV and D. GENCHEV

Institute for Wheat and Sunflower "Dobroudja" BG-9520 General Toshevo, Bulgaria

Abstract

KIRYAKOV, I. and D. GENCHEV, 2000. Resistance of bean cultivars and lines to Xanthomonas campestris pv. phaseoli (Smith) Dye. Bulg. J. Agric. Sci., 6: 525-528

Resistance of 11 bean genotypes (Phaseolus vulgaris) to different strains of Xanthomonas campestris pv. phaseoli population in Bulgaria have been studied. Plants were grown in plastic pots containing 1.5 kg of soil-sand mixture at 20-25 0C and 12h photoperiod. Leaves of four plants per genotype were inoculated at stage first trifoliate leaf by the clipping method with bacterial suspension (108 cfu/ml) of 24-48 h culture on YDC medium of the respective strain. Inoculated plants were transferred to a greenhouse at 25-27 0/20-22 0C day/night temperature and 12 h photoperiod. The disease reaction was recorded 14 day after inoculation according to a 9-degree scale, 1 being highly resistant and 9 highly susceptible. All of the 108 strains included in the study were virulent to the susceptible cultivar Dobroudjanski 7. Genotypes XAN 159, HR 45, PI 207262, Oreol and G. N. Jules were highly to moderately resistant to over 80% of the strains tested. The others 5 genotypes were highly to moderately resistant to 33.3 72.6% of the strains. Using of the studied genotypes as donors for resistance to common blight in bean breeding programs will give the possibility to cover a wider genetic variability in the population of the pathogen in Bulgaria.

Key words: common bean, resistance, Xanthomonas campestris pv. phaseoli (Smith) Dye