Reação de cultivares de feijoeiro comum à mancha angular em casa-de-vegetação

Resumo

Twenty-three common bean (Phaseolus vulgaris) genotypes were tested for reaction to angular leaf spot disease caused by Phaeoisariopsis griseola in the greenhouse. All genotypes were tested with monosporic isolates Ig 664 and Ig 669, characterized as pathotypes 63.23 and 63.19, respectively. Fourteen-day-old plants (vegetative stage V3) were inoculated with a suspension containing 2.5 × 104 conidia/mL. This suspension was applied to the upper and lower leaf surfaces. Disease symptoms were evaluated 14 and 18 days after inoculation by using a rating scale varying from 1 (no symptoms) to 9 (≥ 25% of leaf area with angular leaf spot lesions). Culivars BRS Valente, CNFC 10281, CNFP 10138, BRS Grafite, BRS Requinte, BRS Pontal, MAR 02, Cornell 49-242 and AND 277 showed resistance to both isolates. Cultivars Carioca Rubi, CNFC 9504, CNFC 10150 and Soberano were susceptible to both pathotypes. Pathotype 63.23 was the most virulent. The new resistance sources identified in this work could be used in common bean breeding programs aiming to incorporate resistance to angular leaf spot in new common bean cultivars.

Descrição

Palavras-chave

Resistência genética, Genetic resistance, Phaeoisariopsis griseola, Phaseolus vulgaris

Citação

REIS-PRADO, Fabiana G. et al. Reação de cultivares de feijoeiro comum à mancha angular em casa-de-vegetação. Fitopatologia Brasileira, Brasília, DF, v. 31, n. 3, p. 306-309, 2006.