Potential parents of carioca bean for use in breeding aiming resistance to Colletotrichum lindemuthianum

Abstract

Carioca common bean (Phaseolus vulgaris L.) is the most produced and consumed in Brazil. The production of carioca bean is affected by fungal diseases such as anthracnose, caused by the fungus Colletotrichum lindemuthianum. Most sources resistant to anthracnose, used in crosses by breeding programs are not derived from the commercial group or are poorly productive and less adapted. Thus, the objective of this study was to characterize 40 carioca bean cultivars already recommended in Brazil for their reaction to C. lindemuthianum races 65, 73, 81, and 89. The cultivars and the resistant control, BRS Esplendor, were inoculated in a greenhouse with two different experiments for each race. Seedlings with fully expanded primary leaves were inoculated with a suspension of each pathogen race and assessed after 12 d. Among the 40 cultivars assessed, 12.5, 2.5, 12.5, and 15% resistant to one, two, three, and four races of C. lindemuthianum, respectively. The cultivars IAC Formoso, IAC-Carioca Pyatã, IAC-Apuã, VC 15, BRS Notável, and IPR Campos Gerais were resistant to the four races, constituting parental sources of resistance to the pathogen. In regions that favor the occurrence of anthracnose in common bean, cultivars with certain levels of resistance should be selected. Therefore, the important information obtained will be made available to growers and those offering technical assistance to growers.