Factor analysis applied to simultaneous selection for resistance to anthracnose and angular leaf spot

Abstract

AbstractDiseases such as anthracnose (Colletotrichum lindemuthianum) and angular leaf spot (Pseudocercospora griseola) can occur in common bean and compromise crop production, especially if susceptible cultivars are grown under conditions favorable to these diseases. The most efficient and sustainable alternative for controlling these diseases is the use of resistant cultivars. The identification of sources of resistance and the use of tools that assist in accurate selection of resistant cultivars are crucial to the success of breeding programs. The aim of this study was to characterize 67 carioca common bean cultivars recommended in Brazil regarding reaction to races 65, 73, 81, and 89 of C. lindemuthianum and to races 63‐23 and 63‐63 of P. griseola and to verify the application of factor analysis in the selection of cultivars resistant to both pathogens. The cultivars and resistant controls BRS Esplendor and MAIII.16‐159 were inoculated in a greenhouse in two experiments for each race. Cultivars were assessed for resistance to multiple races of anthracnose and angular leaf spot using artificial inoculation of plants at V2 stage. Factor analysis proved to be a good alternative for accurate selection of resistant cultivars. The percentage of cultivars simultaneously resistant to all races was low (8.95%). The cultivars Rudá R, VC 15, IAC‐Apuã, IAC‐Carioca Pyatã, BRSMG Amuleto, and BRS FC104 selected by factor analysis showed resistance to anthracnose and angular leaf spot. Therefore, these cultivars are potential sources of resistance for incorporation in bean breeding programs.