Evaluation of resistance of common bean genotypes to Agroathelia rolfsii and Macrophomina phaseolina

Abstract

Common bean (Phaseolus vulgaris L.) is a key crop for food security in Brazil, standing out for its affordability and high nutritional value. However, fungal diseases represent a significant threat to its production, especially in the Brazilian Northeast. This study aimed to evaluate the genetic resistance of common bean landraces to the diseases gray stem rot, caused by Macrophomina phaseolina, and collar rot, caused by Agroathelia rolfsii. Twenty common bean varieties were tested for both pathogens at different times. Variability in the responses of the varieties to the fungi was observed. Some materials, such as Lavandeira and Carrapatinho, showed high resistance in one of the bioassays, and medium susceptibility in the other. In the case of Agroathelia rolfsii, Caianinha, Lavandeira and Carrapatinho showed high resistance. The results suggest that some varieties created may offer resistance to the pathogens tested, but further studies are needed to understand the type of resistance found and its durability. Therefore, these varieties may be potential sources of resistance for future genetic improvement and cultivation programs in areas affected by these diseases. This study highlights the importance of searching for genetic resistance to ensure food security and the sustainability of bean production in Brazil.