Comparative study of common bean cultivars on the yield potential, resistance to biotic and abiotic stresses and grain quality

Abstract

Carioca bean has been leading the Brazilian market since its discovery. In the 1990s, the preference for this grain color was accentuated, with the launching of the cultivar Pérola, which due to the larger size of the grains, yield potential and resistance to wilt of Fusarium, has became a market standard and, being widely used as progenitor in the various national breeding programs. Due to the increased demand for this type of grain, several cultivars were introduced, in an attempt to join together on each cultivar the agronomic and market characteristics that complement each other. However, our hypothesis is that by improving plants for lighter seeds with greater resistance to darkening, the plants became more susceptible to diseases, especially Fusarium wilt. In this search for cultivars that served the entire production chain, the cultivar TAA Dama was launched in 2014, which presents a great prominence in the Brazilian market, due to the lighter tegument with seed darkening tolerance after harvest, which allows the longer storage, hence to be marketed in times of higher product valorization, however, it is not considered resistant to Fusarium wilt. The objective of this project is to elucidate the relationship between the seed darkening and the susceptibility to the main bean diseases (Fusarium wilt, anthracnose and bacterial blight), as well as comparing the progress of breeding programs for carioca tegument, evaluating the main cultivars launched in the Brazilian market, since the launch of the cultivar Pérola. It will be evaluated 30 carioca genotypes of common bean from different Brazilian Research Institutions. These genotypes will be evaluated jointly in nine valid environments in the State of São Paulo, regarding the diseases resistance (natural occurrence in the field and under controlled conditions); seed darkening; cooking time; grain yield potential; stability and adaptability of production; besides tolerance to abiotic stresses (drought and high temperature). It is expected that with this study we will prove the relationship between the susceptibility of common bean to the main diseases with the seed darkening, in addiction estimating the effective gains and losses in these cultivars throughout the process of crop improvement. (AU)