High temperature increases cooking time and seed darkening of common beans
High temperature is one of the main environmental factors that limit crop performance. It may also influence seed formation and quality. We compared the effect of high temperatures on seed darkening and cooking time of 12 genotypes of common beans. The experiments were sown in summer and in fall/winter growing seasons in three municipalities of São Paulo state (Campinas, Votuporanga, and Ribeirão Preto). A randomized block experimental design was adopted with four replications, analyzed in a 2 x 3 x 12 factorial arrangement; the factors were two crop seasons, three locations and 12 genotypes. After harvest, the following seed traits were evaluated: cooking time soon after harvest (CTH), after 30 days of storage (CT30), and after 60 days of storage (CT60); seed color soon after harvest (COLH), after 30 days of storage (COL30), and after 60 days of storage (COL60). Individual variance analyses were performed followed by average test and GGE-biplot interaction of factors analysis. Seed darkening was significantly affected by the crop season factor at all evaluation times, though there was no significant effect on cooking time. Significant effects on all variables were also found for location and genotypes. In the summer growing season, darker seeds were obtained, and among the locations, the seeds produced in Campinas were lighter in color. Increases in cooking time and in seed darkening were found with increases in storage time. The genotypes BRS Estilo, IAC Diplomata, Pérola, BRS Agreste, and IAC Imperador exhibited better seed quality (shorter cooking times and colors in the desired range ) at all locations in the summer season.