Seasonal and genetic influences on sex expression in a backcrossed segregating papaya population

This study aimed to evaluate the genetic and seasonal influence on sex expression in segregating generations of papaya elite and backcrossed genotypes. In the four seasons of the 2005/2006 growing season, 200 hermaphrodite plants were evaluated. Of the eight studied traits, four were related to flowering and four to fruiting, i.e., to the percentage of normal, deformed, sterile, and total number of flowers, as well as the percentage of total, carpelloid, pentandric, and marketable fruits. Significant differences due to the genotype x season interaction were verified. Based on the genotypic determination coefficient and the variation index it was concluded that winter and spring are most appropriate for the selection of superior genotypes. Thus, selection in early stages of plant development is more successful, indicating that the physiological age may also be a factor involved in the expression of the above traits.