Topcross hybrids in papaya (Carica papaya L.): evaluation of the potential for increasing fruit quality in new cultivars

Abstract

ABSTRACT Multivariate analyzes such as selection indexes are one of the ways to select superior papaya genotypes with adequate quality to the consumer market, becoming more efficient after inferences made in the population from the estimate of genetic parameters. Thus, this study aimed to estimate genetic parameters and select papaya topcross hybrids for traits related to fruit quality through selection indexes. The analysis of variance was performed, and the genetic parameters and means test were estimated. The indexes of Smith and Hazel, Pesek and Baker, Mulamba and Mock, and Williams were applied to determine the genetic gains. The genetic parameters indicated a greater environmental influence for firmness, and soluble solids content, where the fruit weight presented the highest genetic variation. The selection showed a reduction in gains for at least one of the essential traits in the quality of the fruits, such as fruit and pulp firmness, soluble solids content, or pulp volume percentage. The Mulamba and Mock index demonstrated satisfactory gains for all these traits with minimal reduction in the others, which is considered the most appropriate for the selection of eight papaya hybrids (UCHJ16-014, UCHJ16-034, UCHJ16-006, UCHJ16-026, UCHJ16-013, UCHJ16-012, UCHJ16-025, and UCHJ16-016).