Genetic parameters, selection gains and associations between characters of Carya illinoinensis using mixed models

Abstract

The objective of this work was to estimate the genetic parameters of pecan (Carya illinoinensis) cultivars through mixed model analyses of data on vegetative growth, fruit production, and fruit quality traits. The study was conducted from 2021 to 2023, using the Barton, Desirable, Elliot, Mohawk, Jackson, Shoshoni, Stuart, and Success pecan cultivars, in the municipality of Santana do Livramento, in the state of Rio Grande do Sul, Brazil. The experimental design was completely randomized. Each replicate was composed of ten plants, totaling 80 plots. Nut vegetative growth, production, and quality were evaluated. The influence of the genotype x environment interaction on production traits and nut quality was confirmed. However, these effects were not observed on vegetative growth. Production per plant and productivity per hectare exhibited positive correlations with production efficiency in relation to canopy volume. For the vegetative and production traits, broad-sense individual heritability is low, suggesting a strong environmental influence. However, for the fruit quality traits, heritability is medium to high, indicating a greater genetic contribution and, therefore, a greater potential for response to selection.