Genetic inheritance and selection for multiple traits in segregating wheat populations

Abstract

The objective of this work was to investigate genetic inheritance, selection gain, and simultaneous selection for multiple traits of interest in segregating wheat populations. Crosses were performed between genotypes 'Frontana', 'CD 1440', 'CD 105', and 'BRS Sabiá' and the F₁ and F₂ generations; the parents were sown in a field in 2020. From each plant, traits were obtained for germination in the spike, days from emergence to heading, plant height, number of tillers per plant, spike mass, number of spikelets per spike, grain mass per spike, number of grains per spike, and plant grain mass. In addition to the means, the following parameters were obtained: phenotypic, genetic, and environmental variances; broad-sense heritability; and selection gain. All traits showed quantitative inheritance controlled by many genes and influenced by the environment. In most traits, the segregated F₂ populations closely resembled the parents, notably for sprouting in the ear, influenced by the environment. Days from emergence to heading and plant height showed a high heritability and good selection gains, while yield components showed variability for advancements in selection. Simultaneous selection reduced the number of superior individuals, reinforcing the importance of using multivariate methodologies. Thus, the genetic progress depends on strategies that consider quantitative inheritance and adopt multivariate approaches to maximize gains.