Índice de seleção para caracteres agronômicos em populações segregantes de soja

• Main Author: Bizari, Eduardo Henrique [UNESP]
• Publication Date: 2014
• Format: Master thesis
• Language: por
• Source: Repositório Institucional da UNESP
• Download full: http://hdl.handle.net/11449/110319
• topic: Soja; Soja - Melhoramento genético; Seleção de plantas - Melhoramento genetico; Genetica vegetal; Plantas oleaginosas; Plant-breeding

In soybean breeding, the selection process is complex and highly influenced by the environment. An alternative to facilitate this process is the use of selection indexes, thus making possible the selection of desirable genotypes in early generations of breeding programs. The main this work was to compare different selection indexes in segregating soybean populations, indicating the superior methods in some situations and proposed economic weights, aiming higher gains. Were used the indexes direct and indirect selection, classical index of Smith and Hazel, index based sum of ranks of Mulamba and Mock, index base of Williams, index based desired gains of Pesek and Baker and index of genotype-idiotype distance. The genetic material consisted of seven soybean populations in the F5 generation, totaling 386 progenies in randomized block Federer, for traits number of days to maturity, plant height at maturity, height of the first pod, lodging, agronomic value, number of pods per plant, oil content and yield grain. The classic and base indexes presented lower variations in relation to the gains obtained in different situations and studied economic weights. The index based on the sum of ranks with the characters agronomic value and grain yield as a major economic burden beyond one (1) provided the most favorable gains in the present study