Potencial genético e seleção de progênies de soja

Abstract

Soybean (Glycine max (L.) Merr.) is one of the main agricultural crops in the world, standing out for its economic and social importance, especially in Brazil, the world's largest producer. Productive success derives from the advances obtained by genetic improvement programs, which aim at more productive genotypes and with resistance to biotic and abiotic factors. In this context, the present work aimed to evaluate soybean progenies in the F4 generation, estimate genetic parameters, selection gains and identify promising genotypes. The experiment was conducted in Uberlândia-MG in February in the 2024/25 harvest, in DBC, with 25 genotypes, 20 of which were F4 progenies from biparental crosses and five conventional cultivars used as parents. Sixteen traits related to the cycle, plant architecture, yield components and grain yield were evaluated. Genetic-statistical analyses were performed in the Genes Program. The analysis of variance revealed significant genetic variability for all traits evaluated (p ≤ 0.05), except for the number of productive nodes. The experimental coefficients of variation ranged from 2.84% for days to maturity to 47.67% for the number of single-seed pods. Heritability estimates were high for most traits, ranging from 28.24% to 91.31%, particularly for plant height at maturity, indicating strong genetic control and good prospects for selection. Grain yield showed wide variation among genotypes, with values ranging from 1,457 to 2,999 kg ha⁻¹, with the progenies UFU_TMGxBRS_20, UFU_7010xBRS_8, and UFU_TMGx7010_6 standing out. The greatest direct selection gains were observed for grain production per plant (26.45%) and grain yield (26.07%). According to the Mulamba and Mock selection index, balanced gains were obtained, particularly for the number of pods with three grains (28.51%) and grain yield (16.4%). These results indicate high potential for selecting superior progenies in the breeding program. It is concluded that the evaluated progenies have the potential to advance the breeding program, particularly genotypes with favorable agronomic traits and higher grain yield. The UFU_TMGxBRS_20 genotype showed superior performance, with high values for total number of pods, seed weight per plant, and yield, and is considered promising for continued inclusion in the breeding program.