Potencial genético e correlação entre caracteres em população de milho branco

• Autor(a) principal: Watanabe, Ikio Aline Monteiro
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/11912
• topic: Zea mays; Melhoramento de plantas; Correlação genética; Genética quantitativa; Herdabilidade; Zea mays; Plant breeding; Genetic correlation; Quantitative genetics; Heritability; CIENCIAS AGRARIAS::AGRONOMIA::CIENCIA DO SOLO

White maize is used for human consumption in the form of grits, flour and starch. It stands out as an alternative to small farmers, as it has a higher commercial value. However, there are few white maize cultivars on the market, and it is important to develop higher yield cultivars of this type. Among the several maize breeding methods, recurrent selection stands out for allowing the increase of the frequency of favorable alleles in population for several selective cycles. However, recurrent selection is only effective when using populations with good averages and genetic variability for the traits of interest. Thus, the objective of this study was to evaluate the agronomic performance, genetic variability and expected genetic gains of a white maize population; and to estimate the genetic, phenotypic and environmental correlations between agronomic traits, including grain yield. For this purpose, 169 half-siblings progênies were evaluated using a 13 x 13 triple lattice design, in 2018 second crop, in the UFG, Goiânia-GO and UFJ, Jataí-GO. The traits evaluated were: number of days to anthesis, number of days to silking, anthesis-silking interval, plant height, ear height, ear ratio, stalk lodging, ear prolificacy, kernels per row, number of kernels per row, ear diameter, ear length, cob diameter, ear weight and grain yield. Significant differences were found among progenies for all traits, except stalk lodging, indicating the presence of variability. The genetic gains with selection ranged from -26.26%, for anthesis-silking interval, to 9.04%, for ear prolificacy. All traits, except ear diameter, exhibited at least one significant genetic, phenotypic or environmental correlation estimate, indicating that changes in one trait may change the mean of other correlated. It is concluded the white maize population presents genetic variability and satisfactory means for most agronomic traits, including grain yield; thereefore, the population has the potential to be used in a recurrent selection program. Indirect selection for grain yield is possible through direct selection for number of kernels per row and ear weight.