Capacidade de combinação de híbridos simples de milho e interação com épocas de plantio

• Autor(a) principal: Castro, Laís Lopes de
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000002gj8
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/11391
• topic: Melhoramento de plantas; Zea mays L.; Análise dialélica; Griffing; GxA; GGE Biplot; Plant breeding; Zea mays L.; Diallel analysis; Griffing; GxE; GGE Biplot; CIENCIAS AGRARIAS::AGRONOMIA

The high yield obtained in the corn crop and the increases in world production are due to the advances obtained with the genetic breeding. The high productivity obtained in the corn crop and the increases in world production are due to the advances obtained with the genetic improvement. Within the breeding programs, one of the most important decision-making is the formation and choice of the base populations used in the breeding, as they are the ones that will extract the superior strains, so they must gather favorable alleles for characteristics of interest, and for that it is necessary to include several parents in the genealogy of a population. A good strategy for the formation of base populations is the identification of simple high-performance hybrids with high combining capacities for the characteristics of interest. The objective of this study was to identify promising parents and crosses for population formation for the UFG maize breeding program, considering four planting seasons. For the identification of the best parents to compose the new base population, they were evaluated in Goiânia-GO in four planting seasons during the 2018/2019 harvest under a complete diallel genetic design, 6 parents (simple hybrids) and 15 crosses (double hybrids) totaling 21 treatments in the diallel scheme and 5 other controls for comparison purposes. As the behavior of the genotypes is greatly influenced by environmental variations, the analysis of genotype interaction with environments like GGE Biplot was performed. The plant height and ear height characters can be used for selection in the four environments based on the CGC values. There was no pattern of behavior for the determination coefficient estimates (R2) over the four experiments. Parent G1 was better for decreasing the corn cycle with negative flowering values, but in general it presented poor values for CGC and CEC. Parents G2, G3 and G4 showed the best CGC values for the primary production components, and parent G5 as the most stable, although with CGC below the general average. The G1 x G2 cross obtained the highest CEC and at the same time was the most unstable. The G1 x G4, G3 x G6 and G1 x G6 crosses were the most stable and with CEC values higher than the general averag