Desempenho de populações de milho sob estresse hídrico e de nitrogênio

• Ano de defesa: 2006
• Autor(a) principal: Silva, Ricardo Gonçalves
• Orientador(a): Cruz, Cosme Damião
• Banca de defesa: Coimbra, Ronaldo Rodrigues , Souza, Moacil Alves de , Carneiro, José Eustáquio de Souza
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Genética e Melhoramento
• Departamento: Genética animal; Genética molecular e de microrganismos; Genética quantitativa; Genética vegetal; Me
• País: BR
• Palavras-chave em Português: Milho; Estresse abiótico; Divergência genética; Nitrogênio; Fósforo; Eficiência de utilização
• Palavras-chave em Inglês: Maize; Stress; Genetic divergence; Nitrogen; Use efficiency
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA::MELHORAMENTO VEGETAL
• Link de acesso: http://locus.ufv.br/handle/123456789/1414

In order to evaluate the performance of some maize populations under water and nitrogen stresses, eight experiments were set up in Unaí county-MG, on March 2005. So, four experiments were constituted by 49 half-sib families (FMI) randomly taken from the population UFVM 100, whereas other four ones were constituted by 49 FMI randomly taken from the population UFVM 200. The 7 x7 lattice design was used with two replicates, in each experiment. The experimental plot was integrally used, as being constituted by one line with 5m length and 0.9m spacing, with 25 plants per line, so representing an approximate population of 55,000 plants by hectare. To evaluate the performance of both populations under water stress condition, they were subjected to optimum conditions of irrigation and water deficit (irrigation interruption) during critical development periods. Both populations were submitted to two nitrogen fertilization levels (high and low nitrogen availabilities) in order to evaluate their performance under nitrogen stress. In those eight experiments, the yield of the maize grains in each plot and subsequent conversion into maize grain yield by hectare were evaluated. So, the occurrence of low concordance between the performance of the half-sib families under water deficit conditions and normal irrigation, as well as under high and low nitrogen availability conditions was proved, therefore indicating the need for a specific improvement program in order to obtain a material adapted to stress conditions.