Data/hora: 04/06/2024 06:27:29

Provedor de dados: | Genetics and Molecular Biology
País: | Brazil
Título: | Responses to reciprocal recurrent selection and changes in genetic variability in IG-1 and IG-2 maize populations
Autores: | Santos,Mateus Figueiredo; Moro,Gustavo Vitti; Aguiar,Aurélio Mendes; Souza Jr.,Cláudio Lopes de.
Data: | 2005-12-01
Ano: | 2005
Palavras-chave: | Maize; Responses to selection; Genetic variances; Genetic correlations.
Resumo: | This paper reports the effects of three cycles of reciprocal recurrent selection (RRS) on the means, genetic variances, and on the genetic correlations for several traits in the IG-1 and IG-2 maize (Zea mays L.) populations. Interpopulation full-sib progenies from cycle zero (C0) and from cycle 3 (C3) of RRS were evaluated in two locations. RRS was highly effective to improve the traits according the objectives of the program: grain yield and prolificacy increased significantly, while plant height, ear height, and ear placement decreased significantly. Genetic variances for all traits decreased significantly from C0 to C3, but the genetic correlations did not change consistently across the cycles of selection. The expected responses to the fourth cycle of RRS and the probability of selecting double-crosses from C3 that outperform those from C0 showed that the decreases in the genetic variances were not great enough to limit the continued improvement of the populations as well as the use of the improved populations as sources of inbred lines to develop commercial hybrids. However, if the magnitudes of the genetic variances continue to decrease, new sources of improved germplasm should be incorporated into both populations to allow the continued improvement of the interpopulation by RRS.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000500021
Editor: | Sociedade Brasileira de Genética
Relação: | 10.1590/S1415-47572005000500021
Formato: | text/html
Fonte: | Genetics and Molecular Biology  v.28 n.4 2005
Fonte: | info:eu-repo/semantics/openAccess