Combining capacity and heterosis for resistance to Puccinia polysora Underw. in maize

Authors

  • Herberte Pereira da Silva Sementes Dow Agrosciences
  • Mauricio Pires Machado Barbosa Universidade de São Paulo; Escola Superior de Agricultura Luiz de Queiroz; Departamento de Entomologia, Fitopatologia e Zoologia Agrícola
  • Luciano Lourenço Nass Embrapa Recursos Genéticos e Biotecnologia
  • Luis Eduardo Aranha Camargo Universidade de São Paulo; Escola Superior de Agricultura Luiz de Queiroz; Departamento de Entomologia, Fitopatologia e Zoologia Agrícola

DOI:

https://doi.org/10.1590/S0103-90162001000400020

Keywords:

diallel analysis, southern rust, disease resistance, plant breeding

Abstract

Genetic resistance is the most efficient way of controlling maize leaf diseases. To evaluate the specific and general combining ability (CGE and CGC, respectively) as well as heterosis for resistance to Puccinia polysora, nine inbred lines and a partial diallel set of their 36 F1 hybrids were used in experiments conducted in three environments. Disease severity was evaluated in the whole plant (PI) and in the leaf positioned at the point of insertion of the main ear (AFA). Trials were conducted in a randomized block design 5 m row plots. Analyses of variance for disease severity were performed by Gardner and Eberhart's Analysis II, in combination with Griffing's Method 4, Model I. The diallel analysis of environments indicated highly significant environment (E), CGC and CGC x E effects for both evaluation methods; CEC effects significant for PI but not for AFA; interactions CEC x E not significant for both disease severity variables. CGC effects were more important than CEC. This suggests that additive genetic effects are more important as sources of variation for disease resistance in this set of inbred lines. Heterotic effects were found in crossings between resistant lines and between susceptible ones, although in the first case the effects were more evident. Specific hybrid combinations of lines with high potential for the genetic control of this pathogen were identified.

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Published

2001-12-01

Issue

Section

Genetics and Plant Breeding

How to Cite

Combining capacity and heterosis for resistance to Puccinia polysora Underw. in maize . (2001). Scientia Agricola, 58(4), 777-783. https://doi.org/10.1590/S0103-90162001000400020