VIEW ARTICLE

Genetics

Inheritance of Resistance to Blast in Some Traditional and Improved Rice Cultivars. Z. H. Yu, Former research scholar, International Rice Research Institute, P.O. Box 933, Manila, Philippines; D. J. Mackill, and J. M. Bonman. Associate plant breeder, and Associate plant pathologist, International Rice Research Institute, P.O. Box 933, Manila, Philippines. Phytopathology 77:323-326. Accepted for publication 13 June 1986. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/Phyto-77-323.

Rice blast, caused by Pyricularia oryzae, is one of the most destructive rice diseases. Information on the inheritance of blast resistance is useful in breeding resistant cultivars. Five improved and four traditional cultivars were evaluated for the genetics of resistance to three Philippine isolates of P. oryzae. Complete isolate-specific resistance was generally controlled by one or two dominant genes. A recessive gene controlled resistance in IR54 against one isolate. Linkage analyses showed that resistance to different isolates was conditioned by genes at different loci. At least seven genes conditioned resistance to the three isolates. Linkage between genes for resistance to different isolates was detected.