关键词: 白叶枯病, 菌系, 抗性, 遗传, 基因效应

Abstract: The inheritance and gene effects for resistance to bacterial blight Xanthomonas oryzae pv. oryzae in four rice varieties were analyzed by bi-parental backcrossing design. The inheritance of resistance to two strains (typeⅡ: KS-6-6 & type Ⅳ: Zhe 173) was found to be incompletely recessive, which was in good conformity with the additive-dominance model by the individual scaling test; additive effects were highly significant but not the dominance and epistatic effects. The additive genetic variation contributes most to the total although both additive and dominance variations were present, as were shown by the higher heritabilities in both broad sense and narrow sense. A highly significant positive correlation found between the disease scores of strains (Ⅱ and Ⅳ ) indicated that they are non-independently inheritant. It was inferred that the resistance to both strains of bacterial blight in the resistant variety, Jia 23, is characteristic of quantitative inheritance of incomplete recessiveness which may be controlled by a set of multiple genes, and at least one pair of recessive genes in terms of the effective factors is shown to play the leading role in the varieties studied. Implication of screening and selective breeding of resistant rice lines was also discussed.

Key words: bacterial blight, gene effects, inheritance, resistance, pathogenic strain