广东省主栽水稻品种稻瘟病主效抗性基因的鉴定及分析

 利用稻瘟病抗性基因进行抗病新品种的培育是控制稻瘟病害最经济、有效的措施。为了明确当前广东省水稻稻瘟病抗性基因的分布特点,本研究利用Pi1、Pi2、Pi9、Pib、Pita等5个已克隆主效抗稻瘟病基因的分子标记,结合叶瘟和穗颈瘟自然抗性鉴定,对70份广东省主栽水稻品种和骨干亲本抗稻瘟病基因的组成进行了分析。结果显示,含有Pi2抗性基因的水稻品种有10份(占14.3%),抗性贡献率显著;Pib和Pita的检出率较高,分别为42份(60%)和37份(52.9%),但对广东省稻瘟病菌的抗性较弱;未检测到上述已知主效抗稻瘟病基因的有13份(18.6%),表现为感稻瘟病;全部供试材料均未检测到含有Pi1和Pi9抗性基因。本研究揭示了广东省主栽水稻品种和骨干亲本抗稻瘟病基因的组成及其对稻瘟病抗性的贡献,为华南稻区抗病新品种的培育提供重要参考。

Identification and analysis of major resistance genes to Magnaporthe oryzae in main rice varieties in Guangdong Province

The utilization of resistance gene is the most economical and effective measure to control rice blast.To clarify the distribution of blast resistance genes in the 70 major rice cultivars in Guangdong Province,five molecular markers were used to detect 5 cloned genes,Pi1,Pi2,Pi9,Pib and Pita,followed by the detection of leaf blast and neck blast.The results showed a significant resistance (14.3%) contributed by Pi2.Pib and Pita were widely distributed among 42 (60%) and 37 (52.9%) cultivars respectively,but had low contribution to the blast resistance.Other 13 ones (18.6%) have no known resistance genes with susceptibility to M.oryzae.This study revealed the composition of blast resistance genes of main rice cultivars and backbone parents in Guangdong Province and their contribution to blast resistance,providing important reference for the breeding of new rice varieties in south China.