四川省杂交稻主栽品种抗稻瘟病基因型推导研究

Genotyping of Resistance to Blast Disease in Hybrid Rice from Sichuan Province

本文对包括131个杂交稻品种在内的134个四川省水稻主栽品种接种了21个对已知抗稻瘟基因具鉴别力稻瘟病菌株,根据比较各品种和含已知抗瘟单基因系对鉴别菌株的抗谱对各主栽品种进行了抗稻瘟病基因型推导。结果表明,134个参试品种中,仅红优44和泸优1号对全部21个鉴别菌株的抗感反应完全一致;通过DPS统计软件对各品种的抗谱进行聚类分析,在相似距离为0.8时可将这些品种的抗性基因型划分为7个类群;应用基因型推导软件分析,推导出D香287可能携带Pi-km、Pi-zt和Pi-7等3个抗性基因,Q优2号则可能携带Pi-k、Pi-I、Pi-t和Pi-19等4个抗性基因,其余品种则均可能携带未知抗病基因。各品种在病圃中的最高叶瘟级别和平均颈瘟率与其对21个鉴别菌株的抗病频率呈显著负相关(P<0.01)。

In this paper, the genotypes of the resistance to blast disease in 134 commercial rice varieties, of which the majority were hybrid rice, were postulated by inoculating 21 differentiated isolates of M. oD,z.ae of different compatible spectra to 21 lines of which each had a sin＊ gle known resistance gene. The result showed that only 2 out of the tested accessions, i. e, Lu You No. 1 and Hong You 44 showed the same compatible spectra to the 21 differentiating isolates. The cluster analysis of the compatible spectra of the tested varieties resulted in 7 groups when the similarity index computed by DPS software was at 0. 80. The genotypes of 2 hybrid rice, D Xiang 287 and Q You NO. 2 could be clearly postulated. The former probably contained Pi-k^m ,Pi-x^2 and Pi-7 and the latter were considered to contain Pi-k, Pi-l, Pi-t and Pi-19. Unknown resistant genes were found to be present in all of the other varieties. The resistance frequencies to the 21 differential isolates of 134 accessions were negatively correlated to their available severity scores of leaf blast symptoms and average percentage of the disease ear necks （P〈0.01）.