【摘要】 将四川各地小麦白粉菌群体中代表主要毒力基因型（v₁,v₅）的10个菌株,分别接种在25个小麦品种上,考察苗期的相互作用,并在田间病圃对各品种成株期的发病进行观察。结果表明,Pm2x、Pm4抗白粉病基因是高效的;含有Pm2Pm6和Pm2Mld抗性基因组合的品种,苗期对部分供试菌株无效,但成株期平均侵染系数较小,显示有一定的抗性;大多数菌株在含Pm3a抗性基因品种的苗期都能致病,但成株期发病均轻;而含有Pml、Pm3b、Pm3c、Pm5、Pm8、PmlPm2Pm9等基因和基因组合的品种,都有较高的易损性。抗性基因未鉴定的黔丰、黔花系统,肯贵阿、贵光1—2、燕小黑1—1、81夏—51l、81—7241等品种,无论在苗期或成株期对白粉病的抗性都很强。本文还就Pm2和Pm2x抗性基因对白扮菌不同菌株出现的侵染型差异以及抗性基因累加问题进行了讨论。更多还原

【Abstract】 Pathogen-host interaction between 10 wheat powdery mildew isolates from various places representing the elementary prevailing virulence gene combination （v₁, v₅）in Sichuan and 25 wheat varieties carrying various resistance genes either known or unidentified were studied with artificial inoculation both at seedling and adult stages. Gene Pm2x and Pm4 were highly effective in mildew resistance. Varieties possessing the combinations of Pm 2 and Pm6, or Pm2 and Mld showed a rather Small value of average coefficient of infection at adult stage, though they showed high reaction to several mildew isolates at seedling stage. The variety carrying gene Pm3a was susceptible to most of the mildew isolates tested at seeding stage. Low disease incidence, however, had been observed at the adult stage during the past three years. Genes Pm1, Pm3b, Pm3c, Pm5 and Pm8, and the gene-combinations of Pm1, Pm2 and Pm9 were very vulnerable in facing the infection of all the mildew isolates tested. Varieties possessing the unidentified resistance genes such as Qianfeng series and Qianhua series, Ken-Gui-A, Gui-guang 1—2, Yan-Xiao-hei 1—1, 81 Xia-511, 81-7241 all exhibited high resistance both at the seedling and adult stages. Different infection types were observed among varieties carrying the gene Pm2 or the gene Pm2x, and the problem of pyramiding of resistance genes was also discussed.更多还原