小麦抗条锈病已知基因对中国当前流行小种的有效性分析

The resistance evaluation of the Yr genes to the main prevalent pathotypes of Puccini a striiformis f.sp.tritici in China

小麦条锈病是危害我国小麦生产最为严重的病害之一,评价已知抗条锈病基因相对于当前主要流行小种的抗病性对开展预见性抗病育种工作具有重要的指导意义。本研究利用当前流行频率最高的2个小种(CYR32、CYR33)和1个对Yr26基因有毒性的新菌系V26/CM42对已知抗条锈病(Yr)基因的小麦材料分别进行苗期小种抗病性鉴定和成株期病圃抗病性调查,以评估各已知Yr基因在中国抗病育种中的有效性。结果表明,只有3个Yr基因(Yr5、Yr15和Yr61)对当前流行小种和贵22新菌系表现为全生育期抗病性;3个Yr基因(Yr32、YrTr1和YrTye)具有成株期抗病性;此外,Mega、Ibis、Hyak、Maris Huntsman、Hobbit、CarstensV、Express、Lee和Compair等9个含多个Yr基因组合的抗源品种表现出良好的成株期抗条锈性。

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most destructive diseases of wheat in China. To evaluate which resistance genes are still effective to the prevalent pathotypes and to provide the theoretical basis for predictive resistant stripe rust-breeding, we evaluated 73 cultivars with known Yr gene（s） for reaction to the main prevalent stripe rust pathotypes CYR32, CYR33 （Su11-14-3） and isolate V26/CM42 （Pingnan17-5） separately in both the seedling stage and the field test in Yangling and Tianshui. The result showed that the single gene Yr1,Yr2, Yr6, Yr7, Yr8, Yr17, Yr18, Yr21, Yr27, Yr28, Yr29, Yr31, Yr36, Yr39, Yr41, Yr43, Yr44, YrA, YrExp2, YrSP and the Yr-gene combinations in the cultivar Joss Combier, Heines Ⅶ, Heines Peko, Strubes Dikkopf, Capelle Desprez, Stephens, Fielder, Heinese Kolben, Clement, Paha were susceptible in all of the tests, indicating that the genes or gene combinations cannot be used in the practice anymore. The genes Yr10, Yr24 and Yr26 confer race-specific all-stage resistance and are still effective against CYR32 and CYR33 but becoming ineffective to isolate V26/CM42, suggesting that these three genes also cannot be used in the future. Among all the tested single Yr-genes, only genes Yr5, Yr15 and Yr61 had all-stage resistance （ASR） in all the tests, and genes Yr32、YrTr1 and YrTye were resistant in all the field tests in adult stage, but susceptible in at least one test in the seedling stage. These genes showed adult-plant resistance （APR）. Nine cultivars carrying multigene, i.e., Mega, Ibis, Hyak, Maris Huntsman, Hobbit, Carstens V, Express, Lee and Compair also showed APR in this study.