大麦白粉菌种群毒性监测及抗性材料鉴定

2005和2006年从我国冬大麦区采集和分离大麦白粉菌单胞菌株729个,利用Pallas近等基因系进行致病型鉴定和群体毒性频率分析.同时,利用分离得到的不同致病型菌株,通过抗谱分析的方法鉴定了328份大麦品种(系)的白粉病抗性和抗病基因.结果显示:大麦白粉菌群体对抗病基因Mlal Mla(A12)、Mla3、Mla6 Mla14、Mla7 Mla(No3)、Mla7 Ml(Lg2)、Mla9 Mlk、Mla9、Mlal3 MlaRu3、Mlpl、Mlg(Cp)和mlo5的毒性频率为0;对Mla12 MlaEm2、Mla7 Mlk、Mlat Mla8、Mla10MlaDu2和Mlk1的毒性频率很低,分别为0.1%、0.4%、0.9%、2.8%和4.2%.两年共鉴定出不同的致病型21个,致病型000、001和003在两个年度皆为优势致病型.所鉴定的328份材料绝大多数感病,仅37份抗病材料,能明确推导出抗白粉病基因的品种(品系)很少,这些品种(品系)含有的抗白粉病基因为Mr(Bw)Mla8、Mlg、Mira Mla8、Mla9 Mla1、Mla Mla(A12)和mlo5.

Investigation on virulence of Blumeria graminis f.sp.hordei population and resistance to powdery mildew of barley varieties

Pallas isogene lines possessing known barley powdery mildew (Blumeria graminis f.sp.hordei) resistant genes were used in virulence analysis for the population consisted of 729 isolates collected from the Winter Barley Region of China in 2005 and 2006, and more, resistance and resistance genes to powdery mildew in 328 barley varieties (lines) were identified. All isolates were avirulent to Mla1 Mla(A12), Mla3, Mla6 Mla14,Mla7 Mla(No3), Mla7 Ml(Lg2), Mla9 Mlk, Mla9,Mla13 MlaRu3, Mlp1, Mlg(Cp) and mlo5, and the frequencies of isolates overcoming the genes Mla12 MlaEm2 (0.1%), Mla7 Mlk (0.4%), Mlat Mla8 (0.9%), Mla10 MlaDu2 (2.8%) and Mlk1 (4.2%) were very low. Twenty-one pathotypes were found from the examined populations, and pathotypes 000, 001 and 003 were dominant. Almost all of 328 varieties (lines) tested were susceptible to powdery mildew, but 37 of these were resistant to all dominant pathotypes. Resistance genes can be postulated in less of the varieties (lines) investigated positively, the resistance genes, included in these varieties (lines) were Ml(Bw) Mla8, Mlg, Mlra Mla8, Mla9 Mlk, Mla1 Mla(A12) and mlo5.