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作 者 ：夏滔,李佼佼,李强,李高宝,王芳,康振生，王保通

期 刊 ：植物病理学报 2012年 42卷 6期 页码：594-599

关键词：小麦条锈菌；T4新菌系；寄生适合度；

Keywords:T4 new strains of Puccinia striiformis f.sp.tritici, parasitic fitness,

摘 要 ：为预测T4新菌系在我国未来小麦条锈菌的流行趋势，本研究以高感品种铭贤169为试材，以我国条锈菌5个主要流行小种（菌系）CYR29、CYR31、CYR32、CYR33、Su11-4为对照，采用主成分分析法测定了T4新菌系的寄生适合度。结果表明：在供试菌系范围内，决定其寄生适合度属性的3个主成分依次为条锈菌的侵染能力、扩展能力和产孢能力(繁殖力)；通过建立数学模型计算供试菌系的侵染能力、扩展能力和产孢能力，结果表明：CYR33和CYR32相对寄生适合度较高，Su11-4的寄生适合度居中，CYR31及CYR29其寄生适合度较低，而感染“中四”苗期的新菌系T4，相对寄生适合度最低。结合该菌系对我国目前推广品种和后备品种致病性和毒性结果分析，该菌系在今后一段时间内不会成为我国小麦条锈菌的优势菌系。

Abstract:In order to predict the future populations of T4 new strains of Puccinia striiformis f．sp．tritici in China，the Mingxian 169 was used as the host to estimate the parasitic fitness. The results showed that the infectivity (represented by number of colonies) contributed to the most important portion in parasitic fitness，and the next two important characters for rust fungal parasitic fitness were spread capacity and sporulation capacity．Germination ability didn‘t show significant difference among the tested races．The mathematical models had been used to estimate three principal components：infectivity，spread capacity and sporulation capacity．According to these models，the relative parasitic fitness of isolates CYR32 and CYR33 was higher than that of other tested races and had already been the predominant races at the present time．Isolate Su11-4 was in the middle. Isolate CYR31 and CYR29 showed lower parasitic fitness，their occurrence frequency had been decreasing recent years and becoming secondary race．Also，for the lower parasitic fitness, the new pathogenic type T4 infected the seedling of differential host ‘Zhong 4’couldn’t become the prevalent race in the bear future．

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