2012年我国部分麦区小麦白粉菌群体对温度敏感性研究

The sensitivity of population of Blumeria graminis f.sp.tritici isolates to temperature in 2012

采用小麦离体叶段法,设置18、22、23、24、25和26℃共6个温度处理,对2012年采集的小麦白粉菌样分离得到的139个单孢堆菌株的温度敏感性进行了测定,这些菌样分别采自于四川、北京、甘肃、河南、浙江、陕西、青海、山东、新疆和云南10省(市、区)。结果表明:供试的139个菌株平均ET50为23.14℃,其中ET50最高为24.46℃,最低为21.34℃;58.76%的供试菌株ET50值在23℃和24℃之间,仅有2.03%的供试菌株的ET50≥24℃。对供试菌株温度敏感性频率分布的正态检验结果发现,自然环境中小麦白粉病菌群体已受到温度的选择压力。此研究结果可为了解和预测全球气候变暖对小麦白粉病长期发生趋势的影响提供依据。

The sensitivity of 139 isolates of Blumeria graminis f. sp. tritici to temperature was tested by using detached leaf segment method at 6 different temperatures which were 18,22,23,24,25 and 26 ℃, respectively. These isolates were sampled from 10 provinces or cities such as Sichuan, Beijing, Gansu, Henan, Zhejiang, Shaanxi, Qinghai, Shandong, Xinjiang and Yunnan in 2012. The results showed that the meanET50 of tested isolates was 23.14 ℃. The highest and the lowest ET50 of isolates were 24.46 and 21.34 ℃, respectively. ET50 values of 58.76% isolates were between 23 ℃ and 24 ℃, only 2.03% isolates were higher than 24 ℃. The results of frequencies distribution of ET50 values of the isolates with different sensitivity to temperatures revealed that the pathogen population in natural environment had been selected by temperature pressure. These results will provide basis for predicting effects of global climate change on wheat powdery mildew.