我国北方11省（区）、直辖市小麦白粉病菌寄主范围研究

 对采自我国北方11个省（区）、直辖市的65个市、县，小麦近缘野生植物8属42种393份，用小麦白粉病菌11个小种的混合菌种进行接种，除21份免疫外，均接种成功。用接种成功的7属40种共286份小麦近缘植物产生的白粉病菌，分别对小麦回接，亦全部回接成功。用6个小麦白粉病菌小种，对7属15种共29份小麦近缘植物进行分小种接种，发现它们与在小麦上一样有很强的寄生专化现象。在1～6叶期，84.4%的小麦近缘植物对小麦白粉病菌的感病性随生育期的推移而下降，其中47.4%病情降为0,37.0%部分病情下降，15.6%病情变化不大。

THE STUDY ON THE HOST RANGE OF WHEAT POWDERY MILDEW IN THE NORTHERN 11 PROVINCES (REGIONS AND CITIES)

The host range of wheat powdery mildew was studied during the past three years.393 wild wheat relative plant entries classified into 421 species of eight genera were collected from 65 counties of the northern 11 provinces(autonomous regions and municipalities directly under the Central Government).The wild species were inoculated with a mixture of 1 1 physiological races of wheat mildew.The result showed that the inoculation was all successful apart from 21 immune entries.The mildew spores collected from 286 wild plant entries belonging to 40 species of seven genera were inoculated back to a susceptible wheat cultivar Jing Shuang 16 , respectively. The inoculations were all successful.The obvious parsitic specificity was observed as in wheat when six wheat mildew races were inoculated to 29 entries of wild plants belonging to 15 species of seven genera, which had successful colonization for wheat mildew.The susceptibility of 84.4%wild plant entries decreased with the elongation of the growth period during 1-6-leaf stage. Among them ,the reaction type of 47.4%entries became 0, of 37.0% decreased and of 15.6% sustained.