中国东部栗疫病菌群体的遗传分化*

本实验采用RFLP技术,对中国东部栗疫病菌(Cryphonectria parasitica)进行了群体遗传结构的研究。313个参试菌株来自10个省(市)的16个群体(子群体),样本分布在北纬24°N—41°N。各菌株的DNA分别用限制性内切酶Pst Ⅰ和EcoR Ⅰ酶切,先后以10个低拷贝DNA探针和1个DNA指纹图谱探针进行了杂交和检测。结果表明,两个探针(pCB29和pMS29.1)的杂交图谱呈单态性;探针pCB19的杂交图谱显示,菌株DNA以PstⅠ酶切的为单态性,以EcoR Ⅰ酶切的则呈多态性;其他7个低拷贝探针的杂交图谱都呈多态性(Pst Ⅰ酶切)、指纹图谱探针的检测结果显示,辽宁凤城群体的菌株与中国东部其他群体的菌株相比,具有更多的限制性杂交片段,菌株间的遗传变异性也更大。

GENETIC DIVERSITY IN THE POPULATIONS OF CRYPHONECTRIA PARASITICA FROM EASTERN CHINA

We studied genetic diversity in populations of the chestnut blight fungus, Cryphonectria parasitica, from eastern China, using restriction fragment length polymorphisms (RFLPs). 313 isolates were collected from 16 populations in Guangdong, Hunan, Fujian, Jiangxi, Zhejiang, Jiangsu, Anhui, Shandong, Beijing and Liaoning provinces, representing areas from 24 °N to 41 °N latitude. DNA from each isolate was digested separately with the restriction endonucleases Pst I and EcoR Ⅰ, and then probed with 10 low-copy, nuclear probes and a fingerprinting probe (pMS 5. 1). Two probes (pCB 29 and pMS 29. 1) were monomorphic. Probe pCB 19 was monomorphic with Pst I but poly-morphic with EcoR Ⅰ. The other 7 low-copy probes were polymorphic with Pst Ⅰ. The fingerprinting probe showed more restriction fragments and much greater variability among the isolates from Fengcheng population than that from the other populations in eastern China.