中国松干锈病病原菌的种间及种内同工酶变异

从我国不同地区、不同松树上采集代表ＣｒｏｎａｒｔｉｕｍｒｉｂｉｃｏｌａＣｆｌａｃｃｉｄｕｍ及Ｃ。ｑｕｅｒｃｕｕｍ３种松干锈菌的５８个菌株，分析了其种间及种内的同工酶变异。电泳检测过的１３种酶中有８种显出酶带，其中酯酶（ＥＳＴ）同工酶谱具最显著而稳定的种间差异，可作为区别鉴定３种松干锈菌的有效手段。在来自东北各地红松上的１６个Ｃ．ｒｉｂｉｃｏｌａ菌株中未发现任何酶谱变异，显示了本菌群体遗传性质的均一。来自东北地区樟子松上的１７个Ｃｆｌａｃｃｉｄｕｍ菌株中存在酶谱变异，但多数菌株的酶谱同来自安徽及陕西马尾松上的菌株完全一致，此结果支持把我国的Ｃｆｌａｃｃｉｄｕｍ看成一个集合种。来自我国南北不同地区不同松树的Ｃｑｕｅｒｃｕｕｍ菌株，除樟子松上的部分菌株外，其酶谱完全相同，尚未分化出北美的那种专化型间的酶谱差异，可能暗示我国松瘤锈菌的起源晚于北美。

ISOZYMIC VARIATION AMONG AND WITHIN SPECIES OF PINE-STEM RUST FUNGI IN CHINA

Fifty-eight isolates representing three Cronartium species, the pine-stem rust fungi, collected from diverse pine hosts and geographic origins in China were evaluated for their interspecific and intraspecific variation by isozyme analysis. Eight of the 1 3 examined enzymes produced visible banding patterns. Among them the esterase (EST) patterns provided the best differentiation , distinctly seperating C. ribicola, C .flaccidum and C quercuum from one another. No isozymic variants were detected in the 1 6 C. ribicola isolates from different locations in northeastern China, demonstrating that the genetic variation in the population of this rust fungus in this area is small. Although some variants were found in the 1 7 C quercuum isolates from mongolian pine in northeastern China, the isozyme patterns of the majority of the isolates, however, were uniform with those of the isolates from Masson's pine in eastern and central China, indicating the validity of considering .C flaccidum occurring in China as a complex species. Nineteen C quercuum isolates collected from diverse hosts and loca-tions in northeastern , eastern and central China, except some of those from mongolian pine, also provided uniform isozyme patterns and did not show the isozymic variability as big as that previously reported in northern American C. quercuum Population, possibly implicating the occurrence of C quercuum in China is a more recent event than that in northern America .