野生麦角调查研究(续)

根据国内现有资料统计,目前已发现的麦角菌有Claviceps purpurea(Er.)Tul.,C.microcephala(Wall.)Tul.,C.paspali Stev.er Hall.,C.miscanthi Saw.以及C.syntherismae Saw.等5个种;已发现的寄主植物有35属70种,分别属于禾本科及莎草科。总计禾本科植物内共有麦角菌寄主植物34属69种;莎草科仅有1属1种为Carex subpediformis(Kük)Suto et Suzuki。无论是在东北或是华北地区,寄生在拂子茅或披碱草上的麦角,其含碱量都是比较高的,两者的含碱量分别为0.405—0.56%及0.30—0.33%,相反地,寄生在黑麦上的麦角含碱量一致是低的,其麦角含碱量仅达0.06—0.065%。影响麦角碱含量高低的主要原因是麦角菌不同生态类型产碱能力的差异;寄主植物也有一定影响。历来麦角菌Claviceps purpurea及C.microcephala的分类标准,都是以子座头大小来区别的。但根据我们的观察,子座头的大小,并不是固定不变的特征。因此,以子座大小作为麦角菌分类的标准并不完全可靠。

A FURTHER STUDY OF WILD ERGOTS IN CHINA

Wide distribution and abundant production of wild ergots had been reported in China and many collections proved valuable because of their relatively high contents of alkaloids. According to informations so far available, 5 species of ergot were recorded, namely, Claviceps purpurea (Fr.) Tul., C. microcephala (Wallr.) Tul., C. paspali Stev. Hall., C. miscanthi Saw., and C. syntherismae Saw. Of the 70 recorded host species which were distributed in 35 genera, only one species (Carex subpediformis (Kuk) Suto et Suzuki) belongs to Cyperaceae; the rest are all Gramineal, with 13 genera including 33 species distributed in the subfamily Poaeoidae, 9 genera including 19 species distributed in Agrostoideae, 13 genera including 17 species in Panicoideae. None were found in the subfamily Oryzoideae.In Poaeoideae, 25 host species of 9 genera belong to Hordeae, a tribe with largest number of host species; the tribe Agrostideae of Agrostoideae comes next, possessing 19 host species of 8 genera. Regardless of different localities (North and Northeast China), the alkaloid contents of ergot collections from Calamagrostis epigeios and Clinelymus dahuricus were relatively high (0.405—0.56% and 0.30—0.33% respectively).On the other hand, the alkaloid content of rye ergots was rather low (0.06—0.065%). Variations of alkaloid contents due to different localities as well as different years appeared inconspicuous. Consequently, genetic capability of ergot races appeared to be the major factor resposible for alkaloid content, while host species may also have considerable influence. C. microcephala is conventionally distinguished from C. purpurea by the size of perithecial stroma. However, it is apparent in our experiments that this is not a valid criterion because of its extreme variability. As a matter of fact, stromatal size varies proportionally with the size of Sclerotium which in turn is dependent on the size of host seeds. When these two organisms were inoculated to the same host species (rye for instance), the size of stromata of the resultant sclerotia showed virtually no conspicuous difference.Therefore, C. microcephala should not be differentiated from C. purpurea.