细脚拟青霉不同菌株间的菌丝联结现象观察及其毒力测定

用 Giemsa 染色观察了细脚拟青霉(Paecilomyces tenuipes)803和1401菌株间的菌丝联结现象,观察了菌丝、孢子的细胞核数目。孢子均是单核,菌丝细胞有1—2个核,多数为单核,菌丝尖端有1—6个核。毒力测定结果表明:能形成异核体的亲和单孢子菌株组合803-17和1401-9、803-3和1401-8的混合培养物毒力与未经培养的相同菌株组合的菌丝体混合物毒力显著不同。在讨论申提出这种差异的原因是:在 Sm 液体培养中,混合接种803-17和1401-9、803-3和1410-8,经11天的混合培养后,混合培养物中形成了与核体亲本菌丝(803-17、1401-9、803-3、1401-8)毒力显著不同的异核菌丝体(803-17×1401-9)、(803-3×1401-8)。

OBSERVATION OF HYPHAL ANASTOMOSIS BETWEEN DIFFERENT FIELD ISOLATES IN PAECILEMYCES TENUIPES AND DETEMINATION OF THEIR VIRULENCE

The hyphal anastomosis between the monoconidial culture of isolates 803 and 1401 in Paecilornyces tenuipes was observed.Fixed and stained mycelium was examined microscopically in order to observe the anastomosing hyphae with·stained nuclei and to de- termine the variation in the numbers of nuclei in different cells.The conidial cell is uni- nucleate.The number of nuclei in the hyphal tip cells varied from 1 to 6.The number of nuclei in the hyphal cells varied 1 to 2,the majority of cells having one. 803-17 (monoconidial culture of isolate 503) and 1401-9 (monoconidial culture of isolate 1401) which can form heterokaryon were inoculated in Sm liquid medium.After mixed cul- tivation for 11 days,anastomosis between hyphae of 803-17 and 1401-9 was formed;and its pathogenicity on Pieris rapae L.was found to be significantly different from that of the ma- terial physically-mixed with mycelium 803-17 and mycelium 1401-9 (803-17 and 1401-9 are cul- tivated separetely and mixed just before the virulence tests).In discussion it was suggested that the reason for the difference that during mixed cultivation 803-17 and 140109 form hetero- karyon (803×1401-9) whose virulence is significantly different from that of homokaryon parents (803-17;1401-9). The same applies to 803-3 and 1401-8.