绿僵菌航天诱变菌株的DNA变异性分析

昆虫病原真菌绿僵菌M2189菌株经航天搭载诱变后,分离得到200多个单孢菌株。以9个随机引物对47个诱变菌株进行PCR扩增,获得了38个位点的共1381条DNA片段。统计分析表明,47个诱变菌株在DNA水平上发生了不同程度的变异,变异系数在0.062~0.406之间,平均为0.176,>0.3的有3个菌株。由聚类分析可将47个诱变菌株划分为14个组群,组间变异率小于0.2,与原始菌株相比变异系数接近的诱变菌株无规律地分散在不同组群中,说明航天诱变导致DNA变异的位点和频率是随机的、分散的,并无特定位点。航天诱变为选育生物防治优良菌株提供了新途径。

DNA VARIABILITY ANALYSIS OF SPACE INDUCED METARHIZIUM ANISOPLIAE

Metarhizium anisopliae M2189, an effective entomopathogenic fungal strain, was boarded on a spacecraft aviating at the height of 200 - 350km for 18d. After landing, single spores of the strain were inoculated on PDA medium supplemented with 1% peptone, and more than 200 isolates were obtained. 47 isolates were analyzed in respect of DNA variability based on PCR by 9 random primers. Results showed that 1381 DNA fragments were obtained at 38 sites. Their variant coefficients of DNA polymorphism relative to initial strain were in the range of 0.062 - 0.406, mostly at 0.1 - 0.3 and 0. 176 averagely. Three mutants had over 0.3 variant coefficients among the mutated isolates. Cluster analysis could divide the 47 isolates into 14 groups, on 0.2 variant coefficients between the groups. Those isolates with less variant coefficients were distributed in different groups. It was indicated that aerospace mutation would affect DNA at random sites. Aerospace mutation could be used as to obtain new entomopathogenic strain for biological control.