Study On Biology Characteristics And Genetic Diversity Of Beauveria Bassiana On Loxostege Sticticalis L. In Inner Mongolia

This paper researched Beauveria bassiana on Loxostege sticticalis L.which were collection from xinganmeng wulanchabu- Hohhot and Eerduosi city in Inner Mongolia, biological characteristics and genetic diversity were analyzed .the results were as follows:1 Seventeen entomopathogenic fungi named Bb-D01-Bb-D04,Bb-S01-Bb-S06 and Bb-Y01-Bb-Y07 were isolated from disease-infected dead insects. Through morphological identification, Bb-D01—Bb-D04,Bb-S01—Bb-S06 and Bb-Y01—Bb-Y07 were Beauveria bassiana, Beauveria, Moniliaceae, Maniliales, Hyphomycetes, Deuteromycotina. Bioassay results showed that seventeen isolates had biological activity on Loxostege sticticalis L. seventeen Beauveria bassiana were determined as the pathogenic fungus of Loxostege sticticalis L.2 Four kinds of carbon sources, four kinds of nitrogen sources and twelve different ratio were studied using medium. The results indicated that sugar could influence on the growth of mycelium and volume of spores of seventeen isolates in which glucose was the best carbon sources, Inorganic carbon was not utilization completely. In nitrogen sources four kinds of nitrogen sources could be absorption completely, Yeast extract was the best nitrogen sources. The growth of mycelium and volume of spores was the best while C:N=40:8. The growth of mycelium and volume of spores were decided by quantity not that proportion of C and N.3 In this paper, the genetic diversity of 17 Beauveria bassiana collected from 3 different areas in Inner Mongolia was tested using inter-simple sequence repeat (ISSR) markers. The major results were listed as follows:1)15 ISSR locl were selected from 21 ISSR locl respectively considering their reproducllbility and polymorphic rate via PCR amplifications. The optimal reactive conditions were determined for better using these markers.2)With 15 ISSR primers, a total of 90 fragments were amplified, in which the polymorphic rate was 96.67%. Nei's genetic diversity index (H) was 0.4309 and Shannon's information diversity index (I) 0.6106. The cluster analysis of the inter-population genetic differentiation showed that the genetic similarity in the western part and the central region was 0.9897at the highest point whereas the genetic similarity in the eastern part and the western part was 0.9601 at the lowest point.