杜鹃属植物内生真菌的分离及对赤拟谷盗和马铃薯腐烂茎线虫的防治作用

Isolation of Endophytic Fungi in Rhododendron and Its Control against Tribolium castaneum and Ditylenchus destructor

本文以千里香杜鹃、头花杜鹃、烈香杜鹃、陇蜀杜鹃4种杜鹃属植物为材料,通过组织分离法分离其内生真菌,测定内生真菌粗提物的抗虫活性,筛选出具有良好抗虫活性的菌株,并对这些菌株进行形态学及分子生物学鉴定,以此初步筛选出对赤拟谷盗和马铃薯腐烂茎线虫具有较好抗虫活性的内生真菌菌株。结果表明:从4种杜鹃属植物中分离得到22株内生真菌菌株,共发酵产生44种粗提物,其中LS-Y-2菌丝体粗提物对赤拟谷盗具有一定触杀活性(LD_(50)=69.31μg/adult);LS-Y-2菌液粗提物、TH-Z-1菌液粗提物和LS-Y-4菌丝体粗提物对马铃薯腐烂茎线虫具有较好杀虫活性,其LC_(50)分别为0.06、0.07、0.18 mg/m L;LS-Y-2菌液粗提物和LS-Y-4菌液粗提物在质量浓度为2 mg/mL时,对赤拟谷盗的拒食率为84.28%和73.12%。通过形态学和分子生物学鉴定发现,LS-Y-2和LS-Y-4属于链格孢属真菌、TH-Z-1属于栓菌属真菌。综上,链格孢属真菌LS-Y-2、LS-Y-4和栓菌属真菌TH-Z-1对赤拟谷盗和马铃薯腐烂茎线虫具有一定防治作用。

Twenty-two strains of endophytic fungi were screened from Rhododendron thymifolium,R.capitatum,R.anthopogonoide,and R.przewalskii using culture isolation method and their insecticidal activities were investigated.The results indicated that crude extracts of LS-Y-2 mycelium showed a better pesticide activity against Tribolium castaneum(LD50=69.31μg/adult),crude extracts of LS-Y-2 fungal liquid showed a good bioactivity against T.castaneum(FDI=84.28%)and Ditylenchus destructor(LC_(50)=0.06 mg/mL),crude extracts of TH-Z-1 fungal liquid showed an obvious pesticide activity against D.destructor(LC_(50)=0.07 mg/mL),crude extracts of LS-Y-4 fungal liquid showed a better antifeedant activity against T.castaneum(FDI=73.12%),crude extracts of LS-Y-4 mycelium showed a better pesticide activity against D.destructor(LC_(50)=0.18 mg/mL).LS-Y-2 and LS-Y-4 belong to Alternaria,TH-Z-1 belong to Trametes.