亚洲柑橘木虱2株高致病力病原真菌菌株的筛选

Screening two entomopathogenic fungal strains with high virulence against Asia citrus psyllid,Diaphorina citri

【目的】筛选对亚洲柑橘木虱Diaphorina citri Kuwayama具有高致病力的真菌菌株,为其微生物农药的研发奠定基础。【方法】测定5株球孢白僵菌Beauveria bassiana(菌株A^E)和5株玫烟色棒束孢菌Isaria fumosorosea菌株(菌株A^E)的生长速率、产孢量以及对木虱若虫的侵染致死率等,并进行比较分析。【结果】5株球孢白僵菌培养10 d后产孢量存在较大差异,A菌株的产孢量最少(7.96×107mL^(-1)),E菌株的产孢量最多(3.78×108mL^(-1)),两者差异显著;在喷施球孢白僵菌孢子1×106mL^(-1)7 d后,对柑橘木虱低龄若虫的致死率与对照差异不显著,以A菌株的致死率最高(78.0%),E菌株次之(77.0%)。5株玫烟色棒束孢菌株培养10 d后,B菌株产孢量最多(6.04×108mL^(-1)),E菌株的最少(6.28×107mL^(-1)),两者差异显著;在喷施玫烟色棒束孢孢子1×106mL^(-1)7 d后,除D菌株外,其他制剂对亚洲柑橘木虱低龄若虫的致死率均显著大于对照,B菌株的致死率最高(81.0%)。【结论】综合考虑产孢量及致病力等指标,球孢白僵菌E菌株和玫烟色棒束孢B菌株是具有良好研发前景的柑橘木虱生物防治高致病力优良菌株。

[ Objective] To screen entomopathogenic fungal strains with high virulence against Asia citrus psyllid （ACP） , Diaphorina citri Kuwayama, and to provide a basis for development of microbial pesticide against ACP. [ Method ] The growth and sporulation rates of five Beauveria bassiana strains numbered A to E and five Isaria fumosorosea strains numbered A to E, and the mortality rates of ACP after infected by these ten fungal strains were investigated. [ Result] The spores quantity of five B. bassiana strains were significantly different after cultured for 10 days, strain E had the largest spores quantity （ 3.78 × 10^8 mL^-1 ） and strain A had the least spores quantity（7.96 × 10^7 mL^-1 ）. There was significant difference of spores quantity between strain E and strain A. There was no significant difference among the mortality rates of 2-3 instar ACP nymphs seven days after the spray of 1 ×10^6 mL^-1B, bsssiana fungal spores, and the highest mortality rate （78.0%） was found in the strain A treatment, followed by the strain E treatment （77.0%）. For five I. fumosorosea strains, the spores quantity after cultured for 10 days, strain B had the highest sporulation rate （6.04 ×10^8 mL^-1 ） and strain E had the least spores quantity（6.28 ×10^7 mL^-1）. There was significant difference of spores quantity between strain B and strain E. The mortality rates of 2-3 instar ACP nymphs seven days after the spray of 1 ×10^6 mL^-1 I. fumosorosea fungal spores were higher than the control group except strain D. ACP infected by strain B had the highest mortality rate（81.0% ）. [ Conclusion ] B. bassiana strain E and I. fumosorosea strain B are considered with high virulence against ACP and can be potentially used for biological control of ACP.