球孢白僵菌Bb1287菌株对扶桑绵粉蚧毒力的测定

Determination of Virulence of Beauveria bassiana Bb1287 to Phenacoccus solenopsis Tinsley

为明确球孢白僵菌(Beauveria bassiana)Bb1287菌株对扶桑绵粉蚧的侵染能力.采用点滴法测定了球孢白僵菌Bb1287菌株对扶桑绵粉蚧1龄若虫,2龄若虫,3龄若虫和成虫的毒力.结果表明:在2.0×105,2.0×106,2.0×107和2.0×108个/mL 4个浓度的分生孢子液对扶桑绵粉蚧(Phenacoccus solenopsis Tinsley)的若虫和成虫具有很高的毒力.在分生孢子液2.0×108个/mL浓度时1龄若虫,2龄若虫,3龄若虫和成虫的累计校正死亡率分别是(88.52±13.16)%,(83.91±14.04)%,(79.25±9.39)%和(77.39±7.20)%.扶桑绵粉蚧1龄若虫,2龄若虫,3龄若虫和雌成虫的致死中浓度(LC50)分别为(3.2367±0.06)×105,(2.6070±0.06)×106,(3.3943±0.06)×106和(3.4239±0.06)×106个/mL,致死中时间(LT50)分别是(4.09±1.42),(4.70±0.78),(5.28±0.36)和(5.19±0.94)d.得出球孢白僵菌Bb1287菌株对扶桑绵粉蚧的若虫和成虫具有较强的毒力,可作为扶桑绵粉蚧生物制剂开发应用菌株.

Objective： To investigate the infection ability of Beauveria bassiana Bb1287 to Phenacoccus solenopsis Tinsley. Methods：Virulence of B. bassiana strain Bb1287 to 1st instar larvae, 2nd instar larvae, 3rd instar larvae and adults of Ph. solenopsis was measured using topical application. Results： B. bassiana Bb1287 applied at 2.0 × 10^5 , 2.0 × 10^6 , 2.0 × 10^7 and 2.0 × 10^8 spores/mL showed high virulence to the larvae and adults of Ph. solenopsis. The adjusted accumulative mortality rate of the 1st instar larvae, 2nd instar larvae, 3rd instar larvae and adults of Ph. solenopsis was （88. 52 ±13. 16） %, （83. 91 ± 14.04） %, （ 79.25 ± 9. 39 ） % and （77.39 ±7.20） %, respectively, in the treatment of 2.0 ± 10^8 spores/mL. The median lethal concentration （LC50） of the 1st, 2nd and 3rd instar larvae and adults of the pest was （3. 236 7±0.06） ×10^5, （2. 607 0±0.06） ×10^6, （3. 394 3±0.06） ×10^6 and （3. 423 9±0.06） × 10^6 spores/mL, respectively; and the median lethal time （LT50） was （4.09 ± 1.42）, （4.70 ± 0.78）, （5.28 ± 0.36） and （5. 19±0.94） d, respectively. Conclusions： The B. bassiana strain Bb1287 is virulent against the larvae and adults of Ph. solenopsis and can be a potential strain for the development of biological control agents against Ph. solenopsis.