摘要
为评价从朱红毛斑蛾Phauda flammans幼虫僵虫中分离的虫生真菌在害虫生物防治中的应用潜力,通过形态学鉴定及ITS基因序列分析对分离菌株进行鉴定,并运用时间-剂量-死亡率模型分析该分离菌株对朱红毛斑蛾1~6龄幼虫的毒力。结果显示,结合形态学特征和ITS基因序列分析将该虫生真菌鉴定为球孢白僵菌Beauveria bassiana,并将该菌株命名为Pf Bb。球孢白僵菌Pf Bb菌株可侵染朱红毛斑蛾1~6龄幼虫,随着该菌株孢子液浓度的增加,其对朱红毛斑蛾幼虫的毒力逐渐增强。Pf Bb菌株孢子液处理朱红毛斑蛾1~5龄幼虫6 d时的LC_(50)分别为2.61×10^(4)、1.04×10^(5)、1.11×10^(6)、1.54×10^(6)和1.44×10^(7)个/m L,处理6龄幼虫8 d时的LC_(50)为1.02×10^(7)个/m L。随着处理时间的增加,Pf Bb菌株对朱红毛斑蛾1~6龄幼虫的LC_(50)和LC90随之降低,表明存在剂量效应。当处理浓度相同时,朱红毛斑蛾1~6龄幼虫的僵虫率随着虫龄的增加而降低,但在较高浓度1.0×10^(7)~1.0×10^(9)个/m L处理时,1~5龄幼虫的僵虫率无显著差异,说明1.0×10^(7)个/m L球孢白僵菌Pf Bb菌株孢子液防治朱红毛斑蛾幼虫即可达到理想的防治效果。表明球孢白僵菌Pf Bb菌株对朱红毛斑蛾有较大的生防应用潜力。
To evaluate the biocontrol potential of an entomogenous fungus strain isolated from Phauda flammans larvae,this fungus was identified with morphology and ITS sequence analysis,and the timedose-mortality model(TDM)was used to analyze its virulence to 1st-6th instar larvae of P.flammans.The results showed that this strain was Beauveria bassiana and named as Pf Bb.It could infect 1st-6th instar larvae of P.flammans,and its virulence to P.flammans larvae gradually increased with increasing spore concentrations.The LC_(50)values of Pf Bb against 1st to 5th instar larvae of P.flammans were 2.61×10^(4),1.04×10^(5),1.11×10^(6),1.54×10^(6)and 1.44×10^(7)conidia/m L,respectively,after treated for 6 d,while the LC_(50)value of Pf Bb for the 6th-instar larvae was 1.02×10^(7)conidia/m L after treated for 8 d.The LC_(50)and LC90values of Pf Bb for 1st-6th instar larvae decreased with increasing treatment time,indicating that there was a dose effect.The cadaver rates of 1st-6th instar larvae of P.flammans treated by Pf Bb de-creased with increasing larval instars at the same spore concentration.However,there was no significant difference in the cadaver rates of 1st to 5th instar larvae of P.flammans at higher concentrations(1.0×10^(7)-1.0×10^(9)conidia/m L),which suggested that 1.0×10^(7)conidia/m L of Pf Bb was enough to control P.flam-mans larvae.The results indicated that Pf Bb has a good potential for biocontrol of P.flammans larvae.
作者
陈学敏
高一平
韦继光
王小云
陆温
郑霞林
Chen Xuemin;Gao Yiping;Wei Jiguang;Wang Xiaoyun;Lu Wen;Zheng Xialin(Guangxi Key Laboratory of Agric-Environment and Agric-Products Safety,College of Agriculture,Guangxi University,Nanning 530004,Guangxi Zhuang Autonomous Region,China)
出处
《植物保护学报》
CAS
CSCD
北大核心
2022年第6期1788-1798,共11页
Journal of Plant Protection
基金
国家自然科学基金(31660206)。
关键词
朱红毛斑蛾
球孢白僵菌
毒力
僵虫率
Phauda flammans
Beauveria bassiana
virulence
cadaver rate
