摘要
从烟田烟青虫(Helicoverpa assulta)自然感病虫体上新分离鉴定一株球孢白僵菌Bb062,将其与已有的不同来源地和寄主的10株白僵菌(Beauveria spp.)一起,分别测定其对烟青虫3龄幼虫致病力以及烟青虫3龄幼虫感染高毒力白僵菌后体内保护酶活性的变化。结果表明,在供试的11个白僵菌菌株中,Bb062对烟青虫3龄幼虫毒力最高,10 d累计校正死亡率达91.07%,LT50(致死中时)为4.67 d,且与其他菌株差异显著。以孢子1.0×106、1.0×107和1.0×108个·m L-1悬浮液处理时,烟青虫3龄幼虫累计死亡率随菌液浓度的提高和接菌后时间的延长而增大,LC50(致死中浓度)为孢子1.82×107个·m L-1。烟青虫3龄幼虫感染球孢白僵菌后72 h,其体内超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均表现出先急剧升高,再急剧下降的变化过程。在所测试的菌株中,Bb062菌株对烟青虫毒力最高,且能够显著抑制其体内保护酶活性,因此,该菌株具有作为烟青虫生防菌的应用潜力。
Eleven isolates of Beauveria spp., including B. bassiana （Bb062） newly isolated from Helicoverpa assulta, and other seven B. bassiana isolates and three B. brongniartii isolates that were originally isolated from different geographic origins and various hosts, were tested against the 3rd larvae of H. assulta. Changes of the protective enzyme activity in 3rd larvae of H. assulta infected by a high virulent isolate were also assayed. The results showed that isolate Bb062 had the highest virulence to 3rd larvae among eleven isolates of Beauveria spp., with a corrected mortality reaching 91.07% within 10 days after treatment, and the LT50 value was 4.67 d. After inoculated with 3 concentrations （1.0×106, 1.0×107 and 1.0×108 conidia·mL-1） of Bb062 conidial suspension, the accumulative mortality of the H. assulta larvae increased with an increase of concentration and observation time, and the LC50 value was 1.82×107 conidia·mL-1. Activities of superoxide dismutase, peroxidase and catalase in H. Assulta larvae were rapid increased then dropped sharply within 72 h. Bb062 had a high virulence to H. assulta and could inhibit activities of protective enzymes, so it will be a promising biocontrol agent against H. assulta.
出处
《安徽农业大学学报》
CAS
CSCD
北大核心
2017年第6期1119-1123,共5页
Journal of Anhui Agricultural University
基金
贵州省烟草公司贵阳市公司重大专项(2016-06)
安徽省高校自然科学基金(03087060)
中国烟草总公司山东省公司面上项目(KJ20170413)
中国烟草总公司四川省公司重点科技项目(SCYC201703)共同资助
国家烟草行业烟草病虫害监测与综合治理重点实验室项目(IPM-201411)
关键词
烟青虫
白僵菌
毒力
保护酶
Helicoverpa assulta
Beauveria spp.
virulence
protective enzymes
