Glover James Paul, Portilla Maribel, Parys Katherine, Allen Clint, George Justin, Reddy Gadi V P
Southern Insect Management Research Unit, United State Department of Agriculture-Agricultural Research Service, Stoneville, MS 38776, USA.
Pollinator Health in South Crop Ecosystems Research Unit, United State Department of Agriculture-Agricultural Service, Stoneville, MS 38776, USA.
Pathogens. 2022 Sep 9;11(9):1028. doi: 10.3390/pathogens11091028.
This is the first study that examined and compared the survival, LC50, and RR50 estimates of Megacopta cribraria F. (Hemiptera: Plataspidae) nymphs and adults that were exposed to two native Beauveria bassiana isolates (Previously codified as NI8 and KUDSC strains) at four concentrations. The greatest reduction in survival and mortality was observed primarily on or after 10 d post-exposure to B. bassiana isolates. Survival of early instars (2nd, 3rd) were not affected by either strains or concentration at 3 d and 5 d post-exposure. Survival of later instars (5th) and adults was significantly reduced when exposed to the KUDSC strain at all concentrations. Comparison of dose−mortality values (LC50) using resistance ratios (RR50) were significantly different between life stages of the kudzu bug for both strains of B. bassiana. The LC50 values showed that kudzu bug adults are more susceptible than any other life stage when exposed to either strain. The KUDSC strain was more pathogenic than NI8 10 d after exposure, but NI8 exhibited significantly higher pathogenicity than KUDSC 20 d after exposure. Our results suggest potential field application of B. bassiana for kudzu bug control and their integration into pest management strategies to suppress them before they cause economic damage to soybean crops.
这是第一项研究,该研究检测并比较了豆龟蝽若虫和成虫暴露于两种本地球孢白僵菌分离株(先前编码为NI8和KUDSC菌株)的四种浓度下的存活率、半数致死浓度(LC50)和半数控制浓度(RR50)。暴露于球孢白僵菌分离株后,主要在暴露后10天及之后观察到存活率的最大降低和死亡率。暴露后3天和5天,早期若虫(第2龄、第3龄)的存活率不受菌株或浓度的影响。当暴露于所有浓度的KUDSC菌株时,后期若虫(第5龄)和成虫的存活率显著降低。对于两种球孢白僵菌菌株,使用抗性比(RR50)比较剂量-死亡率值(LC50)在豆龟蝽的不同生命阶段之间存在显著差异。LC50值表明,当暴露于任何一种菌株时,豆龟蝽成虫比任何其他生命阶段更易受影响。暴露后10天,KUDSC菌株比NI8更具致病性,但暴露后20天,NI8的致病性显著高于KUDSC。我们的结果表明球孢白僵菌在田间控制豆龟蝽方面具有潜在应用价值,并且可以将其纳入害虫管理策略,以便在它们对大豆作物造成经济损害之前对其进行抑制。