Institute of Biological Control, College of Plant Protection, Jilin Agricultural University, Changchun, China.
Department of Entomology, Abdul Wali Khan University, Mardan, Pakistan.
J Econ Entomol. 2022 Jun 8;115(3):731-738. doi: 10.1093/jee/toac031.
The whitefly, Bemisia tabaci (Gennadius), is a key pest of many economically important crops grown in the field and in greenhouses throughout the world. Because entomopathogenic fungi (EPF) are potential biological control agents for B. tabaci, however, minimal research has been conducted on using fungal strains to control B. tabaci. In this study, four EPF strains were isolated and identified as Lecanicillium attenuatum (Zare & Gams) JL-003, Beauveria bassiana Balsamo (Vuillemin) JL-005, Lecanicillium longisporum (Petch) JL-006, and Akanthomyces lecanii (Zimmerman) JL-007, based on rDNA-ITS sequence analysis. In comparing the virulence of the four fungi against the different life stages (i.e., eggs, 1st-, 2nd-, 3rd-, 4th-instar nymphs, and adults) of B. tabaci the mortality of B. tabaci decreased and LT50 values increased as the conidia concentration decreased in a series of conidia concentrations (1 × 105, 106, 107, and 108 conidia/mL). The fungal strains L. attenuatum JL-003 (LC50: 1.31 × 106) and B. bassiana JL-005 (LC50: 0.92 × 106) were found to be more effective than L. longisporum JL-006 (LC50: 4.97 × 107) and A. lecanii JL-007 (LC50: 6.46 × 106). Fourth-instar nymphs, eggs, and adult stages of B. tabaci were less susceptible to all fungal strains compared to 1st-, 2nd-, and 3rd-instar nymphs. The virulence of L. attenuatum, which was tested for the first time on B. tabaci, was found to be more toxic to early-stage nymphs. Our data will be useful in biological control programs that are considering using EPF against B. tabaci.
烟粉虱，Bemisia tabaci（Gennadius），是全世界田间和温室中许多重要经济作物的关键害虫。然而，由于昆虫病原真菌（EPF）是烟粉虱的潜在生物防治剂，因此对利用真菌菌株来控制烟粉虱的研究很少。在这项研究中，根据 rDNA-ITS 序列分析，从分离并鉴定了 4 株 EPF 菌株，分别为 Leacanicillium attenuatum（Zare & Gams）JL-003、Beauveria bassiana Balsamo（Vuillemin）JL-005、Lecanicillium longisporum（Petch）JL-006 和 Akanthomyces lecanii（Zimmerman）JL-007。在比较了这 4 种真菌对烟粉虱不同生活阶段（即卵、1、2、3、4 龄若虫和成虫）的毒力时，随着一系列孢子浓度（1×105、106、107 和 108 个孢子/mL）的降低，烟粉虱的死亡率降低，LT50 值增加。菌株 L. attenuatum JL-003（LC50：1.31×106）和 B. bassiana JL-005（LC50：0.92×106）比 L. longisporum JL-006（LC50：4.97×107）和 A. lecanii JL-007（LC50：6.46×106）更有效。与 1、2 和 3 龄若虫相比，4 龄若虫、卵和成虫阶段的烟粉虱对所有真菌菌株的敏感性较低。首次在烟粉虱上测试的 L. attenuatum 的毒力被发现对早期若虫的毒性更大。我们的数据将有助于那些正在考虑使用 EPF 对抗烟粉虱的生物防治计划。
