USDA APHIS PPQ S&T Insect Management & Molecular Diagnostics Laboratory, Edinburg, TX, USA.
University of Texas Rio Grande Valley, Center for Vector-Borne Diseases, Edinburg, TX, USA.
J Econ Entomol. 2022 Feb 9;115(1):56-64. doi: 10.1093/jee/toab229.
The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vectors 'Candidatus Liberibacter spp.', the causative agent of Citrus Greening Disease (CGD) or Huanglongbing (HLB). Managing populations of psyllids in the Lower Rio Grande Valley (LRGV), TX, United States is imperative given a continuous increase in HLB-positive trees. A component of integrated pest management (IPM) program is the use of strains of entomopathogenic fungi for the biological control of D. citri. In an attempt to find endemic strains of entomopathogenic fungi that grow favorably under LRGV environmental conditions and naturally infect D. citri, psyllids were collected from local residential areas, surface sterilized, and plated on a semi-selective agar medium. Collection of over 9,300 samples from 278 sites throughout the LRGV led to the positive identification of two Beauveria bassiana (Balsamo-Crivellii) Vuillemin (Hypocreales: Cordycipitaceae) isolates, ACP18001 and ACP18002. Chi-square analysis of primary and secondary acquisition bioassays revealed that both field isolated strains outperformed Cordyceps (Isaria) fumosorosea (Wize) (Hypocreales: Cordycipitaceae) Apopka97 under both primary (direct spray) and secondary acquisition (adult exposure to sprayed foliage) bioassays with ACP18002 marginally outperforming ACP18001 under secondary acquisition. Slopes of the dose response regression lines for the three fungi were not significantly different. In addition, the thermal profiles for vegetative growth of each isolate indicated that the field isolates grew at higher rates than the standard at higher temperatures. The new isolates may prove to be good candidates for the management of D. citri populations in the LRGV.
亚洲柑橘木虱（ACP），Diaphorina citri Kuwayama（半翅目：丽花科），传播“候选自由杆菌属 spp.”，是柑橘黄龙病（CGD）或黄龙病（HLB）的病原体。考虑到 HLB 阳性树的持续增加，管理美国得克萨斯州下里奥格兰德河谷（LRGV）的木虱种群至关重要。综合虫害管理（IPM）计划的一个组成部分是利用昆虫病原真菌的菌株进行 D. citri 的生物防治。为了寻找在 LRGV 环境条件下生长良好并自然感染 D. citri 的地方病原真菌菌株，从当地居民区采集木虱，进行表面消毒，并在半选择性琼脂培养基上进行平板培养。从 LRGV 278 个地点收集了超过 9300 个样本，从中鉴定出了两个球孢白僵菌（Balsamo-Crivellii）Vuillemin（Hypocreales：Cordycipitaceae）分离株，ACP18001 和 ACP18002。初级和次级获得生物测定的卡方分析表明，这两个田间分离株在初级（直接喷雾）和次级获得（成虫暴露于喷雾叶）生物测定中均优于拟青霉（Isaria） fumosorosea（Wize）（Hypocreales：Cordycipitaceae）Apopka97，而 ACP18002 在次级获得中略优于 ACP18001。三种真菌的剂量反应回归线斜率没有显著差异。此外，每个分离株的营养生长热谱表明，田间分离株在较高温度下的生长速度高于标准。新的分离株可能是管理 LRGV 地区 D. citri 种群的良好候选者。
