Ombura Fidelis Levi Odhiambo, Malele Imna, Abd-Alla Adly Mm, Akutse Komivi Senyo, Ajene Inusa Jacob, Khamis Fathiya Mbarak
International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya.
Tanzania Veterinary Laboratory Agency, Dar es Salaam, Tanzania.
Insect Sci. 2025 Apr 27. doi: 10.1111/1744-7917.70052.
Glossina austeni Newstead (Diptera: Glossinidae) is a competent vector of the trypanosomes causing human African trypanosomiasis and the African animal trypanosomosis. Management of this pest has primarily involved trapping methods, Sterile Insect Technique, and research into vector competence-symbiotic interactions. Nevertheless, the use of entomopathogenic fungi (EPF) in integrated pest management programs for G. austeni control remains limited. Moreover, different tsetse fly species exhibit varying susceptibility to different EPF strains, indicating that no single strain is universally effective. Therefore, our study aimed to identify candidate EPF isolates for G. austeni management, evaluate the effects of temperature on the radial growth of these potent isolates, and assess the impact of the candidate EPF on the gut microbiome of G. austeni. Consequently, 16 Metarhizium anisopliae (Metschn.) Sorokin isolates were screened against G. austeni using dry conidia in an infection chamber, with the most virulent isolates having LT values of 3.95-9.37 d. Temperature significantly influenced the radial growth, conidia germination, and yield of these strains. There were also significant differences in conidia acquisition, retention and transmission between male and female G. austeni flies. Furthermore, all conidia receivers carried sufficient conidia, 5 d post-interaction with EPF-challenged conidia donors. Microbiome analysis revealed Wigglesworthia, Serratia, Klebsiella, and Escherichia as the most abundant taxa. Among the M. anisopliae isolates, ICIPE 82 exhibited the fastest radial growth and highest thermostability, hence selected as a potential biopesticide candidate for managing G. austeni. This study demonstrates the efficacy and potential of M. anisopliae ICIPE 82 as a biopesticide for controlling G. austeni.
奥氏采采蝇（Glossina austeni Newstead，双翅目：采采蝇科）是传播导致人类非洲锥虫病和非洲动物锥虫病的锥虫的有效媒介。对这种害虫的管理主要涉及诱捕方法、昆虫不育技术以及对媒介能力与共生相互作用的研究。然而，在用于控制奥氏采采蝇的综合害虫管理计划中，昆虫病原真菌（EPF）的使用仍然有限。此外，不同种类的采采蝇对不同的EPF菌株表现出不同的易感性，这表明没有单一菌株具有普遍有效性。因此，我们的研究旨在确定用于管理奥氏采采蝇的候选EPF分离株，评估温度对这些高效分离株径向生长的影响，并评估候选EPF对奥氏采采蝇肠道微生物群的影响。因此，在感染室中使用干燥分生孢子对16株绿僵菌（Metarhizium anisopliae (Metschn.) Sorokin）分离株进行了针对奥氏采采蝇的筛选，毒性最强的分离株的LT值为3.95 - 9.37天。温度显著影响这些菌株的径向生长、分生孢子萌发和产量。奥氏采采蝇的雄性和雌性在分生孢子获取、保留和传播方面也存在显著差异。此外，在与受EPF挑战的分生孢子供体相互作用5天后，所有分生孢子受体都携带了足够的分生孢子。微生物群分析显示，维氏菌属、沙雷氏菌属、克雷伯菌属和大肠杆菌是最丰富的分类群。在绿僵菌分离株中，ICIPE 82表现出最快的径向生长和最高的热稳定性，因此被选为管理奥氏采采蝇的潜在生物农药候选菌株。本研究证明了绿僵菌ICIPE 82作为控制奥氏采采蝇的生物农药的有效性和潜力。
