Nyahe Patricia Akua Sitsofe, Eziah Vincent Yao, Al-Ani Laith Khalil Tawfeeq, Akumyoungta Monica, Coombes Candice Anne, Rangel Drauzio Eduardo Naretto, Alder-Rangel Alene, Sukmawati Dalia, Aidoo Owusu Fordjour, Acheampong Mavis Agyeiwaa
Department of Crop Science, University of Ghana, Accra, Ghana.
School of Biological Science, Universiti Sains Malaysia, George, Pulau Pinang, Malaysia.
Front Fungal Biol. 2025 Aug 25;6:1660692. doi: 10.3389/ffunb.2025.1660692. eCollection 2025.
Chili pepper exports from Ghana are subject to stringent chemical residue regulations in key export destinations. Consequently, microbial biopesticides are urgently needed to complement current nonchemical control options for key pests of chili pepper, particularly the phytosanitary insect, False Codling Moth (FCM). Thus, the search for native entomopathogenic fungi in Ghanaian farms was initiated in 2023. Seven isolates (UGSUHCI, UGJKCS9, UGJKCS10, UGAFMF8, UGAFM F12, UGNAKC1 and UGKAP1), obtained from agricultural soils in Ghana, showed high virulence against the soil-dwelling stages of FCM under laboratory conditions. To facilitate the selection of these virulent isolates for development into a mycoinsecticide for FCM, the UV sensitivity and virulence following UV exposure were investigated for all seven isolates in this study. All isolates exhibited extreme susceptibility to UV radiation in comparison to similar research. Exposure to simulated full-spectrum solar radiation at 0.6 W/m for 30 min reduced relative conidial germination by 28-40% 48 h following exposure, while 60 min exposure killed all isolates. High insect mortalities were recorded for four isolates, regardless of UV radiation. The findings suggest that an effective UV-protectant formulation could be required for success in the field against fruit and foliar pests of chili pepper, including those of FCM.
加纳的辣椒出口在主要出口目的地面临严格的化学残留规定。因此，迫切需要微生物生物农药来补充目前针对辣椒主要害虫，特别是植物检疫性害虫——无花果小卷蛾（FCM）的非化学防治方法。于是，2023年开始在加纳农场寻找本地昆虫病原真菌。从加纳农业土壤中获得的7个分离株（UGSUHCI、UGJKCS9、UGJKCS10、UGAFMF8、UGAFMF12、UGNAKC1和UGKAP1）在实验室条件下对FCM的土壤栖息阶段表现出高毒力。为便于选择这些高毒力分离株开发成FCM的杀真菌剂，本研究对所有7个分离株的紫外线敏感性和紫外线照射后的毒力进行了研究。与类似研究相比，所有分离株对紫外线辐射都表现出极高的敏感性。暴露于0.6 W/m的模拟全光谱太阳辐射30分钟后，暴露48小时后分生孢子相对萌发率降低28 - 40%，而暴露60分钟则杀死所有分离株。无论紫外线辐射如何，4个分离株都记录到了高昆虫死亡率。研究结果表明，在田间防治辣椒果实和叶部害虫（包括FCM害虫）时，可能需要一种有效的紫外线防护制剂才能取得成功。
