Ambele Chaba F, Ekesi Sunday, Bisseleua Hervé D B, Babalola Olubukola O, Khamis Fathiya M, Djuideu Christian T L, Akutse Komivi S
International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772-00100 Nairobi, Kenya.
Food Security and Safety, Faculty of Agriculture, Science and Technology, North-West University, South Africa, Private Bag X2046, Mmabatho 2745, South Africa.
J Fungi (Basel). 2020 Aug 5;6(3):126. doi: 10.3390/jof6030126.
This study was conducted in the scope of developing a sustainable effective approach against subterranean termite pests using entomopathogenic and endophytic fungus-based biopesticides. Termites, spp. workers, were tested for their susceptibility to 15 entomopathogenic fungal isolates through the direct spraying of conidia suspensions at 1 × 10 conidia/mL. In general, all the isolates screened were pathogenic, with 100% mortality 4-7 days post-inoculation. However, the most virulent isolates were Cb15-III; the isolates ICIPE 30 and ICIPE 60; F3ST1; and the isolates ICIPE 279, ICIPE 706 and ICIPE 662. These isolates were further tested for their endophytic colonization of cocoa seedlings using seed soaking, soil drench and foliar spray at 1 × 10 conidia/mL. The colonization of the plant tissues by the fungi was determined using a culture-based technique. Only the isolates ICIPE 706 and ICIPE 279, and F3ST1 colonized the cocoa seedlings, with varied colonization rates among isolates and inoculation methods. Three naturally occurring endophytes-, and -were also isolated from the cocoa seedling tissues. These findings suggest that cocoa seedlings are conducive to endophytic fungal growth either occurring naturally or from artificial inoculation Our findings could possibly lead to an innovative approach to the management of herbivory and subterranean termite pests in cocoa agroforests.
本研究是在开发一种可持续有效的防治地下白蚁害虫方法的范围内进行的，该方法使用基于昆虫病原真菌和内生真菌的生物农药。对白蚁属的工蚁进行了测试，通过以1×10个分生孢子/毫升的浓度直接喷洒分生孢子悬浮液，检测它们对15种昆虫病原真菌分离株的敏感性。总体而言，所有筛选出的分离株都具有致病性，接种后4 - 7天死亡率达100%。然而，毒性最强的分离株是Cb15 - III；分离株ICIPE 30和ICIPE 60；F3ST1；以及分离株ICIPE 279、ICIPE 706和ICIPE 662。使用种子浸泡、土壤浇灌和叶面喷施，以1×10个分生孢子/毫升的浓度对这些分离株在可可幼苗上的内生定殖情况进行了进一步测试。采用基于培养的技术确定真菌在植物组织中的定殖情况。只有分离株ICIPE 706和ICIPE 279以及F3ST1定殖于可可幼苗，不同分离株和接种方法的定殖率各不相同。还从可可幼苗组织中分离出三种天然存在的内生真菌。这些发现表明，可可幼苗有利于内生真菌的自然生长或人工接种生长。我们的研究结果可能会为可可农林中食草动物和地下白蚁害虫的管理带来创新方法。
