Agricultural Entomology, Ethiopian Institute of Agricultural Research, Ambo, Oromia, 37, Ethiopia.
Nematology, Ethiopian Institute of Agricultural Research, Ambo, Oromia, 37, Ethiopia.
F1000Res. 2025 Jan 3;12:1601. doi: 10.12688/f1000research.138237.2. eCollection 2023.
Termites are a major insect pest affecting agricultural production and woody materials. They cause severe devastation in the ecosystem, and lead to bare soil. This phenomenon causes the soil to become difficult to plow, which in turn leads to a reduction in the productivity of crops. It can cause 100 % yield losses based on crop types, level of the damage, and size of its populations. To manage this pest, different management options have been evaluated in Ethiopia. While insecticide usage is the dominant option, less attention has been given to Entomopathogenic Nematode (EPN) based management options. Therefore, this research was initiated to screen locally collected EPN isolates and evaluate promising isolates under field conditions on maize crop.
37 EPN isolates were screened under laboratory condition, while two isolates were evaluated at field condition. The screening of EPN isolates was laid out in a completely randomized design, and the field evaluation used a completely randomized block design, and treatments were replicated thrice. Mortality of insect, damaged root, stem, cob, damage severity, foraging termites, and yield of the crop data were collected.
The study indicated that all screened EPN isolates caused mortality on termites under laboratory conditions. The isolates achieved complete mortality of the insect pest within 12 days of exposure. The finding indicated that AEH and S#50 were the more pathogenic and virulent isolates on termites under laboratory conditions and taken to field study. The S#50 isolate was most pathogenic and reduced the infestation and severity of the insect pest on the maize crop under field conditions.
This result showed that the entomopathogenic nematode isolates have the potential to manage subterranean termites in the maize field. Future studies should be based on collection of local isolates and develop a full package for the virulent isolates.
白蚁是影响农业生产和木质材料的主要昆虫害虫。它们在生态系统中造成严重破坏，导致土壤裸露。这种现象导致土壤难以耕种，从而降低了作物的生产力。根据作物类型、损害程度和种群规模，白蚁可导致 100%的产量损失。为了管理这种害虫，在埃塞俄比亚已经评估了不同的管理选择。虽然杀虫剂的使用是主要选择，但对基于昆虫病原线虫（EPN）的管理选择的关注较少。因此，这项研究旨在筛选当地收集的 EPN 分离物，并在玉米作物的田间条件下评估有前途的分离物。
在实验室条件下筛选了 37 个 EPN 分离物，同时在田间条件下评估了两个分离物。EPN 分离物的筛选采用完全随机设计，田间评估采用完全随机区组设计，处理重复三次。收集昆虫死亡率、受损根系、茎、玉米穗、损伤严重程度、觅食白蚁和作物产量数据。
研究表明，所有筛选的 EPN 分离物在实验室条件下均可引起白蚁死亡。分离物在暴露 12 天内可使昆虫害虫完全死亡。研究结果表明，AEH 和 S#50 是在实验室条件下对白蚁更具致病性和毒力的分离物，并被带到田间研究。S#50 分离物在田间条件下对玉米作物上的地下白蚁具有最强的致病性，并减少了其侵染和严重程度。
本研究结果表明，昆虫病原线虫分离物具有在玉米田中管理地下白蚁的潜力。未来的研究应基于收集当地分离物并开发针对毒力分离物的完整方案。
