Hummadi Esam H, Dearden Alexander, Generalovic Tomas, Clunie Benjamin, Harrott Alexandria, Cetin Yarkin, Demirbek Merve, Khoja Salim, Eastwood Dan, Dudley Ed, Hazir Selcuk, Touray Mustapha, Ulug Derya, Hazal Gulsen Sebnem, Cimen Harun, Butt Tariq
Department of Biotechnology, College of Science, University of Diyala, Diyala, Iraq.
Department of Biosciences, College of Science, Swansea University, SA2 8PP, UK.
Biol Control. 2021 Apr;155:104527. doi: 10.1016/j.biocontrol.2020.104527.
The entomopathogenic fungus (EPF) occupies the same ecological niche as entomopathogenic nematodes (EPN), with both competing for insects as a food source in the rhizosphere. Interactions between these biocontrol agents can be antagonistic or synergistic. To better understand these interactions, this study focussed on investigating the effect of volatile organic compounds (VOCs), 1-octen-3-ol and 3-octanone, on EPN survival and behaviour. These VOCs proved to be highly toxic to the infective juveniles (IJs) of the EPN , and with mortality being dose dependent. Chemotaxis studies of IJs in Pluronic F127 gel revealed significant preference for the VOCs compared with controls for all tested concentrations. The VOCs also impacted on the test insects in a dose-dependent manner with 3-octanone being more toxic to , and larvae than 1-octen-3-ol. Mortality of and larvae was significantly higher when exposed to relatively high doses (>25%) of 3-octanone. Lower doses of 3-octanone and 1-octen-3-ol immobilised test insects, which recovered after exposure to fresh air for 2 hrs. In depth studies on showed that exposure of IJs to > 10% concentration of 3-octanone or 1-octen-3-ol negatively affected infectivity whereas exposure to lower doses (0.1%, 0.01%) had no effect. The VOCs affected IJs, reducing penetration efficacy and the number of generations inside but they failed to inhibit the bacterial symbiont, . The ecological significance of VOCs and how they could influence EPF-EPN insect interactions is discussed.
昆虫病原真菌（EPF）与昆虫病原线虫（EPN）占据相同的生态位，二者在根际环境中都将昆虫作为食物来源进行竞争。这些生物防治剂之间的相互作用可能是拮抗的或协同的。为了更好地理解这些相互作用，本研究着重调查挥发性有机化合物（VOCs）1-辛烯-3-醇和3-辛酮对EPN存活和行为的影响。事实证明，这些VOCs对EPN的感染性幼虫（IJs）具有高毒性，且死亡率呈剂量依赖性。在普朗尼克F127凝胶中对IJs进行的趋化性研究表明，与所有测试浓度的对照相比，IJs对VOCs具有明显的偏好。VOCs也以剂量依赖的方式影响受试昆虫，3-辛酮对[具体昆虫名称]幼虫的毒性比1-辛烯-3-醇更大。当暴露于相对高剂量（>25%）的3-辛酮时，[具体昆虫名称]幼虫的死亡率显著更高。较低剂量的3-辛酮和1-辛烯-3-醇会使受试昆虫麻痹，在暴露于新鲜空气2小时后恢复。对[具体昆虫名称]的深入研究表明，将IJs暴露于>10%浓度的3-辛酮或1-辛烯-3-醇会对其感染力产生负面影响，而暴露于较低剂量（0.1%，0.01%）则没有影响。VOCs影响IJs，降低其穿透效力和在[具体昆虫名称]体内的繁殖代数，但它们未能抑制共生细菌[细菌名称]。本文讨论了VOCs的生态意义以及它们如何影响EPF-EPN与昆虫的相互作用。
