Bacillus thuringiensis impacts on primary and secondary baculovirus transmission dynamics in Lepidoptera.
Bacillus thuringiensis impacts on primary and secondary baculovirus transmission dynamics in Lepidoptera.
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DOI：
10.1016/j.jip.2015.09.008
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发表时间：
2015-11
影响因子：
3.4
通讯作者：
H. Hesketh;R. Hails
中科院分区：
文献类型：
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作者：
H. Hesketh;R. Hails
昆虫病原微生物之间的协同相互作用有可能被用来改善无脊椎害虫的生物防治，但缺乏描述多病原体传播动力学的种群水平的经验数据。我们研究了苏云金芽孢杆菌库斯塔基亚种（Btk）和杆状病毒Panolis火核多角体病毒（PaflNPV）在鳞翅目Mamestra芸苔幼虫实验田群体中的共同接种对病毒传播动态的影响。我们确定了 Btkin 的存在如何影响原发性和继发性 PaflNPV 传播。当 Btk 与 PaflNPV 共同接种时，与单独接种病毒的试验相比，初次传播研究中的病毒死亡率比例增加。 Btk 和 PaflNPV 施用之间最多延迟 4 天不会影响原发性病毒死亡率，表明接种之间的延迟不太可能影响两种病原体的生物防治潜力。存在 Btk 的地块中尸体的病毒产量显着低于仅存在病毒的地块，并且引入的二次传播幼虫的二次循环显着减少。杆状病毒传播（按照不同处理中未感染幼虫的比例）通过“避难”模型进行描述，该模型允许易感性和病原体暴露的异质性。我们讨论了宿主进食率、病毒的空间分布以及昆虫宿主内病原体之间的相互作用等因素如何可能影响传播。这项研究提高了对宿主种群内病原体影响以及如何利用病原体混合物进行害虫生物防治的了解。
Synergistic interactions between entomopathogenic micro-organisms can potentially be exploited to improve biological control of invertebrate pests but empirical data at the population level describing multiple-pathogen transmission dynamics is lacking. We examined how co-inoculation ofBacillus thuringiensissubsp.kurstaki(Btk) and the baculovirusPanolis flammeanucleopolyhedrovirus (PaflNPV) in an experimental field population of LepidopteranMamestra brassicaelarvae impacted on viral transmission dynamics. We determined how the presence ofBtkinfluenced primary and secondaryPaflNPV transmission. WhenBtkwas co-inoculated withPaflNPV, there was increased proportional viral mortality in primary transmission studies compared to plots with virus alone. A delay of up to 4 days between applications ofBtkandPaflNPV did not impact on primary viral mortality, indicating that a lag between inoculations was unlikely to affect the biocontrol potential of the two pathogens. Viral yields from cadavers in plots withBtkpresent were significantly lower than those from plots with virus only, and secondary cycling to introduced secondary transmission larvae was significantly reduced. Baculovirus transmission (in terms of the proportion of uninfected larvae in different treatments) was described by a ‘refuge’ model that allowed for heterogeneity in susceptibility and pathogen exposure. We discuss how transmission may be potentially affected by factors such as host feeding rate, spatial distribution of virus and interactions between pathogens within the insect host. This study improves understanding of the impact of pathogens within host populations and how mixtures of pathogens may be exploited for biocontrol of insect pests.