Department of Entomology, The University of Arkansas, Lonoke Agricultural Center, Lonoke, AR.
Department of Entomology, Texas A&M University, College Station, TX.
J Econ Entomol. 2019 May 22;112(3):1098-1104. doi: 10.1093/jee/toz012.
Horizontal transmission of Helicoverpa armigera nucleopolyhedrovirus (HearNPV) has been found to occur through several pathways involving abiotic factors such as soil, wind, and rain, and biotic factors such as predators, parasitoids, and infected hosts. Previous studies examining horizontal transmission through certain biological carriers speculated they were likely not significant in increasing infection rates, however; these studies only focused on a relatively small number of arthropods present within a field setting. This study was conducted to evaluate the horizontal transmission potential of HearNPV by all potential biological carriers when applied as a foliar bioinsecticide or as virus-infected, nonmotile Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) larvae in a soybean field. Soybean plots were either sprayed with HearNPV or infested with late-stage HearNPV-infected larvae, and sample zones were sampled 3, 7, 10, 14, 17, and 21 days after the infestation, and analyzed for viral presence using PCR. We then identified HearNPV carriers through contamination from the application (involuntary) or through contact with a HearNPV-infected larva (voluntary). Both were confirmed through PCR analysis. Regardless of application technique, on average, HearNPV was capable of disseminating up to 61.0 m in 3 d after inoculation and was found within the sampled canopy 13-21 d after inoculation. Several arthropods were identified as novel carriers of HearNPV. Results from this study indicate that many novel HearNPV carriers are likely important in disseminating HearNPV.
棉铃虫核多角体病毒（HearNPV）的水平传播已被发现通过多种途径发生，涉及非生物因素如土壤、风和雨，以及生物因素如捕食者、寄生蜂和感染宿主。以前研究通过某些生物载体研究水平传播时推测它们不太可能显著增加感染率，然而；这些研究仅集中于田间环境中存在的相对较少的节肢动物。本研究旨在评估 HearNPV 通过所有潜在生物载体的水平传播潜力，这些载体作为叶面生防剂或作为携带 HearNPV 的非运动性棉铃虫（Helicoverpa zea（Boddie））（鳞翅目：夜蛾科）幼虫在大豆田中使用时的情况。大豆田要么喷洒 HearNPV，要么感染晚期 HearNPV 感染的幼虫，然后在感染后 3、7、10、14、17 和 21 天进行采样区采样，并通过 PCR 分析病毒的存在。然后，我们通过应用（非自愿）或与感染 HearNPV 的幼虫接触（自愿）来识别 HearNPV 载体。两者都通过 PCR 分析得到证实。无论应用技术如何，平均而言，HearNPV 在接种后 3 天内能够传播高达 61.0 m，并且在接种后 13-21 天内在采样冠层内发现。几种节肢动物被确定为 HearNPV 的新载体。本研究结果表明，许多新的 HearNPV 载体可能在传播 HearNPV 方面非常重要。
