Integrated pest management of thrips (Thysanoptera-Thripidae) on British Columbia field crops

蓟马是一种以多种农作物为食的小昆虫，会造成经济损失。西部花蓟马（WFT）、西部富兰克林蓟马（Frankliniella occidentalis）等害虫是不列颠哥伦比亚省和加拿大其他地区温室种植蔬菜和花卉的严重害虫。最近，在不列颠哥伦比亚省的各种大田作物上报道了蓟马的问题。日中性草莓不仅在一个果期结出果实，而且在整个生长季节都能结出果实。由于白昼中性草莓品种现在在不列颠哥伦比亚省种植得更广泛，草莓花和果实容易受到蓟马的损害，时间更长，据报道损害更多。草莓WFT的经济阈值可以从北美其他地方获得，但对BC种植者没有优化。此外，还没有研究确定利用捕食性昆虫对BC草莓白腹枯病进行生物防治的可能性。在这个项目中，将进行实验室和温室试验，以制定草莓白腹枯病的危害阈值，并测试生物防治产品对这种害虫的效果。除了在草莓上报道的问题外，最近还观察到在蓟马存在的情况下马铃薯植物严重的枯萎。枯死症状可能是由番茄斑疹枯萎病病毒（TSWV）引起的，该病毒通过番茄斑疹枯萎病传播给植株，但尚未在BC种群中检测到WFT中是否存在TSWV。在这个项目中，将利用DNA分析对田间采集的蓟马和马铃薯叶片进行TSWV检测。本项目完成的研究将使有害生物管理咨询公司的有害生物监测活动更加精确，从而受益。提高WFT管理建议的精确度可以减少杀虫剂的施用。本研究为该害虫的生物防治提供了一种更可持续的防治策略。检测TSWV的工作将有助于解释最近发生的与蓟马有关的马铃薯枯背。

Thrips are small insects that feed on a variety of agricultural crops and cause economic damage. Pest species like the western flower thrips (WFT), Frankliniella occidentalis, are serious pests of greenhouse-grown vegetables and flowers in British Columbia (BC) and elsewhere in Canada. Recently, problems have been reported with thrips on various field-grown crops in BC. Day-neutral strawberries produce fruit, not just during one fruiting period, but throughout the available growing season. Because day-neutral strawberry varieties are now grown more extensively in BC, strawberry flowers and fruits are susceptible to damage by thrips for a longer period and more damage is reported. Economic thresholds for WFT on strawberries are available from elsewhere in North America, but are not optimized for BC growers. In addition, no work has been done to determine the potential for using predatory insects for biological control of WFT on BC strawberries. In this project, laboratory and greenhouse trials will be done to develop a damage threshold for WFT on strawberries and to test the efficacy of biological control products on this pest. In addition to problems reported on strawberry, severe diebacks of potato plants have been recently observed in the presence of thrips. The dieback symptoms may be caused by Tomato Spotted Wilt Virus (TSWV) that is transmitted to plants by WFT, but the presence of TSWV in WFT has not been tested in BC populations. In this project, field-collected thrips and potato foliage will be tested for the presence of TSWV using DNA analysis. The research to be completed in this project will benefit pest management consulting companies by making their pest monitoring activities more precise. Increased precision in WFT management recommendations could result in reductions in the application of insecticide applications. Our work on WFT biological control could provide a more sustainable management strategy for this pest. Work to detect TSWV will aid in development of an explanation for thrips-associated diebacks in potato that have recently occurred.