Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA.
Pest Manag Sci. 2020 Aug;76(8):2781-2786. doi: 10.1002/ps.5825. Epub 2020 Apr 7.
Tobacco thrips, Frankliniella fusca (Hinds), is a pest of cotton. Currently, growers rely on neonicotinoid seed treatments to control F. fusca. However, the occurrence of neonicotinoid-resistant F. fusca populations has created new challenges for their management. Development of thrips-active Cry51Aa2.834_16 Bacillus thuringiensis (Bt) toxin expressed in MON 88702 cotton will be an important new tactic for thrips management. Previous studies have shown that MON 88702 causes limited mortality of F. fusca adults and larvae but reduces infestations on seedling cotton by suppressing oviposition from colonizing adults. This suggests that the toxin affects host preference of adult F. fusca. Knowledge of the effect of this trait on F. fusca feeding behavior provides a more complete understanding of MON 88702 activity. Using electropenetrography, we compared the feeding behaviors of adult F. fusca females on MON 88702 cotton and a non-Bt isoline cotton over 2 h. The number of probes, proportion of probes resulting in ingestion, total duration of ingestion, and duration of ingestion per event were measured.
On MON 88702 seedlings, F. fusca probed and ingested fewer times than those on non-Bt cotton. Probes on MON 88702 were less likely to lead to ingestion than on non-Bt cotton. The total duration of ingestion and duration of ingestion per event did not differ between treatments.
The results show that MON 88702 has an antifeedant effect on F. fusca, which provides insight into behavioral responses driving MON 88702 aversion and anti-oviposition documented in previous studies. © 2020 Society of Chemical Industry.
烟粉虱，Frankliniella fusca（Hinds），是棉花的一种害虫。目前，种植者依赖于新烟碱类种子处理剂来控制 F. fusca。然而，新烟碱类抗性 F. fusca 种群的出现给它们的管理带来了新的挑战。在 MON 88702 棉花中表达的对烟粉虱有活性的 Cry51Aa2.834_16 苏云金芽孢杆菌（Bt）毒素的开发将成为烟粉虱管理的一个重要新策略。先前的研究表明，MON 88702 会导致烟粉虱成虫和幼虫的死亡率有限，但通过抑制定植成虫的产卵来减少幼苗棉上的侵染。这表明该毒素会影响烟粉虱成虫的寄主偏好。了解该特性对烟粉虱取食行为的影响，可以更全面地了解 MON 88702 的活性。我们使用电穿透图比较了 2 小时内烟粉虱雌性成虫在 MON 88702 棉花和非 Bt 对照品系棉花上的取食行为。测量了探针的数量、导致摄入的探针比例、摄入的总持续时间以及每次摄入的持续时间。
在 MON 88702 棉苗上，烟粉虱的探针和摄入次数均少于非 Bt 棉苗。在 MON 88702 上的探针导致摄入的可能性小于非 Bt 棉苗。两种处理的摄入总持续时间和每次摄入的持续时间没有差异。
结果表明，MON 88702 对烟粉虱具有抗食作用，这为了解先前研究中记录的 MON 88702 厌恶和抗产卵的行为反应提供了线索。© 2020 化学工业协会。
