Department of Entomology and Nematology, University of California Davis, Davis, California, United States of America.
University of California Cooperative Extension, Salinas, California, United States of America.
PLoS One. 2019 Apr 18;14(4):e0215446. doi: 10.1371/journal.pone.0215446. eCollection 2019.
Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae) is an invasive stink bug species that feeds on cruciferous plants and can cause substantial damage to crops. Little is known about the dispersal behavior of B. hilaris, but movement is important because of the way this pest moves from senescing weed hosts into crop fields. Perhaps, B. hilaris residing on declining weed hosts become starved, which alters their normal locomotor activity and initiates dispersal. We examined the influence of starvation on the locomotor behavior of multiple life stages of B. hilaris under laboratory and outdoor conditions. We starved nymph (2nd/3rd and 4th/5th instars) and adult (female and male) stages for 0, 24, and 48 h. We measured distance moved in the laboratory and then distance moved and turning ratio outdoors. In the laboratory, the younger nymphs moved shortest distances when starved for 24 h, whereas late-instar nymphs (4th-5th instars) and adult B. hilaris that were starved moved farther than non-starved individuals. In the outdoor setting, environmental conditions, specifically surface temperature were important in determining how starvation affected distance moved. Starved insects were more responsive (moved farther) for a given change in temperature than non-starved insects. At lower temperatures, B. hilaris tended to move farther when non-starved and at higher temperatures, moved longer distances when starved, at least for certain stages. Increased starvation also led to more directional movement. Our results indicate that starvation influences aspects of movement for B. hilaris and that these effects can be influenced by temperature.
Bagrada hilaris (Burmeister)（半翅目：Pentatomidae）是一种入侵性臭虫物种，以十字花科植物为食，会对作物造成严重损害。目前对 B. hilaris 的扩散行为知之甚少，但由于这种害虫从衰老的杂草宿主转移到作物田的方式，移动很重要。也许，栖息在衰落杂草宿主上的 B. hilaris 会挨饿，这会改变它们的正常运动活动并引发扩散。我们在实验室和户外条件下研究了饥饿对 B. hilaris 多个生命阶段的运动行为的影响。我们将若虫（2 龄/3 龄和 4 龄/5 龄）和成虫（雌性和雄性）饥饿 0、24 和 48 小时。我们在实验室测量了移动的距离，然后在户外测量了移动的距离和转弯比。在实验室中，饥饿 24 小时的年轻若虫移动的距离最短，而晚龄若虫（4-5 龄）和饥饿的成年 B. hilaris 移动的距离比未饥饿的个体远。在户外环境中，环境条件，特别是表面温度，对确定饥饿如何影响移动距离非常重要。与未饥饿的昆虫相比，饥饿的昆虫对温度变化的反应更灵敏（移动得更远）。在较低的温度下，B. hilaris 在未饥饿时往往会移动得更远，而在较高的温度下，饥饿时会移动得更远，至少在某些阶段是这样。饥饿程度的增加也导致了更具方向性的运动。我们的结果表明，饥饿会影响 B. hilaris 的运动行为的某些方面，并且这些影响可以受到温度的影响。
