Facilitation of ground-dwelling spider predation on mirid bugs by horizontal webs built by Tetragnatha spiders in organic paddy fields

红纹窄盲蝽是水稻生产中的主要害虫，常滞留在水稻上层以稻穗为食。然而，盲蝽经常被肖肖龙属的水平网捕获。蜘蛛和下降到稻田的底层，在那里他们被捕食的地面上居住的掠食者。据推测，肖峭属（Tetragnathaspp.）蜘蛛通过特征介导效应（trait-mediatedeffects）促进狼蛛捕食昆虫，其中它们的水平网迫使昆虫落在地面上或接近地面，从而进入狼蛛的狩猎区。结合现场测量的蜘蛛的分子肠道内容物分析显示，测试呈阳性的盲蝽捕食狼蛛的数量显着增加的密度肖龙属。稻田里的蜘蛛我们还观察到了正相关的肖峭属。丰富度和总覆盖由他们的网在稻田。这些结果部分支持了我们的假设。

The mirid bug Stenotus rubrovittatus, a major insect pest in rice production, usually remains in the upper layer of paddies to feed on rice ears. However, the mirids are frequently trapped by horizontal webs of Tetragnatha spp. spiders and fall to the bottom layers of paddies where they are preyed upon by ground-dwelling predators. It is hypothesized that Tetragnatha spp. spiders facilitate bug predation by wolf spiders through trait-mediated effects, in which their horizontal webs force the bugs onto or near the ground and thereby into the hunting zones of wolf spiders. Molecular gut-content analysis of spiders coupled with field measurements revealed that the number of wolf spiders that tested positive for mirid bug predation increased significantly with the density of Tetragnatha spp. spiders in the paddies. We also observed a positive relationship between Tetragnatha spp. abundance and total cover by their webs in paddies. These results partially support our hypothesis.