Mechanisms of Plant-Herbivore Interactions

私家侦探的意图是探索相互作用的机制 在陆生植物和它们的食草动物中， 直接相互作用（如食草动物食用植物）， 间接相互作用（例如，食草动物可能会影响 植物竞争通过增加土壤养分浓度）。 前人对老田禾本科和草本植物的研究及其主要成果 食草动物蚱蜢在中环的研究地点 明尼苏达州表明，（1）植物受到限制， 土壤氮，（2）蝗虫减少植物丰度和影响 植物种类组成，（3）蝗虫是有限的， 争夺植物的食物 根据这些研究， 研究人员提出了三个实验来展示这些 互动链接： (1)花园实验中，不同的影响， 植物对土壤氮，植物对其他植物，蝗虫对 植物，蝗虫对氮，蝗虫对其他 蝗虫将单独和合并计量， 土壤养分、植物物种组成和 蝗虫密度将得到控制， (2)在田间试验中， 物种将被操纵来看待这些相同的潜力 对自然界的影响，以及 (3)在实验室饲养实验中， 将被喂食不同的植物种类和它们的偏好， 测量生理反应。 这些实验将测量 直接和间接的植物-食草动物相互作用 控制条件，决定草食动物饮食的作用 选择在这些相互作用，并确定的重要性， 这些在含有同一种植物的真实的群落中的相互作用 和蚱蜢物种。 这项研究可能是第一个解决 这三个目标都在一个相对简单的系统中。 的 结果将为预测结果提供基础， 这些相互作用，因此，植物的结构， 草食动物群落 //

The P.I.'s intend to explore the mechanisms of interaction among terrestrial plants and their herbivores, including both direct interactions (e.g. herbivores consume plants) and indirect interactions (e.g. herbivores may affect the outcome of plant competition by increasing soil nutrient concentration). previous studies of old field grasses and herbs and their major herbivores, grasshoppers, at their study site in central Minnesota indicate that (1) plants are limited by and compete for soil nitrogen, (2) grasshopper reduce plant abundance and affect plant species composition, and (3) grasshoppers are limited by and compete for plant food. Based on these studies, the investigators propose three experiments to show how these interactions link together: (1) garden experiments in which the effects of different plants on soil nitrogen, plants on other plants, grasshoppers on plants, grasshoppers on nitrogen, and grasshoppers on other grasshoppers will be measured separately and in combination on plots where soil nutrients, plant species composition, and grasshopper densities will be controlled, (2) field experiments in which densities of six grasshopper species will be manipulated to look at these same potential effects in a natural community, and (3) laboratory feeding experiments in which grasshoppers will be fed different plant species and their preference and physiological responses measured. These experiments will measure the mechanisms and strength of direct and indirect plant - herbivore interactions under controlled conditions, determine the role of herbivore diet selection in these interactions, and determine the importance of these interactions in a real community containing the same plant and grasshopper species. This study may be the first to address all three goals in a single, relatively simple, system. The results will provide a foundation for predicting the outcome of these interactions and consequently, the structure of plant and herbivore communities. //