Mycorrhizal Cheaters in the Monotropoideae: Costs, Benefits, and Life History Traits of an Unholy Alliance.

brunsepi寄生植物不进行光合作用，它们通过与两种植物相连的菌根真菌间接从绿色植物中获取糖。这种行为使它们成为陆地生态系统中最普遍的互惠关系之一的骗子。我们的目标是了解外寄生植物对其直接和间接寄主的成本和收益，并研究与外寄生幼苗建立相关的生活史特征。我们通过四个特定的假设来解决这些目标，这些假设与共生连续体中的条件变化、对宿主-真菌竞争相互作用的影响以及宿主特异性的生态机制有关。这些假设是通过耦合共生发芽实验在田间与操纵生长室实验。我们在这两种情况下使用真菌和植物的精确分子鉴定。研究结果将提供对菌根共生中植物-寄生端相互作用本质的深入理解，将产生关于这些植物特异性、萌发和发育的新数据，并将进一步开发一个独特的共生欺骗实验系统。这些信息将增加我们对菌根共生的认识，并将有助于我们管理一些稀有和濒危的单足纲物种的种群。

DEB-0108424 BrunsEpiparasitic plants are not photosynthetic, and they indirectly obtain sugars from green plants through a mycorrhizal fungus that is connected to both plants. This behavior makes them cheaters of one of the most widespread mutualisms in terrestrial ecosystems. Our goals are to understand the costs and benefits of epiparasitic plants to their direct fungal and indirect plant hosts, and to examine life history traits related to the establishment of epiparasite seedlings. We address these goals through four specific hypotheses related to conditional changes in the symbiotic continuum, to effects on host-fungal competitive interactions, and to ecological mechanisms for host specificity. These hypotheses are tested by coupling symbiotic germination experiments in the field with manipulative growth chamber experiments. We use precise molecular identification of fungi and plants in both settings. Results will provide an in-depth understanding of the nature of the interactions at the plant-parasitic end the mycorrhizal symbiosis, will yield novel data on specificity, germination, and development of these plants, and will further develop a unique experimental system of symbiotic cheating. This information will increase of our knowledge of mycorrhizal symbiosis, and will help us to manage populations of some of the rare and endangered species in the Monotropoideae.