PRF/J: The Role of Limiting Resources in Controlling Mutualistic and Parasitic Effects of Mycorrhizae

9403308约翰逊 这项研究将确定哪些因素调节菌根的有效性与其宿主植物的互惠或寄生关系。 要测试的假设是，丰富的有限的土壤资源导致菌根植物分配较少的碳根分泌物，给一个选择性的优势，以寄生形式的泡状丛枝菌根（VAM）真菌。 将在两个NSF长期生态研究（LTER）地点（明尼苏达州的雪松溪自然历史区和新墨西哥州的塞维利亚）的24个施肥、灌溉和对照地块上进行实地调查。 VAM真菌在农业系统中研究相对较好，但在自然生态群落和生态系统中知之甚少，尽管它们在土壤中无处不在。 然而，即使在管理的农业环境中，与我们对农业生态系统其他组成部分的了解相比，这些真菌在很大程度上仍被视为“黑匣子”。 一个更彻底的了解VAM生物学和生态学可能会导致改进的做法，牧场主和农民方面成功的菌根接种计划，而更全面的欣赏自然菌根生物多样性无疑会导致尚未预见的改善管理农业和林业系统。 ***

9403308 Johnson This research will ascertain what factors regulate mycorrhizal effectivity in relation to mutualistic or parasitic relationships with their host plants. To be tested is the hypothesis that enrichment of a limiting soil resource causes mycorrhizal plants to allocate less carbon to root exudates, giving a selective advantage to parasitic forms of vesicular - arbuscular mycorrhizal (VAM) fungi. Fieldwork will be conducted on 24 fertilized, irrigated, and control plots at two NSF Long Term Ecological Research (LTER) sites (Minnesota's Cedar Creek Natural History Area and Sevilleta in New Mexico). %%% VAM fungi, relatively better studied in agricultural systems, are poorly known in natural ecological communities and ecosystems despite their ubiquitousness in soils. Nevertheless even in managed agricultural settings, these fungi are still largely regarded as "black boxes" in comparison to our knowledge of other components of agroecosystems. A more thorough understanding of VAM biology and ecology is likely to lead to improved practices by ranchers and farmers with regard to successful mycorrhizal inoculation programs, while a more comprehensive appreciation of natural mycorrhizal biodiversity will undoubtedly lead to as yet unforeseen improvements in managed agricultural and forest systems. ***