丛枝菌根网络介导番茄和分蘖洋葱间钾元素传递的诱因及其作用机理

合理的多样性种植模式能通过增加根际有益微生物改善作物矿质营养、提高作物产量。前期我们发现丛枝菌根网络在分蘖洋葱伴生番茄促生中起作用，并介导了植株间非对称性钾元素传递，但机理不明。本项目拟在已有基础上，(1)利用分子手段和单孢培养等技术，明确分蘖洋葱伴生番茄根际细菌和丛枝菌根真菌(AMF)菌群差异，分离鉴定出伴生番茄根际的差异AMF和解钾菌(KSB)菌株，阐明AMF对KSB的运输作用及其对番茄和分蘖洋葱间钾元素传递的影响；(2)通过遮阴、去叶和调整播期的手段改变植株碳库强度，明确碳库强度变化在丛枝菌根网络介导植株间钾元素传递中的调控作用；(3)通过土壤资源斑块性试验，探明伴生分蘖洋葱引起的土壤养分变化与丛枝菌根网络介导植株间钾元素传递的关系。通过以上研究揭示丛枝菌根网络介导番茄和分蘖洋葱间钾元素传递的诱因及其作用机理，进一步丰富间套作(伴生)促生和高效利用矿质养分的种间互惠机理。

Increasing plant diversity can improve crop mineral nutrients and increase crop yield through increasing rhizosphere beneficial microorganisms. Previously, we found that arbuscular mycorrhizal network played an important role in the promoting effects of potato onion on tomato plant growth mediated by the asymmetric transfer of potassium. However, the underlying mechanisms are not clear. This study will further (1) clarify the differences in rhizosphere bacteria and arbuscular mycorrhizal fungi (AMF) community between tomato and potato onion in intercropping system with molecular methods and single spore culture techniques, and isolate the AMF and potassium solubilizing bacteria (KSB) species of intercropped tomato rhizosphere to elucidate the transport of KSB by AMF and its effects on potassium transfer between the two plants; (2) elucidate the role of plant carbon source strength on the potassium transfer between the two plants mediated by arbuscular mycorrhizal networks by shading, defoliation and adjusting sowing date; (3) reveal the relationship between changes in soil nutrient content of tomato induced by intercropped with potato onion and potassium transfer between the two plants mediated by arbuscular mycorrhizal networks with nutrient patch experiment. This project is expected to reveal the inducing factors and their function mechanisms of potassium transfer between tomato and potato onion mediated by arbuscular mycorrhizal networks. Overall, this study could further enrich the positive interspecific interactions of intercropping (companion cropping) promote plant growth and efficient utilization of mineral nutrients.