酸性土壤是世界上主要的问题土壤，而锰毒是酸性土壤上作物生长的主要限制因子。挖掘植物遗传潜力培育耐锰作物新品种是克服锰毒害问题的经济有效途径，而阐明植物锰毒及抗性机制是利用现代生物技术培养新品种的前提。近年来南方酸性土壤上的甘蔗出现严重幼苗缺铁黄化问题，对我国蔗糖产业的威胁巨大。我们前期掌握的研究证据表明，过多的锰是导致酸性土壤上甘蔗幼苗缺铁黄化的主要因素，然而相关的机制尚不清楚。为揭示锰诱导甘蔗缺铁黄化及抗性的机制，本项目拟研究：（1）缺铁诱导甘蔗麦根酸类物质的分泌、难溶性铁吸收及其对甘蔗锰抗性的影响；（2）锰对甘蔗幼苗铁利用的影响以及锰胁迫下抗氧化系统、铁还原、一氧化氮信号、铁蛋白对甘蔗铁动态平衡、铁活性及幼苗黄化的调控；（3）过多的锰对甘蔗幼苗叶绿素合成与分解的影响及甘蔗的抗性。本研究对于抗锰毒甘蔗新品种培育、酸性土壤上甘蔗缺铁黄化问题的解决有重大意义并有助于揭示植物铁锰互作的本质。

Aicd soils are the main problem soils in the world, while excess manganese is the main factor limiting crop development in acid soils. Breeding manganese-resistant crop cultivars by developing plant′s genetic potential is an economic and effective way to solve the problem in acid soils, while the elucidation of the mechanisms for manganese toxicity and resistance in plants is the precondition to breed manganese-resistant crop cultivars. The sugarcane production on acid soils in the south of China have been suffering from serious chlorsis problem, which has threatened country's sugar-industry safe seriously. Although our primary study results have revealed that the chlorsis was mainly resulted from excess manganese in the soils, correspond mechanisms have remain unclear. To elucidate the mechanisms for manganese tocixity and resistance in sugarcane, studies are carried out including: (1) iron-deficiency induced secretion of phytosiderophore and utilization of sparingly soluble iron, and their impacts on excess-manganese resistance in sugarcane seedlings；（2）the effect of excess manganese on plant iron-ultilization, the regulation of both seedlings chloresis, and the activity and homeostasis of iron by aniti-superoxidation system, iron redox, NO signaling and ferritin in sugarcane; (3) excess manganese effects on the synthesis and degradation of chlorophyll, and plant resistance to this effects. These studies have very important consequences for breeding manganese-resistant crop cultivars, solving the problem of sugarcane chlorsis on acid soils, and would be facilitate for making clear the nature of iron-manganese antagonistic effect in plants