Eisentoxizität bei Nassreis

湿米中铁的毒性

• 批准号: 60740655
• 负责人: Professor Dr. Mathias Becker
• 金额: --
• 依托单位: Bereich Pflanzenernährung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/60740655?language=en
• 关键词: Eisentoxizit; bei; Nassreis

Iron toxicity in lowland rice is a condition caused by the microbial reduction of iron and involves an excessive uptake of Fe (II) by the rice roots and its acropetal translocation into the leaves. There, Fe(ll) can cause oxidative stress via an elevated production of oxygen radicals. The severity of the stress and its damaging effects on rive depend mainly on the amount of Fe (II) and the time of its occurrence and on type and extend of rice cultivar's tolerance mechanisms. We hypothesize that the environment-specific spatio-temporal variation in conditions of iron toxicity occurrence requires differential expression of adaptation mechanisms and their matching with prevailing iron stress situations. The type and the efficiency of adaptation mechanisms will be evaluated in representative hydroponically-grown lowland rice cultivars as follows: (1) Identification of tolerant cultivars: a) symptom expression and tissue Fe content at different growth stages; b) Dynamics of 59Fe-translocation. (2) Evaluation of adaptation strategies: a) Strategy I (Exclusion): Determination of the oxidation power of roots; b) Strategy II (translocation and partitioning): Quantification of Fe and stress signals in xylem and stem tissues; c) Strategy III (tissue tolerance): Avoidance of oxidative stress by the activity of radical-scavenging enzymes. (3) Classification of adaptation strategies regarding their effectiveness to control/tolerate different Fe stress types. The comparative evaluation is seen to allow the assessment and differentiation of adaptation mechanisms required for lowland rice to cope with the diverse conditions of iron toxicity occurrence.

低地水稻的铁毒是由铁的微生物还原引起的，并且涉及水稻根部过量吸收Fe（II）并将其向顶转运到叶片中。在那里，Fe（II）可以通过氧自由基的产生增加而引起氧化应激。胁迫的严重程度及其对水稻的伤害效应主要取决于Fe（II）的量和发生的时间以及水稻品种耐性机制的类型和程度。我们假设，特定环境的时空变化的条件下，铁毒性的发生需要差异表达的适应机制和他们的匹配与流行的铁胁迫的情况。本研究以具有代表性的低地水栽水稻品种为研究对象，通过以下几个方面对水稻适应机制的类型和效率进行了评价：（1）耐性品种的鉴定：（a）不同生育期症状表现和组织铁含量;（B）~（59）Fe转运动态。(2)适应策略的评估：a）策略I（排除）：根的氧化能力的测定; B）策略II（易位和分配）：木质部和茎组织中的Fe和胁迫信号的定量; c）策略III（组织耐受性）：通过自由基清除酶的活性避免氧化胁迫。(3)分类的适应策略，其有效性，以控制/容忍不同的铁胁迫类型。比较评价被认为是允许评估和分化的适应机制所需的低地水稻，以科普不同的条件下，铁毒性的发生。