摘要:铁是高等植物生长发育的必需元素之一,水稻是一种世界性粮食作物。水稻受缺铁胁迫会出现缺绿,长势不佳的症状。γ-氨基丁酸是一种植物生长调节剂,本实验以水稻幼苗为材料,研究了外源添加γ-氨基丁酸对于水稻缺铁反应的调控。缺铁条件下,添加了外源GABA的水稻幼苗相比较未添加外源GABA的水稻幼苗株高降低,新叶长度变短,干鲜重降低,叶绿素含量以及磷、锰、镁、铁等元素的含量也降低,钠、钾、锌元素含量升高,这些结果表明外源添加γ-氨基丁酸降低了水稻地上部的铁含量,加重了水稻缺铁的症状。然而基因表达结果表明,GABA可提高根系中OsIRT1、OsYSL15的表达量,提高根系对于外界铁元素的吸收能力,故猜测外源添加GABA可能是阻止了水稻中铁元素从根往地上部的运输,但作用机理尚需做进一步探究。34929 毕业论文关键词:水稻;缺铁;γ-氨基丁酸
Regulation of GABA to Iron-deficiency in Rice Seedlings
Abstract:Iron is one of the essential elements for the growth and development in higher plants. As a worldwide food crop, rice will exhibit chlorosis and their growth will be inhibited in the iron deficiency condition. γ-aminobutyric acid (GABA) is a kind of plant growth regulator. In this study, rice seedlings were used to study the effect of GABA on the response to iron deficiency. Under the iron deficiency, compared to rice seedlings without GABA, those with GABA have deeper plant height, shorter new leaf, lighter fresh weight and dry weight, less chlorophyll concentration, less the content of P, Mg, Mn and Fe, more the content of Na, K and Zn, which indicates that the addition of exogenous γ-aminobutyric acid reduces the content of Fe in rice seedlings aboveground and aggravate the iron-deficiency symptom. Furthermore, we found that by analyzing the expression of related genes were tested to find whether γ-aminobutyric acid regulate iron deficiency in rice. The results exhibit that GABA can improve the absorption rate of iron by increase the expression of OsNAS1 and OsNAS2 in root. So, we supposed that GABA may prevent the transport of Fe from roots to overground part. But the mechanism needs to be furture studied.
Key words: Rice;Iron-deficiency;GABA
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