The crucial role of gibberellic acid on germination of drought-resistant upland rice
The crucial role of gibberellic acid on germination of drought-resistant upland rice
复制标题
赤霉酸对抗旱旱稻发芽的关键作用
DOI：
10.32615/bp.2019.049
复制
发表时间：
2019-01-01
影响因子：
1.5
通讯作者：
Zhao, Q. -Z.
中科院分区：
文献类型：
--
作者：
Li, J. -Z.;Li, M. -Q.;Zhao, Q. -Z.
干旱是限制种子萌发的主要因素之一。为揭示干旱胁迫下高地种子萌发力提高的生理和分子机制，以高地品种IRAT 109和低地水稻品种粤福为材料，研究了干旱胁迫下旱稻种子萌发特性及赤霉素（GA 3）、α-淀粉酶和膨胀素相关基因的表达。PEG胁迫下，高地和低地稻种子发芽率均下降，高地受影响程度小于低地稻。PEG胁迫下，高地的发芽势、根长和芽长均显著高于低地稻。高地发芽种子中GA 3/脱落酸比值、α-淀粉酶活性和可溶性糖含量较高。RNA测序分析表明，14个与赤霉素、α-淀粉酶和扩展蛋白相关的基因在高地中的表达量显著高于低地稻。另一方面，GA 3处理显著提高了高地的发芽势、芽长、根长、α-淀粉酶活性和可溶性糖含量。还诱导了高地α-淀粉酶和扩展蛋白相关基因的高表达。结果表明，GA 3通过提高α-淀粉酶和膨胀素基因的表达，促进干旱胁迫下高地种子萌发。
Drought is one of the main factors restricting seed germination. In order to reveal the physiological and molecular mechanisms of improved germination ability in upland rice under drought stress, we investigated the seed germination characteristics and the expression of genes related to gibberellic acid (GA3), alpha-amylase, and expansin of upland rice cultivar IRAT109 and lowland rice cultivar Yuefu under drought stress induced by 15 % (m/v) polyethylene glycol (PEG) and GA3 application. Seed germination decreased in upland rice and lowland rice under PEG-induced stress; upland rice was less affected than lowland rice. The germination vigour, root length, and shoot length were significantly higher in upland rice than in lowland rice under PEG stress. The GA3/abscisic acid ratio, alpha-amylase activity, and soluble sugar content in the germinated seeds were higher in upland rice. An RNA sequencing analysis revealed that 14 genes related to gibberellins, alpha-amylase, and expansin had a significantly higher expression in upland rice than in lowland rice. On the other hand, application of GA3 significantly increased the germination vigour, shoot length, root length, alpha-amylase activity, and soluble sugar content in upland rice. It also induced higher expressions of alpha-amylase and expansin related genes in upland rice. The results indicate that GA3 plays an important role in promoting seed germination in upland rice under drought stress by increasing the expressions of alpha-amylase and expansin genes.