外源激素ABA影响新疆荒漠盐生植物异子蓬异型种子萌发机制初探

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 外源激素ABA影响新疆荒漠盐生植物异子蓬异型种子萌发机制 DOI: 10.5846/stxb201405130978 作者: 作者单位: 新疆大学生命科学与技术学院/新疆生物资源基因工程重点实验室,新疆大学生命科学与技术学院/新疆生物资源基因工程重点实验室,新疆大学生命科学与技术学院/新疆生物资源基因工程重点实验室,新疆大学生命科学与技术学院/新疆生物资源基因工程重点实验室,新疆大学生命科学与技术学院/新疆生物资源基因工程重点实验室,新疆大学生命科学与技术学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(31260037,31060027);新疆自治区优秀青年科技人才培养项目(2013721013);新疆生物资源基因工程重点实验室开放基金(XJDX0201-2011-03) Effects of exogenous abscisic acid on heteromorphic seed germination of Suaeda aralocaspica, a typical halophyte of Xinjiang desert region Author: Affiliation: Xinjiang Key Laboratory of Biological Resources and Genetic Engineering,College of Life Science and Technology,Xinjiang University,Xinjiang Key Laboratory of Biological Resources and Genetic Engineering,College of Life Science and Technology,Xinjiang University,Xinjiang Key Laboratory of Biological Resources and Genetic Engineering,College of Life Science and Technology,Xinjiang University,Xinjiang Key Laboratory of Biological Resources and Genetic Engineering,College of Life Science and Technology,Xinjiang University,Xinjiang Key Laboratory of Biological Resources and Genetic Engineering,College of Life Science and Technology,Xinjiang University,Xinjiang Key Laboratory of Biological Resources and Genetic Engineering,College of Life Science and Technology,Xinjiang University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以新疆荒漠盐生植物异子蓬(Suaeda aralocaspica)异型种子为材料,通过外源ABA直播(长时间)与浸种(短时间)处理分别研究不同浓度(0、0.5、1.0、5.0、10.0 μmol/L)ABA对异型种子萌发、幼苗生长的影响,并通过定量PCR技术分析与萌发相关的ABC转运蛋白基因、丝裂原活化蛋白激酶激酶基因和DNA修复和转录因子基因在5.0 μmol/L ABA处理下的表达规律,探讨外源ABA影响异子蓬异型种子萌发差异的机制。结果显示:(1)外源ABA直播处理下,褐色种子萌发及幼苗生长均受到明显抑制,黑色种子的萌发和幼苗生长在低浓度被促进,较高浓度被显著抑制;短时间浸种处理,能够同时促进异型种子的萌发及幼苗生长,且随ABA浓度增加促进效应增强。(2)直播萌发后,褐色种子中3个基因的表达量与对照相比均不变或降低表达(除了DNA修复和转录因子基因在8 h显著升高),黑色种子与对照相比均上调表达(除了ABC转运蛋白基因在8h显著下调);短时间浸种萌发后,褐色种子中3个基因的表达量均比对照显著升高,黑色种子中升高不明显。基因表达规律与种子萌发结果趋势一致,暗示ABA浸种可能触发了异子蓬种子萌发内在机制并对随后的萌发过程产生促进作用。而黑色种子对ABA处理表现出较好的萌发响应,可能是其幼苗能抵御荒漠地区逆境环境的重要原因。 Abstract:In order to examine the effects of exogenous abscisic acid (ABA) on germination and seedling growth of heteromorphic Suaeda aralocaspica seeds, we either directly sowed (long-term treatment) or presoaked (short-term treatment) the two seed morphs under different concentrations (0, 0.5, 1.0, 5.0, 10.0 μmol/L) of ABA. To further understand the molecular mechanism of exogenous ABA effects on different germination characteristics of heteromorphic seeds of S. aralocaspica, we examined the expression of three genes with known functions in seed germination:ABC transporter family protein, mitogen-activated protein kinase kinase, and DNA repair and transcription factor. Gene expression was analyzed using quantitative PCR on directly sown and presoaked seeds treated with 5.0 μmol/L ABA. The results revealed two findings:(1) For directly sown seeds, different concentrations of exogenous ABA inhibited germination and seedling growth of brown seeds significantly, while these processes in black seeds were accelerated by lower concentrations of ABA, rather than by higher concentrations. In contrast, pre-soaking promoted germination and seedling growth of both types of seed, and this effect increased at higher concentrations of ABA. (2) Quantitative PCR revealed that, for directly sown brown seeds, only the expression level of the gene for DNA repair and transcription factor increased significantly at 8 h compared to that of control seeds. In black seeds, the genes for DNA repair and transcription factor and for mitogen-activated protein kinase kinase were significantly up regulated compared to those in the control. For pre-soaked seeds, treatment with ABA markedly increased the expression levels of all three genes in brown seeds rather than in black seeds. Expression patterns of the three genes were consistent with the results of seed germination. These results suggest that presoaking with ABA may trigger the internal germination mechanism of S. aralocaspica seeds and accelerate the subsequent germination process. The stronger response of black seeds to ABA treatment may be an important adaptation to the harsh and unpredictable environment of Xinjiang desert region. 参考文献 相似文献 引证文献