权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Genetical and molecular biological analyses on seed dormancy of Echinochloa plants

稗草种子休眠的遗传和分子生物学分析

基本信息

批准号：
10660047
负责人：
YAMASUE Yuji
金额：
$ 2.24万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

(1) Cultivated form of E. oryzicola genetically deficient in seed dormancy was reciprocally hybridized with its weedy form with deep seed dormancy. Frequency distribution of FィイD22ィエD2 hybrids with different dormancy levels in their seeds suggested two major genes for control of the seed dormancy. Seeds derived from inbreeding of all of the FィイD22ィエD2 hybrids that appeared to be recessive homozygotes for the two genes were nondormant.(2) Two mRNA that specifically expressed in dormant seeds were found at an early stage of imbibition when mRNA were compared between dormant and nondormant seeds of both tetraploid and hexaploid Echinochloa plants by differential display. Complimentary DNA of the one (EcD400) had no homology with known proteins, but that of the other (EcD700) was suggested to be mitochondrial HィイD1+ィエD1-ATPase by a database homology assessment. With results of our previous studies, this finding may indicate that seed dormancy of this genus is maintained by aerobic respiration, and the dormancy is released by increasing activity of anaerobic respiration.(3) Both the above hybridization experiment and molecular biological analyses suggested that two genes were involved in the mechanism of seed dormancy. But further studies are required to clarify dormancy levels of the advanced progenies of the hybrids and roles of the respiratory enzyme and EcD400 in a seed of Echinochloa plants.

(1)种子休眠性遗传缺陷的栽培类型与种子深度休眠的杂草类型进行正反交。不同休眠程度的F-ィイ-D22-ィエ-D2杂交种在种子中的频率分布揭示了控制种子休眠的两个主效基因。所有FィイD22ィエD2杂交种的种子均为隐性纯合子，表现为隐性纯合子。(2)用差异显示技术比较四倍体和六倍体藜属植物的休眠种子和非休眠种子，发现有两个在休眠种子吸胀早期特异表达的基因。其中一个(ECD400)与已知蛋白质没有同源性，而另一个(ECD700)经数据库同源性分析，推测为线粒体HィイD1+ィエD1-ATPase。结合我们以往的研究结果，这一发现可能表明该属的种子休眠是通过有氧呼吸维持的，而休眠的解除是通过增加无氧呼吸的活性来实现的。(3)上述杂交实验和分子生物学分析都表明，两个基因参与了种子休眠的机制。但还需要进一步的研究来澄清杂交种高级后代的休眠水平，以及呼吸酶和Echochloa植物种子中ECD400的作用。