【作者】 周浩；

【导师】 彭克勤； 肖国樱；

【作者基本信息】 湖南农业大学 ， 植物学， 2010， 博士

【摘要】 以籼爪亚种间杂交稻产生的重组自交系群体RIL47以及从中筛选获得的耐高温和高温敏感株系为材料,通过抽穗扬花期高温处理和自然温度对比试验,从高温对群体结实率影响、不同耐热性材料的生理物质含量动态变化、高温相关的QTL定位以及高温相关基因的分离和分析等方面,对籼爪重组自交系结实率对高温敏感的生理与分子机理进行了初步研究,获得如下研究结果：(1)重组自交系群体RIL47(107个株系)在自然温度下结实率表现正常,且群体结实率呈正态分布,高温使该群体结实率极显著下降；以热害指数为主要筛选指标,从该群体中获得07C1619、07C1590、07C1521、07C1706、07C1608等5个耐高温株系和07C1751、07C1710、07C1719等3个高温敏感株系,它们可以作为水稻抗高温相关方面的研究材料。(2)以耐热性不同的水稻株系07C1521和07C1751为材料,对高温和自然温度下穗中植物激素和脯氨酸含量动态变化进行了研究,结果表明,自然温度下随着水稻穗的抽出,穗中玉米素(ZR)、脱落酸(ABA)和游离脯氨酸(Pro)含量呈逐渐减少的趋势,而生长素(IAA)含量在此过程中先降后升再下降；与自然温度相比,抽穗扬花期高温使穗中ZR和Pro含量先升后降,使ABA含量始终增加,而对IAA含量影响较小；自然温度下,耐高温材料穗中的ZR、ABA和Pro含量都显著低于高温敏感材料,且高温下耐高温材料Pro含量变化比高温敏感材料更激烈。(3)以耐高温株系07C1590为材料,进行了高温诱导的基因差异表达研究,获得7个差异片段,其中5个是高温上调序列,2个为下调序列；同源性分析结果显示,e9-H、g6-H、g7-H、i9-H、k4-N等5个片段在mRNA和EST数据库中找到了高度同源的序列,但未找到高度同源蛋白；f9-H片段在EST中找到一个同源性达96.7%的未知功能序列；k7-N与编码NADH脱氢酶K亚基高度同源,通过分析,推测其功能可能与高温引起的水稻育性下降和光氧化胁迫有关。(4)以RIL47的111个株系为作图群体,采用SSR标记,构建了一张由61个SSR标记组成的分子连锁遗传图谱,该图谱覆盖水稻基因组12条染色体,全长2025.0 cM,标记间的平均距离为33.20 cM；偏分离分析结果表明,有43个标记发生显著或极显著偏分离,偏分离比例达到71.0%,其中30个标记偏向亲本43s,13个标记偏向亲本770；通过初步的单标记定位分析,分别检测到与自然温度结实率、高温结实率和结实率下降绝对值连锁的SSR标记若干,可靠性需要进一步验证。更多还原

【Abstract】 In order to explore the physiological and molecular mechanism of high temperature tolerance in indica/javanica recombinant inbreed line, the studies including effect of temperature on seed set, dynamic changes of plant hormones, genes differential expression and quantitative trait loci mapping were conducted by using of population of recombinant inbreed line, named as RIL47, under the treatment of high and natural temperature at flowering stage. The detailed results are as follows:1. The effect of high temperature on seed set of recombinant inbreed line population RIL47 at flowering stage has been studied. The results indicated that the seed set of population RIL47 was normal in the natural environment, but decreased significantly under the high temperature. Five heat tolerant lines (07C1619,07C1590, 07C1521,07C1706 and 07C1608) and three heat sensitive lines (07C1751,07CI710 and 07C1719) were selected from the 107 lines of population RIL47 by heat injured index.2. The endogenous plant hormone and free proline content (Pro) in panicle of line 07C1521 and 07C1751 at flowering stage were studied under different temperature. The results indicated that the contents of ZR, ABA and Pro in panicle were reduced gradually along with development of panicle under the natural temperature, but the contents of IAA in panicle fluctuated as low-high-low pattern. The contents of ZA and Pro in panicle of both lines increased at early stage and then decreased late but the ABA content increased all the time under high temperature. However the effect of high temperature on content of IAA in panicle was small after high temperature trarment. In addition, the contents of ZR, ABA and Pro in high temperature tolerant line 07C1521 were much lower than those in high temperature sensitive line 07C1571 under natural temperature, and the changes of Pro content in line 07C1521 were much more than those in line 07C1571 under high temperature.3. mRNA differential display technique has been used for exploring gene differential expression of 07C1590 treated with different temperature. Seven differentially expressed DN A fragments were obtained, five of them were specially expressed under high temperature, and the rest were specially expressed under natural temperature. Results of homological analysis indicated that:e9-H, g6-H, g7-H, i9-H and k4-N were highly homologous with the sequences in databases of mRNA and EST, but highly homologous sequences were not founded in database of proteins and the function of them could not be defined now. The highly homologous sequence of f9-H was not found in database of mRNA, and a highly homologous sequence was founded in database of EST but the function was not explained. The protein sequence of k7-N was highly homologous with that of NADH dehydrogenase subunit K.4. The whole genome molecular linkage map of SSR markers was constructed by use of 111 lines of recombinant inbred line population RIL47 as a mapping population. The molecular map comprises 61 SSR loci which covered a total distance of 2025.0 cM and the average distance between two loci was 33.20 cM. Among these SSR markers,43 markers (71.0%) exhibited distorted segregation (p<0.05), in which 30 of them leaned to 43S, the rest deviated to 770. Several SSR loci relate to seed set have been found by single marker analysis, but their dependability need to be validated.更多还原