【作者】 钟卫华；

【导师】 梁满中； 陈良碧；

【作者基本信息】 湖南师范大学 ， 植物学， 2004， 硕士

【摘要】 隐性长穗颈(elongated-uppermost-internode，简称eui)不育水稻的选育与广泛应用于生产可以从根本上解决不育系包颈现象。有关eui基因的遗传规律等方面已有深入研究，但环境因素对eui基因表达的影响还未见报道。探明这两者之间的关系是将eui基因应用于杂交水稻制种所必须做的极其重要的基础性工作。本文以隐性长穗颈不育水稻长选3S为材料，以培矮64S为对照，研究了温度对穗颈基因表达的影响。主要研究结果如下： (1) 在自然条件下，长选3S穗颈节间的长度与始花当天的日平均温度无关，而与始花前9-20天日平均温度呈负相关，与始花前12-17天(花粉母细胞形成至减数分裂期)日平均温度负相关性最显著。通过对长选3S在始花前进行不同天数人工24℃处理，分析穗颈伸出度与处理天数的关系得知，始花前12-17天(即花粉母细胞形成至减数分裂期)适宜温度处理能够使eui基因充分表达。因此花粉母细胞形成至减数分裂期是隐性长穗颈eui基因表达对温度敏感时期，该基因感温表达具有积温效应，6天的感温效果最佳。 (2) 在eui基因表达对温度最敏感的时期进行22℃、24℃、26℃、28℃四种人工温度处理，通过穗颈伸出度的统计，得知28℃条件下eui基因表达受抑制，22-26℃条件下eui基因可以表达，且穗颈伸出度随温度的降低而增长。 (3) 对长选3S和培矮64S幼穗不同发育时期穗颈节间长度的统计，得出穗颈节间伸长的动态变化规律。即在幼穗分化Ⅶ期前两者穗颈节间伸长无差异，从Ⅶ期始至始花当天长选3S穗颈节间迅速伸长。观察不同发育时期穗颈节间的细胞长度和细胞个数，呈现相同的变化规律，即从Ⅶ期始长选3S穗颈节间细胞迅速伸长，细胞个数增多。 (4) 通过对长选3S和培矮64S定长的穗颈节间细胞个数统计和细胞长度的测量，得出隐性长穗颈不育水稻穗颈节间细胞伸长的空间变化规律。不同温度处理定长穗颈节间的细胞长度的比较也表明，22℃和24℃处理的穗颈节间中部区段细胞长度较26℃和28℃处理的长。自然条件下隐性长穗颈不育水稻长选3S穗颈节间比对照培矮645长18.0 Cm，其纵列外层薄壁细胞和内层薄壁细胞数分别比培矮645多1248个和580个;外层薄壁细胞和内层薄壁细胞平均长度分别比培矮645长23.3 pm和38.3 pm，尤其是中部区段的外层薄壁细胞和内层薄壁细胞分别比对照长24.8 pm和48.7 pm;穗颈节间薄壁细胞的长度由基部区段至中部区段呈突跃式增加，而由中部至顶部区段则呈缓慢减少的趋势。隐性长穗颈温敏核不育水稻穗颈节间伸长是由细胞数目增多和细胞长度增加双重作用所致，其中后者作用更显著。 (5)长选3S不同温度条件下mRNA的比较，以及长选3S与培矮645不同材料mRNA的比较发现，长选3S在24℃条件下mRNA表现出的差异条带有两种类型，一种是特异表达条带，一种是表达加强条带。 (6)不同温度处理后，22℃温度条件下隐性长穗颈不育水稻花粉育性有波动，但波动幅度与培矮645一致，因此说明eui基因对温敏核不育系的育性没有影响。 综上所述，隐性长穗颈不育水稻在大田生产应用时要注意选择适宜的时间段和地域，既保证隐性长穗颈eui基因能够表达又确保其育性不发生变化;在隐性长穗颈eul基因感温的敏感时期若遇到持续高温天气，在抽穗时则可通过适当喷施赤霉素以确保穗颈节伸出。更多还原

【Abstract】 Changxuan 3S was thermo-sensitive male sterile(TGMS) rice with eui gene selected from seeds of Peiai 64S irradiated by 350 Gy60Co Y -ray. To provide science evidence and theory support for exploiting and utilizing TGMS rice Changxuan 3S with eui gene, the correlativity between panicle exsertion of Changxuan 3S and nature temperature was analyzed, and effect of different temperature treatment on eui gene expression was researched, and the cell number and length were analyzed. The main results were as follows:(1) There was a negative correlativity of panicle exsertion and nature temperature at 9-20 days before flowering. And the negative correlativity of panicle exsertion with mean diurnal temperature at 12-17 days(from pollen mother cell formation to meiosis) which was the thermo-sensitive period of eui gene was the most significant before flowering. The analysis showed that eui gene expressed best in feasible temperature for 6 days during the thermo-sensitive period.(2) In the thermo-sensitive period of eui gene, when Changxuan 3S was treated with the condition of constant 22C, 24 C, 26C and 28C respectively, the eui gene could express under the treatment of 22C, 24C and 26C respectively but was inhibited at temperature 28C. And the lower the temperature treated, the longer the panicle exsertion was.(3) The dynamic mutative rule of uppermost internode elongation compared with Peiai 64S was concluded from the statistic of first internode length in different stage. The rule was that the uppermost internode of Changxuan 3S elongated much more from VII stage to flowering day, but had little difference with Peiai 64S before VII stage. The observation of first internode cell length in different stages also made the similarrule which the cell elongated faster from VII stage.(4) The spatial mutative rule of uppermost internode cell elongation of thermo-sensitive rice with eui gene was researched from the cell number statistic and length measure. The result of cell comparison showed that uppermost internode cell length in different temperature treatment was different which the cell length of first internode with the treatment of 22 C and 24 C was longer than that in 26C and 28C. Uppermost internode of Changxuan 3S was 18. 0 cm longer than that of Peiai 64S. And the number of external and internal thin-walled cell were 1 248 and 580 more than those of Peiai 64S respectively, length of these two kinds cell of Changxuan 3S were 23. 3um and 38. 3 u m more than those of Peiai 64S respectively. The length of external and internal thin-walled cell of Changxuan 3S in the middle section of uppermost internode was 24. 8um and 48. 7um longer than those of Peiai 64S extremely. Cell length of Changxuan 3S increased abruptly from group section to middle section, and internal thin-walled cell elongated more extremely. It is, therefore, evident that the uppermost internode elongation of Changxuan 3S is due to the increase of cell numbers and cell elongation, and the effect of later was more obviously.(5) It was found that there were tow kinds of band pattern in mRNA of Changxuan 3S with the treatment of 24C. One kind was the special band and another was the type of strong band.(6) The fertility of Changxuan 3S had a little change after the temperature treatment of 22C during the thermo-sensitive period of eui gene. And this change of fertility was as same as Peiai 64S. So the expression of eui gene could not effect the fertility of Changxuan 3S.更多还原