温度对长穗颈温敏核不育水稻(Oryza sativa L.)穗颈伸出长度的影响

Effects of temperature on panicle exsertion of TGMS rice with eui gene

以隐性长穗颈温敏核不育水稻(OryzasativaL)长选3S为材料,研究了温度对隐性长穗颈温敏核不育水稻长选3S穗颈伸出长度的影响。结果表明:人工24℃条件下,在始花前第12天至始花前第4天和始花当天至始花后第3天两个时段,穗颈节间伸长速度慢,两者节间日均伸长长度基本一致,但从始花前第4天至始花当天,长选3S穗颈节间伸长速度最快,其节间日均伸长的长度是培矮64S的2.1倍。在敏感期分别进行22、24、26、28℃4种人工温度处理,28℃条件下穗颈节间伸长受阻,出现包颈现象;26～22℃条件下穗颈伸出长度都为正值,不包颈,但穗颈伸出剑叶叶鞘的长度随温度降低而增加。通过对穗颈节间细胞数目和细胞长度的比较分析表明,长选3S穗颈节间的伸长主要是由于细胞分裂和细胞伸长共同作用所致,其中后者作用更显著,且随处理温度的升高,穗颈节间最内和最外层薄壁细胞数目减少,细胞平均长度变短。

Changxuan3 S was thermo-sensitive genic male sterile （TGMS） rice （Oryza sativa L. ） with eui gene selected from Peiai64S irradiated by 350 Gy^60Co γ-ray. To study the effects of temperature on panicle exsertion for Changxuan3S, Changxuan3S was taken as material and Peiai 64S as control. The results showed that the increasing rate of the elongated uppermost internodes was slow from the 12th day preblooming to the 4th day preblooming, and 0day （anthesis） to the 3rd day after anthesis under the condition of constant 24 ℃, the daily mean increasing length had no obviously difference between Changxuan 3S and Peiai64S. But the increasing rate of the elongated uppermost internodes for Changxuan 3S was faster, and was 2.1 times greater than that of Peiai 64S from the 4th day preblooming to 0 day （anthesis）. During the thermo-sensitive period, when Changxuan 3S was treated with the condition of constant 22, 24, 26, 28 ℃, the panicle exsertion was positive number under the treatment 22, 24, 26 ℃, respectively, so that panicle enclosure in Changxuan 3S disappeared, and the lower the temperature treated, the longer the panicle elongation was, while the panicle was enclosed at temperature 28 ℃. Cytological studies on Changxuan 3S showed that the uppermost internodes elongation was due to the increase of cell number and elongation, and the elongation of the later was more significant. But also, the number of outermost and innermost parenchyma cell in uppermost intemodes reduced, and the cell length shortened along with increasing temperatures.