水稻对减数分裂期高温胁迫的生理响应

Physiological Responses of Rice to High Temperature Stress during Meiosis Stage

以水稻耐热品系996、热敏感品系4628为材料,在减数分裂期进行高温处理,以同期自然温度为对照,研究减数分裂期高温对水稻花粉活力、花药开裂、受精率、结实性状及剑叶生理特性的影响。结果表明,高温处理显著降低了花粉活力、花药开裂系数、受精率、结实率,热敏感品系4628下降幅度大于耐热品系996;高温处理降低了热敏感品系4628米粒粒宽,增加了长宽比,对耐热品系996无显著影响;高温下剑叶叶绿素含量、SOD活性、POD活性降低,而MDA含量和相对电导率增加,热敏感品系4628变化幅度大于耐热品系996。

The heat-tolerant rice line 996 and the heat-sensitive rice line 4628 were used to be treated with the high temperature of 37℃（ 09： 00 ~ 17： 00） /30℃（ 17： 00 ~ 09： 00） for seven days during the meiosis stage. The effects of high temperature stress during the meiosis stage were studied on pollen vigor,anther dehiscence,fertilization rate,seed-setting characters and the physiological characteristics of flag leaf in rice. The results showed that high temperature treatments decreased significantly pollen vigor,anther dehiscence,fertilization rate and seed-setting rate and the decreasing extent of the heat-sensitive 4628 was greater than that of the heat-tolerant 996. For the heatsensitive 4628,the grain width was also significantly decreased so that the grain length-width ratio was increased.Under high temperature conditions,the chlorophyll content and activities of SOD and POD were decreased but the MDA content and relative conductivity were increased in flag leaves,and the changing scope of the heat-sensitive4628 was much greater than that of the heat-tolerant 996.