水稻越冬品系的耐冷性鉴定

以4个水稻越冬品系和4个籼稻品种(对照)为材料,检测了低温胁迫条件下水稻幼苗的生理生化特性。结果显示,经低温胁迫,越冬品系的幼苗存活率极显著高于对照品种,幼苗存活率最高的是SW-2(95.31%),最低的是对照品种桂99(1.67%),4个越冬品系平均幼苗存活率比4个对照品种高出71.12个百分点。低温胁迫后越冬品系的相对电导率小于对照品种,黄化幼苗的转绿能力强于对照品种。水稻幼苗在低温胁迫后丙二醛(MDA)含量都有所增加,但越冬品系比对照品种增加的量要少;越冬品系在低温胁迫后超氧化物歧化酶(SOD)相对活性比对照品种要高。因此,越冬品系具有很强的耐低温能力。

Identification of Cold Tolerance of Winter Lines in Rice

The physiological responses of rice seedlings to low temperature stress were tested with four surviving-in-winter(SW)lines or winter lines and four common indica varieties(the controls) as the materials.The results showed that the average seedling survival rate(SSR) of four SW lines under 5 days of low temperature treatment(85.75%) was much higher than that of four control varieties(14.63%) with SW-2 as the highest(95.31%) and Gui 99 as the lowest((1.67)%).Both of the relative conductivity rate(RCR) and the chloroplast pigment degradation rate(CDR) of SW lines were lower than those of the cultivars in control after low temperature stress.The MDA content of rice seedlings would increase under low temperature stress,but the relative increasing amount in the SW lines was much less than that of the control varieties.The SOD relative activity of the SW lines was higher than that of the control varieties in the wake of suffering from chilling stress.Therefore,the winter lines have a very strong cold tolerance.