Abstract:

Under the condition of intelligent artificial climate chamber, the effects of extreme high temperature on the seed setting rate of hybrid rice and it's fertilizer-water regulation were studied with five hybrid rice combinations as tested materials. The results showed that the average daily temperature above 33℃ at booting stage and heading stage had significant effect on the seed setting rate of rice. When the temperature was above 38℃, the seed setting rate dropped sharply. At the heading stage, when the temperature reached 38℃, the seed setting rate of the tested varieties was below 10%. The effect of high temperature on booting stage was significantly smaller than that at heading stage. Under the conditions of average daily temperature of 33℃ at booting stage, the yield loss of the tested varieties was less than 10%, while 33℃ at heading stage, the yield loss was about 65%. Under 38℃ conditions, the yield loss of high temperature at booting stage and heading stage was about 80% and 90% respectively. There were significantly or extremely significantly positive correlation between seed setting rate and plant chlorophyll content and soil relative water capacity under the condition of high temperature. Increasing the nutrient level of the plant and keeping the shallow water layer in the paddy field could significantly alleviate the yield loss caused by high temperature.

Key words: extreme high temperature, hybrid rice, fertilizer-water regulation, yield loss

摘要：

以5个杂交中稻组合为材料,在智能人工气候室条件下,研究了极端高温对杂交中稻结实率的影响与肥水调控效果。结果表明,孕穗期和抽穗期日均温33℃以上对结实率的影响显著,38℃以上时结实率急剧下降,抽穗期遇38℃高温,参试品种的结实率均在10%以下;孕穗期受高温影响明显比抽穗期小,33℃条件下,孕穗期高温产量损失在10%以内,抽穗期高温产量损失65%左右,38℃条件下孕穗期和抽穗期高温产量损失分别在80%和90%左右。在高温条件下,植株叶绿素含量和土壤相对持水量与结实率呈显著或极显著正相关,提高植株的营养水平和稻田保持浅水层,有显著的缓解高温造成的产量损失的作用。

关键词: 极端高温, 杂交水稻, 肥水调控, 产量损失