孕穗抽穗期低温处理对黑龙江省主栽水稻品种结实率的影响

选取黑龙江省4个耐冷性不同的水稻品种,应用人工气候室在水稻孕穗抽穗期进行不同低温强度、不同持续时间(2008年)、不同昼夜变温(2009年)处理的低温试验,通过观测比较水稻结实率,分析主栽品种的耐冷性差异,探索障碍型冷害的温度指标及不同昼夜低温形式对水稻结实率的影响。结果表明,品种间对低温表现出不同的耐冷性,在15℃低温下处理8d,空育131的结实率为87%,表现的耐冷性最强,龙稻3和龙稻7次之,而垦稻12的结实率为61.5%,耐冷性最弱;在4～8d的低温处理下,空育131孕穗抽穗期障碍型冷害发生的温度为15℃,龙稻3和龙稻7为16℃,垦稻12为17℃左右;在日积温(15℃)相同的低温处理下,昼、夜持续15℃低温,即水稻始终处于受害温度下的结实率均值低至74.3%,发生了严重的障碍型冷害;昼夜有温差变化,即部分时段水稻处于非受害温度下的结实率均值在79.5%～82.4%,障碍型冷害程度显著下降。

Effect of Low Temperature at Heading Stage on Seed Setting Rate of Major Rice Varieties in Heilongjiang Province

In order to reveal the effect of cold damage to rice setting rate, the cold-resistant experiment was conducted with artificial climate chamber in Heilongjiang province, four major rice varieties with different cold-resistant was se- lected. The results showed that the setting rate of Kongyul 31 was 87% with strongest cold resistance after treatment of 8 days under 15~C, following by Longdao3 and Longdao7, and Kendaol2 was 61.5% with slight cold resistant. The temperature of sterile type cold damage of Kongyu 131 was 15~C at heading stage, after the treatment from 4 to 8 days, following by Longdao 3 and Longdao 7（ 16~C ）, and Kendao 12（ 17~C ）. The setting rate of all rice verities reduced to 74. 3% with same accumulated temperature in one day （ 15°C ）. So the sterile type cool injury was severe for rice that was consistently in low temperature. Diurnal temperature variation reduced the setting rate from 79.5% to 82.4% , namely sterile type cold damage was weaker than that in normal temperature during partial period.