温度对亚种间杂种花粉育性的影响

Effect of Temperature on Pollen Fertility in Inter-Subspecific Rice Hybrids

以 17个不同类型的籼、粳、爪哇型品种及其杂种为材料 ,通过分期播种 ,研究了温度变化对花粉育性的影响。结果表明 ,当花粉母细胞减数分裂期的日平均气温低于 2 2～ 2 3℃时 ,亚种间杂种的花粉育性显著降低 ,不同组合花粉育性存在明显差异 ,而品种间杂种和常规品种的花粉育性受影响较小 ;当花粉母细胞减数分裂期的日平均气温低于 2 0℃时 ,常规品种和品种间杂种的花粉发育也受到不同程度的影响 ,不同品种与组合间存在差异。花粉母细胞减数分裂期的日平均温度与花粉育性的相关性分析表明 ,温度与花粉育性呈显著正相关 ,亚种间杂种与常规品种的相关系数存在极显著差异。说明减数分裂期的花粉育性受温度影响 ,温度对亚种间杂种花粉育性的影响较常规品种大。

Seventeen rice cultivars and hybrids in different types (indica, japonica, javanica, indica hybrid, japonica hybrid and inter subspecific hybrid ) were evaluated to determine the effect of temperature on pollen fertility. Results showed that the pollen fertility of inter subspecific hybrids was greatly reduced at miosis stage when the average daily temperature dropped to 22.0-23.0℃, and the extent of pollen fertility reduction varied greatly in different hybrids. However, the pollen fertility reduction of indica and japanica hybrids and conventional cultivars was not obvious under the same temperature conditions. When the average daily temperature dropped to 20℃, pollen development of conventional cultivars and hybrids was also affected. Correlation analysis revealed that there existed positive correlation between pollen fertility and average daily temperature. The significant difference(P<0.01) was also detected between the two correlation coefficients: Inter subspecific hybrids and conventional cultivars. Temperature at miosis stage was a key factor to pollen development, and the pollen fertility of inter subspecific hybrids was more sensitive to low temperature than that of conventional variety.