水稻不同生育期温光条件对籽粒充实和米质的影响

水稻分期播种是研究水稻品种温光特性比较便捷的途径，在水稻生产上已经被广泛应用。本试验以协优9308和秀水110为材料，利用分期播种试验分析水稻不同生育阶段的温光条件与籽粒充实和稻米品质之间的关系。研究结果表明，有效积温、日照时数和生育期天数在播种一齐穗期和全生育期均随着播期的延长而逐渐下降，但这些指标在齐穗一成熟期均没有明显的规律性。此外，日平均温度在不同生育阶段的变化趋势不一致，在播种一齐穗期随着播期的延迟而上升，全生育期呈先上升后下降的趋势，而在齐穗一收获期则随着播期的延迟而下降。对协优9308而言，在本试验条件下播种一齐穗期的温光条件对籽粒灌浆、产量及米质的影响均大于齐穗一成熟期，而秀水110的籽粒灌浆速率、产量及米质对不同生育阶段温光条件的响应没有明显的规律性。此外协优9308的产量和恶白度均随着播期的延迟而逐渐减少，整精米率和蛋白质含量则随着播期的延迟而增加，由此看出协优9308比较难同时兼顾高产和优质；秀水110则不同，秀水110的D5处理产量较高，仅次于D3处理，与其相对应的蛋白质含量和整精米率则最高，而恶白度最低。由此笔者认为，只要选择合适的播期，秀水110是可以达到高产优质目的的。

Influence of Temperature and Sunlight Conditions on Rice Grain Filling and Quality in Different Growth Stages

The sowing time experiments with the sowing times in April 15 （D1）, April 30 （D2）, May 15 （D3）, May 30 （D4）, June 14 （D5） and June 15 （D6） were conducted to study the influence of the temperature and light conditions on the rice grain filling and quality, the rice varieties were Xieyou 9308 and Xiushui 110. The results showed that the effec- tive accumulated temperature, sunshine hours and the growth duration decreased as the sowing date delaying in the duration from sowing to heading and the whole growth stage, while no significant regularity was found in the duration from heading to maturity. The daily average temperature changes showed the different trends in the different growth stages. The temperature and illumination conditions in the duration from sowing to heading had more significant impacts on the grain filling rate, yield and quality for variety Xieyou 9308 than that in the duration from heading to maturity, but those differences responding to different growing periods were not obvious for variety Xiushui 110. Furthermore, as the sowing time delayed, the yield and chalkiness degree of Xieyou 9308 decreased, but the head rice rate and protein increased. It was difficult for the variety Xieyou 9308 to get the high yield and quality at same time. For variety Xiushui 110, the yield was higher in the D5 treatment with the highest protein content and head rice rate, and the lowest ehalkiness degree. For variety Xiushui 110 to select appropriate sowing time could receive high yield and quality.