调整播期可以改变水稻生长发育中的环境气候条件,对于充分利用自然资源、调节水稻生育进程及提升产量和品质具有重要意义。为明确南方双季晚籼稻优质丰产与温光资源相适应的播种期,本研究选用万象优华占、象牙香珍和美香占2号等3个晚籼稻品种为试验材料,设置6月10日、6月20日、6月30日共3个播期,研究播期对双季晚籼稻品种温光资源利用、产量及稻米品质的影响。结果表明,随着播期推迟,供试品种在不同生育阶段日均温度和有效积温、全生育期和齐穗至成熟期阶段的日照时数均呈递减趋势,而全生育期天数无明显变化;产量以6月20日播种的最高,早播（6月10日）会导致显著减产,而晚播（6月30日）虽然也会导致减产,但差异不显著;随播期推迟,晚籼稻品种加工品质、外观品质和蒸煮品质变优,但不利于改善食味品质,对营养品质无显著影响。在南方双季晚籼稻实际生产中,不建议早播,应根据品种不同进行适期播种或适当晚播,能使水稻更合理有效地利用温光资源,有利于协调水稻高产和品质提升。

Adjusting the sowing date can change the environmental and climatic conditions in the growth and development of rice, which is important for making full use of natural resources, regulating the growth process, and improving yield and quality of rice. It is crucial to clarify the optimal sowing date for double-season late indica rice with high quality and yield in southern China, according to temperature and light resources. The three late-season indica rice varieties, Wanxiangyouhuazhan, Xiangyaxiangzhen and Meixiangzhan 2, were selected as test materials to study the effects of sowing dates on the utilization of temperature and light resources, yield and quality of double-cropping late indica rice varieties. The results showed that, with delayed sowing date, the average daily temperature and effective cumulative temperature, the sunshine hours at different growth stages, and the whole-growth period to maturity all showed a decreasing trend, while the whole-growth period did not change significantly. The grain yield maximized in the treatment of sowing on June 20, early sowing （June 10）would cause a significant reduction in yield, while late sowing （June 30） would also cause a reduction in yield, but the difference was not significant. With the delayed sowing date, the processing quality, appearance quality and cooking quality of late indica varieties become better, but it was not conducive to improving the eating quality and had no significant effect on the nutritional quality. In the actual production of double-season late indica rice in the southern China, early sowing is not recommended. It should be sown at the right time or appropriately late time according to the variety, which can contribute to more rational and effective use of temperature and light resources, thereby strike a balance between high yield and quality improvement of rice.