为探明冬水田区播期对不同熟期直播杂交稻产量和光能利用率的影响,以早熟杂交稻川作优8727、中熟杂交稻辐优838、迟熟杂交稻内6优107为材料,于2019年进行不同播种期（5个播种期分别为3月15日、3月20日、3月25日、3月30日、4月4日）大田试验,研究播种期对不同熟期直播稻产量、产量构成、干物质量、光能利用率的影响。结果表明,播期对川作优8727、内6优107产量和光能利用率影响显著,对辐优838产量和光能利用率影响不显著。随播种期推迟,川作优8727产量和光能利用率呈增加趋势,以4月4日播种的处理产量和光能利用率最高,较高的有效穗数、每穗粒数、干物质量、收获指数是其增产的重要原因;辐优838和内6优107产量和光能利用率呈先升高后下降的趋势,以3月20日播种的处理产量和光能利用率最高,其增产优势主要表现在每穗粒数、结实率、干物质量、收获指数上;与川作优8727相比,辐优838、内6优107产量分别增加14.6%、33.0%,光能利用率分别提高9.0%、20.5%。综上所述,冬水田区早熟杂交稻品种适宜播种期为4月4日,中熟杂交稻品种适宜播种期为3月20日。

A field experiment was conducted to study the effects of sowing dates on grain yield and radiation use efficiency of direct-seeded hybrid rice with different maturity stage at all-time logged-water paddy field in 2019, the early maturity hybrid rice Chuanzuoyou 8727, medium maturity hybrid rice Fuyou 838 and late maturity hybrid rice Nei 6 you 107 as materials. This experiment set up five sowing dates which are March 15th, March 20th, March 25th, March 30th and Apirl 4th. The results showed that, there were significantly differences in grain yield and radiation use efficiency of Chuanzuoyou 8727 and Nei 6 you 107 among five sowing dates, while the difference in grain yield and radiation use efficiency of Fuyou 838 among five sowing dates was relative small. The grain yield and radiation use efficiency of Chuanzuoyou 8727 were increased with the delay of sowing dates, and sowing on Apirl 4th recorded the highest grain yield and radiation use efficiency. The high grain yield was associated with the high panicle number per m², spikelets per panicle, dry matter weight and harvest index. The grain yield and radiation use efficiency of Fuyou 838 and Nei 6 you 107 showed the trend firstly increased and then decreased with the sowing dates delayed, and sowing on March 20th recorded the highest grain yield and radiation use efficiency, its yield increase advantage is mainly reflected in the number of grains per panicle, seed setting rate, dry matter weight and harvest index. Compared with Chuanzuoyou 8727, the grain yield of Fuyou 838 and Nei 6 you 107 were increased by 14.6% and 33.0%, respectively, and the radiation use efficiency were increased by 9.0% and 20.5%, respectively. The results suggested that the suitable sowing date for early maturity hybrid rice cultivar was on Apirl 4th, and for medium and late maturity hybrid rice cultivar was on March 20th at all-time logged-water paddy field in southeast of Sichuan province.