播期对麦茬直播粳稻产量及品质的影响

  【目的】探讨麦后直播条件下播期对不同熟期类型水稻品种产量及品质的影响。【方法】以3种熟期类型的6个水稻品种为材料，通过分期播种试验，对不同播期条件下直播稻产量形成及品质性状进行分析。【结果】随着播期的推迟，3种熟期类型水稻品种产量均显著下降，且变化程度不一；产量的下降主要在于每穗颖花数和结实率的降低，穗数和千粒重变化不大。不同播期条件下直播稻的主要品质性状的变化规律在品种类型间有所异同：随着播期的推迟，产生相同效应的是外观品质和蒸煮与食味品质，但变化趋势不一，外观品质均呈变优的趋势，蒸煮与食味品质则呈变劣的趋势；产生不同效应的是加工品质和营养品质，推迟播期使中熟中粳和迟熟中粳类型品种的加工品质变优而营养品质变劣，早熟晚粳类型品种的加工品质变劣而营养品质变优。【结论】直播稻在前茬腾茬时间允许的条件下尽可能早播易取得高产，且可以改善稻米的蒸煮与食味品质，但降低了外观品质，播期对加工品质和营养品质的影响因品种熟期类型而异。

Effects of Sowing Date on Yield and Quality of Direct Seeding Rice of Different Types and Varieties

【Objective】 The objective of the study is to elucidate the effect of sowing date on grain yield and its quality of direct seeding rice. 【Method】 Taking six representative rice cultivars of three types as experimental materials, the yield formation and main rice quality traits of direct seeding rice growing under the conditions of different sowing date were analyzed.【Result】The results showed that along with the delayed sowing date, the yields of three types of rice cultivars were all significantly decreased, and the changing degree was different; the yield decreasing caused by the decline of spikelets per panicle and filled grain percentage, panicles and 1000-grain weight had a little change. The law of changing of main direct seeding rice quality traits between different types under the conditions of different sowing date showed some similarities and differences. Along with the delayed sowing date, the appearance quality and cooking and eating quality had the same effect, but the trend was different, appearance quality became better while cooking and eating quality became worse. Milling quality and nutrient quality had different effects, milling quality of the type of medium-maturing and late-maturing medium japonica rice became better but worse the nutrient quality, milling quality of the type of early-maturing late japonica rice became worse but better the nutrient quality. 【Conclusion】 The direct seeding rice should be sowed as early as the time for harvesting the previous crop allows to attain high yield and improve cooking and eating quality, but reduce the appearance quality. Effects of sowing date on milling quality and nutrient quality were different because of types and varieties.