长江中下游稻区双季晚粳稻产量生理与资源利用效率研究进展

长江中下游稻区是我国水稻主产区,同时又是单、双季稻混作区。目前,随着经济发展和人民生活水平的提高,人们对优质大米,尤其是优质粳米的需求日益增加,因此,在双季稻生产中引入粳稻具有重要的现实意义。本文介绍了长江中下游双季稻的温光资源特性,总结了现有双季晚(籼/粳)稻品种的种植表现,从产量、产量结构、干物质积累、群体动态、生育期、温光利用率、稻米品质等方面比较了长江中下游稻区晚粳与晚籼的可能差异。总体来说,双季晚粳在产量、每穗粒数、结实率、千粒重等方面均显著高于晚籼;前期干物质积累两者无显著差异,但是后期干物质积累量晚粳要高于晚籼,晚粳的灌浆率显著高于晚籼,这预示着双季晚粳具有更高的产量潜力。粳稻比籼稻有着较平稳的茎蘖动态,这使其具有更强的后期光合能力、更高的后期光能利用率;全生育期晚粳比晚籼长,主要体现在推迟抽穗结实,延长结实灌浆期;粳稻全生育期积温和光照时数均显著高于籼稻,粳稻后期叶面积指数大于籼稻,光合势亦高于籼稻,而在生育前期(拔节至抽穗期)两者对温光资源的利用基本相当,因此温光利用率晚粳显著高于晚籼;另外,晚粳的稻米品质要优于晚籼。因此,相对于双季晚籼,双季晚粳具有更高的应用推广价值。

Study on the Physiological Characteristics and Resource Utilization Efficiency of Double Cropping Late Japonica rice in the Middle and Lower Reaches of the Yangtze River

The middle and lower reaches of the Yangtze River is a major rice production areas with single and double rice cropping systems coexisted. With the increasing demand for the high quality rice, applying the japonica rice seems to be a promising choice in double season. In current study, the climate(temperature and solar radiation) conditions of the double season in the middle and lower reaches of the Yangtze River area were summarized. The applied varieties(indica/japonica) were introduced, furthermore, the physio-logical and agronomic performances (the grain yield production, the yield components, the dry-matter accumulation, the dynamics of the tiller and leaf, the growth period, the utilization rate of temperature and solar radiation, and grain quality) between the japonica rice and indica rice in the late season were compared. Generally speaking, the grain yield, grains per panicle and seed setting rate were significantly higher in the late japonica rice than that of late indica rice. The accumulation of dry matter during vegetative stage is not significant different between the japonica rice and indica rice, however, the dry matter accumulation and grain filling rate during ripening stage are greater in japonica varieties than that in indica varieties, these results indicated a greater yield potential in late sea-son japonica varieties than indica ones. In addition, the japonica rice is more stable than indica rice in the dynamic of tiller produc-ing, which will result in a greater photosynthetic capacity during ripening stage, and higher resource utilization, in compared with the late indica rice; a longer growth period was also found in japonica rice than in indica rice, which might result from the delayed head-ing and the extend grain filling stage. For climate resource, the japonica rice accumulated more temperature and sunlight hours than indica rice. Considering the higher leaf area index, greater photosynthetic capacity and shorter jointing to heading period than the late indica rice during the ripening stage, it suggested that the applying the japonica varieties in the late season might improve the temper-ature and solar radiation use efficiency, compared with the traditional option (indica rice). Besides the superiors in grain yield and resource utilization, the grain quality of late japonica rice is better than that of late indica. Therefore, applying the japonica varieties instead of the indica ones in the late season might be an optimum choice in achieving the stable yield and improved grain quality in the middle and lower reaches of the Yangtze River.