灌浆结实期温度对水稻产量和品质形成的影响

Effects of air temperature during rice grain-filling period on the formation of rice grain yield and its quality

灌浆结实期是水稻产量和品质形成的关键时期,该时期温度对水稻籽粒灌浆具有显著的影响。随着全球气候趋暖以及极端天气频发,温度胁迫下籽粒灌浆和稻米品质的响应特征及其生理生化机制是目前稻作研究的热点之一。本文以灌浆结实期温度为切入点,对水稻产量和品质形成的适宜温度与温度影响时段以及温度胁迫下水稻生理生化特征等方面进行了梳理。灌浆初期(齐穗后20d)是温度影响水稻产量和品质形成的关键时期,适温(21～26℃)有利于水稻灌浆和淀粉的充实与沉积,过高或过低温度均不利于提高水稻产量和品质。温度胁迫下,水稻生理生化活性下降,光合功能降低,抗逆性减弱,干物质积累和运转受抑,从而造成产量下降及品质变劣。这些可能为水稻优质高产栽培和灌浆结实期温度研究提供一定的参考。

The grain-filling period of rice is critical to the formation of rice grain yield and its quality, whereas the air temperature in this period has significant effects on the rice grain-filling. With the global warming and the increasing frequency and amplitude of extreme temperature events, to study the response characteristics of rice grain-filling and grain quality to temperature stress and the related physiological and biochemical mechanisms is one of the research hotspots in rice cultivation. Taking the air temperature during rice grain-filling as the cut-in point, this paper discussed the appropriate temperature for the formation of rice grain yield and its quality, the crit- ical period affected by temperature, and the physiological and biochemical characteristics of rice under temperature stress. The key stage the temperature affected the rice grain yield and its qual- ity was the early period of grain-filling （20 days after full heading）. The optimum temperature, 21-26 ℃, was conducive to the enrichment and deposition of starch in rice grain, while too high or too low temperature was unbeneficial to the grain yield and its quality. Under temperature stress, the physiological and biochemical activities of rice decreased, its photosynthetic functions declined, resistance to adversity lowered, and dry matter accumulation and translocation were re- strained, resulting in the decline of rice production and the deterioration of rice grain quality. These findings could provide reference for the rice cultivation of high yield and high quality and the research of the temperature in rice grain-filling period.