抽穗-灌浆期不同低温处理对三江平原水稻主栽品种品质的影响

为了探究低温对水稻抽穗-灌浆期品质的影响，以龙粳29、龙粳31和龙粳46为试验材料，利用人工气候箱对水稻进行日平均气温17 ℃/3 d和16 ℃/5 d的低温试验。通过对低温处理后水稻品质的研究发现:低温导致水稻的糙米率、精米率和整精米率下降，蛋白质含量上升，稻米RVA谱特征参数的最高黏度和热浆黏度降低；2016年低温促进直链淀粉的合成，2017年低温对抽穗-灌浆前期直链淀粉的合成有抑制作用，对灌浆中后期有促进作用；适宜低温会提高强耐冷性品种的食味评分，降低一般耐冷性品种的食味评分；不同低温对不同品种在不同生育期的崩解值、消减值和回复值影响不同，这与水稻RVA谱特征参数的复杂性有关，有待进一步研究。 

Effects of Different Low Temperature Treatments at Heading-filling Stage on Quality of Main Rice Varieties in Sanjiang Plain

To explore effect of low temperature on quality of rice at heading-filling stage，taking Longjing 29，Longjing 31 and Longjing 46 as experimental materials，low temperature tests of daily average temperature of 17 ℃/3 d and 16 ℃/5 d on rice were conducted by using artificial climate chamber.Through study of rice quality after low temperature treatment，it was found that low temperature led to decrease of brown rice rate，milled rice rate and head rice rate，increase of protein content，and decrease of the highest viscosity and hot paste viscosity of RVA characteristic parameters.In 2016，low temperature promoted synthesis of amylose，while in 2017，low temperature inhibited synthesis of amylose at early stage of heading and filling，and promoted synthesis of amylose at middle and late stage of filling.Suitable low temperature could improve taste score of strong cold tolerance varieties and reduce taste score of general cold tolerance varieties.Different low temperatures had different effects on disintegration value，reduction value and recovery value of different varieties at different growth stages，which was related to complexity of RVA spectrum characteristic parameters of rice and need further study.