播期和种植密度对水稻“中浙优1号”RVA特征值和米饭质地的影响

以水稻组合"中浙优1号"为材料,研究播期和种植密度对其常规品质、RVA特征值和米饭质地的影响。结果表明,不同播期和密度处理下,供试样品的整精米率、垩白度、直链淀粉、RVA的消减值和回复值以及米饭硬度共6项指标差异达显著水平。不同播期试验中,播期Ⅲ(6/15)稻米的整精米率最高;播期Ⅰ(6/5)、Ⅱ(6/10)样品的淀粉RVA特征曲线接近,且其峰值粘度明显高于后3个播期;后3个播期淀粉RVA特征谱接近;播期Ⅰ、Ⅱ米饭粘性较高,且播期Ⅱ的硬度最小。不同种植密度处理试验中,种植密度Ⅱ(13.5万丛/hm2)处理的整精米率最低,种植密度Ⅴ(27万丛/hm2)的整精米率最高,两者差异达6.1%;种植密度Ⅴ处理的RVA的消减值、回复值和米饭质地的硬度均为最小。"中浙优1号"在温州地区可于6月10日左右播种,并选择27万丛/hm2的种植密度,其RVA的消减值约-50 RVU,米饭硬度约0.5 kg,粘性约20.0 g.mm2,米饭食味品质较好且米饭冷后不易回生。

Effect of Sowing Date and Plant Density on Starch RVA and Texture Properties in Rice "Zhongzheyou 1"

Based on the experiment on hybrid rice "Zhongzheyou 1" with different sowing dates and planting densities,the effects of sowing date and planting density on rice general quality,RVA characters and texture of cooked rice were studied.The results showed that head milled rice rate,chalkiness percent,amylose content,setback of RVA,consistency and hardness of cooked rice were significantly different between different sowing date and planting density treatments.Among different sowing date treatments,head milled rice rate was the highest for sowing Ⅲ(15th June).The RVA character values of amylase were same for sowingⅠ(5th June),Ⅱ(10th June),and their RVA peak viscosity values were higher than that of corresponding values for sowing Ⅰ,Ⅱ,Ⅲ.The adhesiveness values of cooked rice for sowing Ⅰ,Ⅱ were higher than that of corresponding values for sowing Ⅲ,Ⅳ,Ⅴ.The hardness of cooked rice for sowing Ⅱ was the lowest.Among different planting density treatments,the head milled rice rate was the lowest for planting density Ⅱ(13.5×104 plants/hm2),and the highest for planting density Ⅴ(27×104 plants/hm2),the difference between them was 6.1%.The RVA setback,consistency and hardness of cooked rice were lowest for planting density Ⅴ,respectively.In Wenzhou,the rice variety "Zhongzheyou 1" could be sowed in tenth June,planting density could be chosen at 27 ×104 plants/hm2,the RVA setback value was-50 RVU,the hardness and adhesiveness of cooked rice were 0.5 kg and 20 g.mm2 respectively,the eating quality was better and not retrogradation.