灌浆结实期遮光对糯玉米籽粒产量与淀粉品质的影响

摘要

利用遮阳棚设置不同程度遮光处理,探索了结实期遮光对2个糯玉米品种籽粒产量及淀粉品质的影响.结果表明:遮光处理使糯玉米产量降低且因基因型不同而有差异;遮光处理使糯玉米淀粉的峰值黏度、谷值黏度和终值黏度下降;遮光30%处理显著降低了苏玉糯5号的糊化温度,却使渝糯7号的糊化温度显著增加;遮光处理导致淀粉粒平均直径及大淀粉粒(直径>17 μm)的比例降低;遮光处理对糯玉米淀粉的峰值指数、热晗值及终值温度影响不显著,却提高了回生值及回生热焓值;遮光处理提高了糯玉米淀粉的碘结合力,但这种效应随光照强度的降低而减弱.%Awnings were used to set up two different shading treatments (30% shading, and 50% shading), and the effects of shading treatment at seed-setting stage on the yield and starch quality of waxy maize varieties Suyunuo 5 and Yunuo 7 were studied.The results showed that the seed yield of waxy maize was reduced by shading treatment, and the yield reduction rate was different between 2 maize genotypes.Shading treatment caused the decrease in peak viscosity, trough viscosity and final viscosity of waxy maize starch.The treatment of 30% shading significantly reduced the pasting temperature of Suyunuo 5, while it significantly increased the pasting temperature of Yunuo 7.Shading treatment led to the decline in both average diameter of starch granules and proportion of large starch granules (diameter > 17 μm).Shading treatment had no significant influence on the peak index, gelatinization enthalpy and conclusion temperature of waxy maize starch, but it increased the retrogradation percentage and retrogradation enthalpy of waxy maize starch.Shading treatment enhanced the iodine binding force of waxy maize starch, but this effect was weakened with the reduction in light intensity.