不同生育期高温对玉米子粒品质及淀粉糊化特性的影响

Effects of High Temperature at Different Stages on Kernel Quality and Starch Pasting Properties of Maize

以玉米杂交种隆平206与秦龙14为试材,分别在开花期和子粒灌浆期进行高温处理,研究不同生育期高温对玉米穗部性状、子粒品质与淀粉糊化特性的影响。结果表明,开花期与子粒灌浆期高温处理均显著降低秦龙14的子粒行数、行粒数,其中,开花期秦龙14高温处理败育;对隆平206无显著影响,说明隆平206子粒形成过程中耐高温较强。与对照相比,高温显著增加两个品种玉米子粒蛋白质含量,降低子粒脂肪与淀粉含量;品种间比较,高温对秦龙14品质的影响较隆平206大。隆平206不同生育期高温处理比较,灌浆期高温对子粒脂肪含量影响较大,蛋白质含量次之,淀粉含量相对较小,两个高温处理子粒淀粉峰值黏度、低谷黏度、最终黏度与糊化温度显著高于对照;灌浆期高温处理糊化参数的升幅较开花期高温处理大。玉米生育后期高温对玉米子粒品质及糊化特性有显著影响,灌浆期高温较开花期高温对玉米子粒品质的影响较大。开花期高温对玉米子粒育性影响较大,灌浆期高温主要影响玉米子粒品质。

In order to investigate the effects of high temperature on kernel quality and starch pasting properties of maize, cultivars Longping206 and Qinlong14, were used with heat stress at flowering stage and kernel filling stage by plant growth chamber. Ear characters, content of main chemical components in kernel and parameters for starch gelatinization were examined. The results showed that the number of rows and kernels per row reduced significantly in heat stress of Qinlong14, but changed slightly in heat stress of Longping206 with no significant difference to con- trol. The protein contents in kernel were enhanced significantly, but the contents of fat and starch in kernel reduced greatly under high temperature. The parameters of Longping206 varied less than those of Qinlongl4. The order of kernel quality（Longping206） influenced by high temperature was as follow： protein content 〉 fat content 〉 starch content. The peak viscosity, through viscosity, final viscosity and pasting temperature increased significantly in heat stress compared to control. Heat stress in kernel filling stage had larger increasing amplitude of those compared to heat stress in flowering stage. It showed that high temperature had a significant effect on kernel quality and pasting properties of maize at the late growth stage. Effects of heat stress in kernel filling on kernel quality were greater than that in heat stress in flowering. The influence of high temperature in flowering stage on kernel fertility was great, and high temperature in kernel filling stage was more influence on the quality of maize.