灌浆成熟期光照强度对早籼稻直链淀粉含量及淀粉RVA谱特性的影响

Effects of light intensity on grain amylose content and starch RVA profile characteristics of early indica rice during grain-filling stage

选择浙江省推广种植的直链淀粉含量差异较大的3个早籼稻品种,通过5个不同的遮光处理,研究了灌浆成熟期光照强度对早籼稻米直链淀粉及其淀粉RVA谱的影响。结果表明,除品种与光强互作对消减值的效应未达显著水平外,品种、光强及其互作效应对直链淀粉含量及淀粉最高黏度、热浆黏度、崩解值、冷胶黏度和消减值的效应均达显著或极显著水平。灌浆成熟期光照强度对淀粉最高黏度和冷胶黏度的影响最大,对热胶黏度、崩解值和直链淀粉含量的影响也较大,而对直链淀粉含量和消减值的影响则相对较小。最高黏度和崩解值均随着光照强度的下降而明显下降,稻米蒸煮食味品质显著降低。

A field experiment was conducted using three early indica rice varieties with different grain amylase content to study the effects of light intensity on grain amylase content and starch RVA profile characteristics during grain-filling stage. The results showed that effects of the variety, light intensity, and their interactionon amylase content, and starch peak viscosity, hot paste viscosity, breakdown, cool paste viscosity, and setback were all significant except for effects of the interaction of variety and light intensity on the setback. The effects of light intensity on peak viscosity and cool paste viscosity were the largest, effects of light intensity on hot paste viscosity was larger, but effects of light intensity on amylase content and setback was smaller. Moreover, peak viscosity and breakdown were significantly reduced as increasing light intensity, which resulting in significant decline in rice cooking and eating quality.