开花期剪叶和疏花对‘宁粳1号’和‘镇稻88’稻米淀粉RVA谱特征值的影响

The Effect of Leaf-cutting and Spikelet-thinning on the Starch RVA Profile Characteristics of the Japonica Rice ‘Ningjing 1' and ‘Zhendao 88'

为了确定源和库的改变及其平衡对稻米淀粉RVA谱特征值的影响,通过不同剪叶和疏花处理,研究其与稻米淀粉RVA谱特征值的关系。以粳稻品种‘宁粳1号’和‘镇稻88’为材料,在水稻开花期采用剪叶和疏花处理方法调控单茎叶面积和颖花数的差异,研究其对稻米淀粉RVA谱特征值的影响。结果表明,随剪叶数量增加,叶花比下降,峰值黏度、热浆黏度和冷胶粘度显著降低;随疏花数量增多,叶花比提高,峰值黏度、热浆黏度和冷胶粘度显著上升;崩解值、消减值和回复值变化较复杂。本研究还发现了叶花比在一定范围之前,峰值黏度、热浆黏度和冷胶粘度变化较快,当叶花比超过一定范围继续增大时峰值黏度、热浆黏度和冷胶粘度变化趋缓甚至不再变化。剪叶和疏花处理以及叶花比与稻米淀粉RVA谱特征值关系显著,研究初步明确了3.0左右为叶花比影响粳米稻米淀粉RVA谱特征值的临界值,其结果可供粳稻优质育种和栽培参考。

To determine the effects of dynamic changes of the Source-Sink on the RVA profile characteristics of starch, different leaf-cutting and spikelet-thinning treatments were conducted to investigate the relationship between Source-Sink and RAV properties. Japonica rice varieties ＇Ningjing 1＇ and ＇Zhendao 88＇ were used in this study. Leaf-cutting and spikelet-thinning treatments were conducted at the rice flowering stage in order to obtain the regulated leaf areas of single stem and differentiated numbers of spikelets per panicle. Effects of leaf-cutting and spikelet-thinning on the starch RVA profile characteristics were evaluated. The results indicated that as the number of the cut leaves increasing, the leaf-spikelet ratio decreased and Pkv, Hpv and cpv were significantly reduced. Furthermore, spikelet-thinning induces the increased leaf-spikelet ratio and the significant increases of Pkv, Hpv and cpv. Pkv, Hpv and cpv were the leaf-spikelet ratio （〈3.0 cm2/spikelet） and no changed rapidly within a Certain range of significant changes were observed when the leaf-spikelet ratios were greater than 3.0 cm2/spikelet. Leaf-cutting and spikelet-thinning could significantly affect the the RVA profile characteristics and 3.0 cm2/spikelet could be considered as the critical leaf-spikelet ratio that could affect the RVA profile characteristics. This result would provide a basis for breeding and cultivation of high--quality japonica rice.