Abstract: To explicit the polymorphism distribution of Wx gene which is the main genes for AC in Zhejiang early indica rice and its influence on AC and RVA, total of 37 early indica rice varieties (lines) were selected as materials to detect the Wx genotype, the amylose content (AC) and RVA profile characteristics, and the effects of different Wx genotypes on AC and RVA profiles in rice and the correlation between AC and RVA were analyzed. The result showed that the AC of Wx^a genotype varieties (lines) presented a medium or high level(23.38%~28.93%), while the AC of Wx^b genotype varieties (lines) presented a low level(11.61%~17.77%). Meanwhile, Wxⁱⁿ genotype wasn't detected in the 37 materials. The RVA profile characteristics were significant related with Wx genetype, and the RVA profile characteristics differed within variety(line) with different Wx genotype background, the SBV of Wx^a genotype was positive while the SBV of Wx^b genotype was negative. According to different Wx genotype, the CPV and BDV of each variety (line) distributed into non-overlapping areas. Wx^a genotype presented a low BDV and a high CSV; While Wx^b genotype presented a high BDV and a low CSV. The correlation of AC and RVA profile characteristics reached extremely significant level when not distinguishing the Wx genotype background, while the correlation of AC and RVA profile characteristics of the variety (line) was not significant within the same Wx genotype. The results can be used to provide a certain strategy to regulate the AC in early indica rice by mediating Wx allelic genes and screen high-quality edible early indica rice based on the RVA profile characteristics.

Key words: early indica rice, Wx genotype, amylose content(AC), RVA profile

摘要： 为明确直链淀粉含量(AC)主要控制基因Wx在浙江早籼稻中的多态性分布及其对稻米AC、RVA谱的影响,本试验以37份早籼稻品种(系)为材料,进行 Wx基因型检测,以及AC及RVA谱特征值测定,分析不同Wx基因型对稻米AC、RVA谱的影响及AC、RVA间的相关性。结果表明,Wx^a基因型品种(系)AC表现为中、高水平(23.38%~28.93%),Wx^b基因型品种AC表现为低水平(11.61%~17.77%),37份材料中未检出Wxⁱⁿ基因型;RVA谱特征值与Wx基因型高度相关,不同Wx基因型背景下各品种(系)RVA谱特征值差异明显,且Wx^a基因型消减值为正值,Wx^b基因型消减值为负值。Wx基因型不同的各品种(系)的冷胶粘度(CPV)和崩解值(BDV)分布在不重叠的区间。Wx^a基因型表现出崩解值小、回复值大的特性,Wx^b基因型表现出崩解值大、回复值小的特性。在不区分Wx基因型的条件下,AC与RVA谱特征值极显著相关,在相同Wx基因型内,品种(系)间AC的变化与RVA谱特征值的相关性并不明显。本研究结果为利用Wx等位基因调控早籼稻AC含量,并根据RVA谱特征值筛选优质食用早籼稻提供了一定的理论参考。

关键词: 早籼稻, Wx基因型, 直链淀粉含量(AC), 淀粉粘滞性(RVA)谱