2种不同Wx等位基因型水稻粒质量和蒸煮食味品质的差异

摘要

以携带Wxmq基因的宁0145为母本,携带Wxb基因的武运粳21为父本构建的F3和F4群体为材料,利用分子标记对群体进行基因型分类,测定籽粒千粒质量、直链淀粉含量、胶稠度及RVA谱特征值等性状,分析不同Wx等位基因型各性状值的差异.结果表明:Wxmq Wxmq与Wxb Wxb基因型间千粒质量和稻米蒸煮食味品质性状的差异均达到显著水平,其中Wxb Wxb基因型的稻米千粒质量、直链淀粉含量、胶稠度、热浆粘度和冷胶粘度均大于Wxmq Wxmq基因型,而崩解值小于Wxmq Wxmq基因型;相关性分析结果表明,籽粒质量与直链淀粉含量呈极显著正相关.对不同基因型的淀粉粒精细结构和淀粉密度的测定结果表明,淀粉密度差异可能是导致千粒质量不同的主要原因.携带Wxmq Wxmq基因型的稻米因具有较低直链淀粉含量、胶稠度、热浆粘度、冷胶粘度、消减值、起浆温度和峰值时间,较高崩解值,而使米饭呈现柔软性和弹性等较好食味品质的特点.%Rice Ning 0145 carrying Wxmq allele and Wuyunjing 21 carrying Wxb allele were used as parents to con-struct the F3 and F4 generations. Through detecting the genotype, measuring the thousand-grain weight ( TGW ) , the value of amylose content ( AC) , gel consistency ( GC) and RVA profile of the F3 and F4 generations, the effects of different Wx alleles on grain weight and eating and cook-ing quality ( ECQ ) were studied. The results show that there were significant differences in TGW and ECQ be-tween different Wx alleles. The thousand-grain weight and the value of amylose content, gel consistency, hot paste viscosity ( HPV) and cool paste viscosity ( CPV) of the rice with Wxb Wxb genotype were greater than those with Wxmq Wxmq , but the value of breakdown value ( BDV) was smaller. A signifi-cant positive correlation was shown between grain weight and amylose content value. The differences in starch density might be responsible for the differences in TGW. Rice with Wxmq Wxmq genotype had a lower value of amylose content, gel consis-tency, hot paste viscosity, cool paste viscosity, setback value, peak time and pasting temperature and a higher breakdown value, which have contributed to the good taste quality represented by softness and elasticity.