太湖地区晚粳地方种稻米RVA谱特征多样性分析

利用50年代征集的368份太湖地区晚粳稻地方种资源材料（部分种质资源名见表1），系统测定与分析了其稻米RVA谱特征并对其多样性进行了测算。结果表明，这些种质资源的稻米RVA谱曲线特征分化明显，种质间差异极显著，呈现从籼性到糯性连续变化的特征，形成4种特征类群（见图2）。绝大多数种质（约51.9%）RVA谱的消减值在300~1 000 cP，属于典型的粳稻品种，为A类型；少量种质（如大红稻、早日黄稻、上海青、苏州青、慢红谷等）具有糯性淀粉RVA谱特征，为C类型；一些种质（如金谷黄、慢白稻、粗营洋晚稻、细叠谷、立更青）表现典型的籼稻淀粉RVA谱特征（D类型）；部分种质具有优质的RVA谱特征，即消减为负值（如天下第一种、大青种、黄谷大稻头、摇矮子、余山种等），表明种质的淀粉性质存在明显的差异。各特征值的表型遗传多样性指数均大于1，其中崩解值的遗传多样性指数达2.04。RVA谱各特征值间显著相关，并可用崩解值、消减值2个指标来简化定量描述稻米RVA谱的特征。

Analysis of RVA Profile Diversity in Local Late JaponicaRice at Taihu Lake Area

The RVA profile is one of the key characters in evaluating the pasting property of the rice starch,and has been a primary index for improving the taste quality the rice.While the assessment of the local rice resource has always been the important part of the genetic improvement of crop,the research on the diversity of the RVA profile among the local rice resources can offer a basis for the further utilization of the local resources.In this paper,368 late japonica rice cultivars in Taihu Lake area collected around 1950s were employed to performe the RVA profiles.The results showed that the rice starch RVA profile was different among tested cultivars.And the RVA parameters of different materials were also found significantly different from each other,exhibiting continuous variation from indica type to glutinous type,which consequently formed four groups.The setback viscosity value of a large portion of the local germplasm(about 51.9% in all samples)ranged from 300 to 1 000 cP.This portion of the materials thus fallen into typical japonica cultivar,and the corresponding RVA profile belonged to the category A.A few germplasm(such as Dahongdao,Zaorihuangdao,Shanghaiqing,Suzhouqing,Manghonggu)had characteristic RVA profile same as that of glutinous cultivars,the corresponding RVA profile was the category C.While some RVA profiles of other germplasm(such as Jinguhuang,Manbaidao,Cuyingyangwandao,Xidiegu,Ligengqing)were similar to that of typical indica cultivar,and corresponded to the category D.In the sampled cultivars,some of which(such as Tianxiadiyizhong,Daqingzhong,Huanggudadaotou,Yaoaizi and Yushanzhong)had RVA profile of cultivars with good quality,namely,the setback value was negative.The RVA profiles of Taihu lake area local cultivars indicated there were significant diversities in rice starch quality.Further more,the generalized heritability diversity index of every characteristic value was calculated and all of indices were more than 1,among them that of breakdown reached to 2.06.Correlation analysis showed that characteristic values of RVA profile were correlated with each other,and the rice RVA profile characteristics could be described quantitatively by breakdown and setback.