糯玉米自交系籽粒淀粉黏度性状的相关和聚类分析

Correlation and cluster analysis of starch pasting characteristics of waxy corn inbred lines

以129个糯玉米自交系为供试材料,对糯玉米籽粒淀粉RVA黏度性状进行相关和聚类分析。结果表明:①不同糯玉米自交系的7个RVA黏度性状均呈极显著差异,说明供试自交系间淀粉黏度性状存在较大变异。②峰值黏度、谷值黏度和终值黏度3个性状之间,糊化温度和糊化时间2个性状之间均呈极显著正相关,且相关系数均大于0.7。峰值黏度、谷值黏度、终值黏度3个性状与糊化温度、糊化时间2个性状之间多数呈负相关关系,且相关密切程度不高。崩解值和回复值2个性状与峰值黏度、谷值黏度、终值黏度3个性状之间均呈正相关关系,崩解值与糊化温度、糊化时间均呈极显著负相关,回复值与糊化温度、糊化时间则呈极显著正相关。③129个自交系可根据淀粉黏度性状聚为3类,3类自交系的个数分别为77、24和28。各类之间的差异主要反映在黏度值的大小上。第Ⅰ类自交系黏度较大,但类内变异系数较小;第Ⅱ类自交系黏度较小,但类内变异系数较大;第Ⅲ类自交系则介于上述两类之间。

129 waxy corn inbred lines were selected as the tested materials and correlation and cluster analysis on these inbreds with the RVA pasting characteristics were generated. The results were as follows： ① Seven RVA pasting characteristics were all very significant among different inbreds, which indicated the tested inbred lines had great variation in starch pasting characteristics. ② The very significant positive correlation was found among peak viscosity, trough viscosity and final viscosity, and pasting temperature and peak time also had highly significant positive correlation. The correlation coefficients were all greater than 0.7, which showed that the correlation of these traits was very close. Peak viscosity, trough viscosity and final viscosity were negatively correlated with pasting temperature and peak time, hut the related level was not high. Breakdown and setback were positively correlated with peak viscosity, trough viscosity and final viscosity, but the breakdown was negatively correlated with pasting temperature and peak time at a very significant level while setback showed significantly positive correlation with them. ③ 129 inbred lines were clustered into three categories based on seven starch pasting characteristics; the number of inbred lines of each category was 77, 24 and 28 respectively. The difference between categories was primarily reflected in the value of viscosity and variation within each category. Inbreds in category Ⅰ had a big viscosity value and a small coefficient of variation within category. Inhreds in category Ⅱ had a small viscosity value hut a high coefficient of variation within category. Inbreds in category Ⅲ were somewhere between category Ⅰ and Ⅱ.