不同品种紫玉米籽粒花青素与主要营养成分的动态比较

选取3种不同基因型紫玉米品种即水果黑糯、黑甜糯631和晋糯20为试验材料，比较了不同品种间灌浆期籽粒种皮颜色变化以及种皮颜色（R、G、B值）与花青素含量的相关性，并分析了灌浆期籽粒花青素和主要营养成分的动态积累。结果表明：籽粒RGB值与花青素含量呈显著负相关（P < 0.05）；随着籽粒的发育，花青素、可溶性总糖和蔗糖含量呈动态变化，变化趋势均为先上升后下降。可溶性总糖和蔗糖含量均在授粉后13 d达到最大值；花青素含量在授粉后25 d达到最大值；可溶性蛋白含量呈下降趋势，支链淀粉和直链淀粉含量呈增加趋势。花青素含量与可溶性总糖、蔗糖和可溶性蛋白极显著负相关（P < 0.05），与淀粉含量极显著正相关（ P < 0.05）。上述结果3个品种表现一致。由此可见，RGB值可作为快速检测花青素含量的指标，另外，授粉后21 ~ 25 d可作为紫玉米最佳采收期。

Dynamic comparison of anthocyanins and main nutrients in different varieties of purple corn

In this study, three different genotypes of purple corn (Zea may L.) including FHN, HN631 and JN20 were used to study the changes in seed coat color and the correlation between seed coat color (R, G and B values) and anthocyanin content among different varieties during grain filling period. The dynamic accumulation of anthocyanins and main nutrients in grains at grain filling stage was analyzed. The results showed that there was a significant negative correlation between RGB value and anthocyanin content (P < 0.05) in all the three varieties. Along with the grain development, the dynamic curves of anthocyanin, total soluble sugar and sucrose contents were similar, both increasing and then decreasing gradually. The contents of the total soluble sugar and sucrose reached the maximum at the 13^th day after pollination, while the anthocyanin content of grains reached the maximum at the 25^th day after pollination. The soluble protein content showed a decreasing trend, while amylopectin and amylose contents showed an increasing trend. The anthocyanin content was negatively correlated with the total soluble sugar, sucrose and soluble protein contents (P < 0.05), while it was positively correlated with the starch content (P < 0.05). In conclusion, RGB value can be used as an effective indicator for detecting anthocyanin content, 21-25 days after pollination can be used as the optimum harvest time of purple corn.