以黄色(特爆2号)、红色(西星赤糯1号)、紫色(紫糯香)和黑色(西星黑糯1号) 4种颜色的玉米为材料,通过徒手切片以及分光光度法,研究了玉米籽粒色素的组成、分布和积累规律。结果显示,西星赤糯1号玉米籽粒色素主要由花色苷和类胡萝卜素构成,花色苷主要存在于果种皮中,类胡萝卜素主要存在于胚与胚乳中;特爆2号玉米籽粒色素主要由类胡萝卜素构成,分布于胚与胚乳中;紫糯香及西星黑糯1号玉米籽粒色素主要由花色苷构成,主要存在于糊粉层中。除西星赤糯1号的花色苷积累首先出现于胚上方的花柱遗迹附近外,其余品种色素均首先在籽粒顶端出现,随后向四周延伸。玉米籽粒色素(除紫糯香)吸收峰随时间的变化先升高后降低。灌浆前期玉米果穗色素含量上部〉中部 〉下部,到灌浆后期,中部色素含量大于其他两部分色素含量。
Colourful maize (Zea mays L.) kernel contains a huge amount of pigments such as carotenoids and anthocyanins, which is the main origin of natural pigments. Many studies focused on the extraction method and pigments characteristics, but the accumulation regulations of maize pigments have not been clear yet. Four maize varieties with different colours such as Zinuoxiang (purple), Xixingchinuo 1 (red), Xixingheinuo 1 (black), and Tebao 2 (yellow) were used to study the composition, distribution and accumulation regularity of maize pigments by bare-handed sections and spectrophotometry. The results showed that the pigments of Xixingchinuo 1 consisted of carotenoids and anthocyanins. The anthocyanins mainly existed in seed capsule, which appeared firstly at the top of embryo nearby the style vestige, and then extended around. The dorsum of maize kernels contained higher anthocyanins contents than the abdomen. The carotenoids mainly existed in embryo and endosperm, which first appeared at the top of kernels, and then extended around with the time. Carotenoids were the predominant pigments in Tebao 2, and their distribution and accumulation regularities were consistent with those in Xixingchinuo 1. The pigments of Zinuoxiang and Xixingheinuo 1 were mainly anthocyanins, which predominantly existed in aleurone layer of maize kernels. The anthocyanins appeared at the top of kernels firstly, the absorption peak of pigments of maize kernels (except in Zinuoxiang) decreased after an initial increase with the grain-filling time. At the early stage of grain-filling, the pigment contents of maize kernels in the different parts of maize spike showed the following regulations: the upper 〉 the middle 〉 the basal. While at the late stage of grain-filling, the pigments contents of middle part of kernels of maize spike were much higher than those of other two parts.