野生欧李果实中不同形态钙的含量及分布

以野生欧李为材料, 采用逐级提取的方法分析了果实中不同形态的钙在果实发育期含量变化及分布, 以期探明钙在欧李果实中含量变化和不同组织中的分布特性, 为揭示欧李高钙的机理提供材料。结果表明, 果实钙累积主要发生在两个阶段: 一是在幼果细胞分裂期, 即花后45 d出现一次累积高峰, 单果累积量达总量的69.39% , 另一次累积高峰发生在细胞膨大期, 累积时间持续30 d左右, 细胞分裂期以果胶钙形态积累为主, 而细胞膨大期以水溶钙形态积累为主; 果实各部位钙分布以果肉居多, 占单果钙累积总量的72.50% , 其次为核仁和核皮; 果实不同形态钙累积量为: 水溶钙>果胶钙>磷酸钙>草酸钙>残渣钙, 其中活性钙(水溶钙和果胶钙) 组分占钙累积总量的69.87%; 嫁接欧李果实中不同形态钙含量组成比例无明显改变。

Contents and Distribution of Different Forms of Calcium in Prunus humilis

In order to explore the characteristic of calcium content variation and distribution in different tissues,and the mechanism of higher calcium content in Chinese dwarf cherry(Prunus humilis) fruit,different kinds of calcium contents,which were extracted by sequential extraction procedure,were analyzed during the fruit development.The results showed that the accumulation of calcium in fruits appeared in two periods,one was the mitotic period of young fruits,which appeared in 45 d after flowering and the accumulation amount accounted for 69.39% of the single fruit calcium;the other appeared in the period of cell swelling and lasted for about 30 d,calcium pectate was the main form in the mitotic period,while the soluble calcium was the main form in the swelling period.The order of calcium contents in different parts of P.humilis fruits was as follows:pulp>pit kernel>pit hull,which accounted for 72.50%,15.94% and 11.56% of the total calcium contents,respectively.The order of calcium forms accumulated in fruits was as follows:soluble calcium>calcium pectate>calcium phosphate>calcium oxalate>residual calcium,and active calcium(including soluble calcium and calcium pectate) accounted for 69.87% of the total calcium contents.It was concluded that active calcium was the main form of calcium absorption,transportation and accumulation,and it also became the main reason for the characterization of higher calcium contents in P.humilis fruit.The ratio of different kinds of calcium in grafting tree had no significant change.