荔枝花芽分化过程中多胺 、核酸和蛋白质的动态

Dynamic Changes in Polyamine, Nucleic Acid and Proteins During the Differentiation of Litchi (Litchi chinensis Sonn.) Floral Bud

荔枝茎尖由营养生长转变为生殖生长时，多胺含量达到高峰（115．79nmol g^-1，FW），该过程先于核酸和蛋白质的大量合成，表明多胺影响了DNA的复制、转录和翻译．成熟秋梢叶片不含腐胺（Putrescine，Put），但含亚精胺（Spermindine，Spd）和精胺（Spermine，Spm），其F／L的比值维持在1～3；叶片中可溶性蛋白的含量随顶芽或花（序）芽中含量的增加而增加，其相关系数R=0．9294，表明叶片含氮化合物的代谢对荔枝茎尖由营养生长转变为生殖生长及其发育过程极为重要．

The content of polyamine increased to a peak level between leaf bud stage and primary panicle development of litchi, which occurred earlier than the mass-synthesis of nucleic acid and proteins. Therefore, polyamine might affect floral development by regulating the synthesis of biological macromolecule. The contents of Spm, Spd and soluble proteins in the mature top leaf increased along with the increasing of Spm, Spd and soluble proteins in terminal buds or floral buds. It showed that the metabolism of nitrogenous compounds in leaf was vital for stem apex shifting from nutritive growth to reproductive growth. Thus, this article offers theoretic basis for using nitrogenous fertilizer or urea to facilitate the differentiation of litchi floral buds.