Abstract: Abstract：【Objective】To study the law of changes about sucrose content ratio and sucrose-metabolizing enzymes specific activities in the florescence of peach.【Method】The content of sucrose, starch and the specific activities of sucrose-metabolizing enzymes, including acid invertase(AI), neutral invertase(NI), sucrose phosphate synthase(SPS) and sucrose synthase (SS) were studied in florescence（from the period of bud to wilt）of JingYu and Kubao peach.【Result】The rule of sucrose accumulation took a similar change in disparate parts of two varieties, and the content ratio was obviously higher in phloem than other parts. The content of soluble total sugar assumed descendent trend in the mass, and the content in phloem was higher than it in other parts except for the individual value in petal on the day of full flower (the 10th). At the same time the content of starch was elevatory continuously in ovary and leaf during florescence, and it reduced in phloem besides the content depressed then elevatory in petal. The specific activity of AI and NI kept infirm influence to the increase of sugar content, whereas sucrose accumulation accorded with SS-synthese and SPS specific activity. The accumulation and components of sugar were affected evidently by SS-disassemble activity.【Conclusion】Phloem was the fountainhead of carbohydrate-metabolizing in the florescence of peach. The space-time character expression of sucrose-metabolizing enzymes were regulated by correlative factors.

Key words: Peach, Florescence, Sucrose, Enzyme