中文摘要：

碳水化合物的种类和含量是决定果实品质的重要因素，果实中碳水化合物的转化、积累除受内源激素、韧皮部卸载等因子影响外，很大程度上依靠其代谢相关酶活性的调控。糖是植物生长、发育的一个重要的、多重的角色，是果实生长发育的基础物质，同时为果实细胞膨大提供渗透动力。山梨醇属于糖醇类，是山梨糖光合同化产物，可以作为可溶性贮存物质，也可作为类似于蔗糖的一种同化物运输物质。

英文摘要：

The sorbitol, fructose and glucose contents and the changes in activities of sorbitol oxidase （SOX）, sorbitol dehydrogenase （SDH）, which are the enzymes participated in sorbitol metabolism, were investigated respectively in the endocarp, mesocarp, leaf and phloem during the development of fruits of ＇Jingyu＇ and ＇Okubao＇ peach. The results demonstrated that the pattems of sugar accumulation were analogous in the two varieties. In addition, sorbitol content in leaf was the highest in leaf, followed by that in phloem, and then in pericarp. The contents of glucose and fructose had obvious diversity in disparate parts. At the same time, the changes of SDH and SOX activities had same trend in the two varieties, with a big wave in fruit, and relative unchanged over time in leaf and phloem. Moreover, the testing value of every index was close to zero in endocarp around the 60^th day or so after anthesis, which suggested that the basic metabolism was stagnated. However, the sorbitol metabolism in mesocarp increased sharply, which reflected it came into a new development stage.