Abstract:In order to investigate the characteristics of carbohydrate accumulation during the expansion stage of Colocasia esculenta (L.) Schott microcorm, with aseptic ‘Hongxiangyu’ plantlets as material, we studied the changes of the major carbohydrate content and the relevant enzymes activities as well as their correlation under high glucose concentration. The results showed that:(1) The contents of fructose, glucose and soluble sugar all increased firstly and then decreased during the development of microcorm. The fructose content of corms reached the maximum after 27 days induction, and the highest contents of total soluble sugar and glucose appeared on the 34th day. The sucrose content represented an updownup trend, peaking on the 48th day. (2) The contents of total starch, amylose and amylopectin increased with the incubation time. The total amount of starch reached the peak at late extension stage, accounting for about 76% of dry weight, and mainly was amylopectin. (3) Based on anatomical study, the starch granule density of storage tissue increased with the development of microcorm and covered the parenchyma cells in late stage. (4) Both of ADPGPase and Qenzyme activities reached the maximum on the 41st day, with 1.22 and 2.39 μmol·g-1·min-1,respectively. By correlation analysis between ADPGPase activity and total starch content, Qenzyme activity and amylopectin content, from shoots beginning to expand (20 d) to ADPGPase and Qenzyme activity reaching the peak (41 d), the correlation coefficient were 0.819 and 0.738, showing a significant positive correlation. The research suggested that the accumulation of starch and soluble sugar content changes were closely related to the development of ‘Hongxiangyu’ microcorm, and were regulated by related enzymes.