杜仲形成层活动周期及过氧化物酶和酯酶同工酶的变化  

Periodicity of Cambial Activity and Variability of Peroxidase and Esterase Isozymes in Eucommia ulmoides Oliv

作　　者：罗立新[1] 崔克明[1] 李正理[1] 李举怀[2] 

机构地区：[1]北京大学生命科学学院 [2]北京农林科学院作物研究所

出　　处：《北京大学学报（自然科学版）》1999年第2期209-216,共8页Acta Scientiarum Naturalium Universitatis Pekinensis

基　　金：高等学校博士学科点专项科研基金;国家自然科学基金

摘　　要：杜仲（ＥｕｃｏｍｍｉａｕｌｍｏｉｄｅｓＯｌｉｖ．）形成层３月中旬恢复活动，７月下旬形成层细胞停止分裂，同时停止产生新的韧皮部细胞，但直到８月中旬才停止产生新的木质部细胞。１２月新形成的未成熟韧皮部和木质部细胞都继续分化、成熟。形成层活动周期中，过氧化物酶同工酶的酶谱和酶活性在形成层区域和木质部区域中变化最大。ＰＯⅠ和ＰＯⅡ组同工酶只在春季形成层恢复活动时期存在。ＰＯⅢ的酶活性在夏季减弱，而冬季达到最高水平。酯酶同工酶的酶谱和酶活性亦随形成层的活动状态发生变化。负极端的ＥＳＴⅢ～Ⅴ组酯酶同工酶在生长季节消失，当形成层休眠时又重出现。ＥＳＴⅡ的酶活性最强并在各个时期均存在，它在维管组织的发育分化中可能起重要作用。The cambium of Eucommia ulmoides Oliv resumed its activities in mid March.It ceased to produce new phoem cells at the end of July,but continued to differentiate into xylem cells until mid August,at which time the cambium became dormant albeit subsequent differentiation of newly formed immature phloem and xylem cells into mature ones continued until December.In consistent with the periodicity of cambial activity,the variability of peroxidase isozyme activity as demonstrated by isozymography was most significant in the cambial region.POⅠ and POⅡ presented only in the spring when cambium activity was resumed.The activity of POⅢ was weakened in summer and increased gradually reaching to the highest level in winter.The variability of esterase isozyme activity in the vascular tissues was in consistent with the periodicity of cambial activity.Isozyme bands of ESTⅢ￣Ⅴ near the negative pole of the zymograph disappeared in specimens collected during growth season and its activity was revived when cambium became dormant.Isozymes of ESTⅡ being the most active and present over time,might play an important role in devolopment and differentiation of vascular tissuess.

关 键 词：杜仲 形成层活动周期 过氧化物 同工酶 

分 类 号：Q949.751.5[生物学—植物学]