毛竹竹秆基本组织发育过程中过氧化物酶的超微定位

Ultracytochemical Localization of Peroxidase during the Ground Tissue Development in Phyllostachys edulis (Poaceae) Culms

利用电镜细胞化学技术对毛竹竹秆基本组织发育过程中过氧化物酶进行了细胞化学定位。基本组织细胞过氧化物酶活性由胞间隙处的胞间层开始逐渐向中间推进,同期过氧化物酶体、内质网等细胞器也具有酶活性,随后质膜和液泡膜出现酶反应物。次生壁形成期长细胞壁上过氧化物酶高活性主要集中在次生壁窄层中,以休眠期酶活性最高。随着年龄的增加,长细胞的过氧化物酶活性逐渐降低,九年生长、短细胞的过氧化物酶活性已很弱。短细胞的酶活性始终高于长细胞,细胞壁、质膜、运输小泡膜和纹孔也都具有较高的酶活性。短细胞伸长停止与高过氧化物酶活性有关。过氧化物酶分布和活性并不完全对应于木质素的沉积部位,短细胞的过氧化物酶可能参与了长细胞壁中木质素的合成。

The Ultracytochemical localization of peroxidase during the ground tissue development in bamboo Phyllostachys edulis culm was studied with cytochemical technology.In the primary wall development period,peroxidase concentrated in the intercellular layer near the intercellular space,and then extended to all intercellular layer,and at the same time the peroxisome,endoplasmic reticulum and mitochondria also showed peroxidase activity.After that the distribution of peroxidase appeared in the tonoplast and plasma membrane.In the secondary wall development period,peroxidase activity partially increased in the long cell walls and concentrated in the narrow lamellae,especially in dormancy period.The peroxidase activity in the narrow lamellae of the long cell walls declined gradually with aging,and in nine years old culm there was little peroxidase reactive product both in the long and short cells.The short cell always had higher peroxidase activity than that of the long cell.The cell wall,plasma membrane,transfer vesicles and pits of the short cell had also shown higher peroxidase activity.A relationship between peroxidase and the differentiation of the ground tissue in bamboo culms was also discussed.