鋅對阿拉伯芥生長的影響在根部長度方面最為顯著。阿拉伯芥在含有鋅的培養基處理期間，過氧化氫及過氧化酶隨著時間及鋅的處理濃度增加而升高。阿拉伯芥根部木質素的含量在鋅處理下也有升高的現象。阿拉伯芥可以耐受在含有高濃度的鋅( 4 mM )處理條件下生長，可能是因為鋅處理的阿拉伯芥組織所蓄積的高濃度過氧化氫，有部份被過氧化酶降解用於合成木質素。

The adverse effect of Zn on growth is apparent from the reduction in root length of the Zn-treated Arabidopsis roots. The levels of H2O2 were increased rapidly in Zn-treated Arabidopsis roots. The lignin biosynthesis realated enzymes, peroxidases and laccases were enhanced during the Zn treatments. The lignin contents increased in Zn-treated Arabidopsis roots. Arabidopsis can be tolerant to high concentration of Zn (4 mM), because part of high levels of H2O2 accumulated in Zn-treated tissues are utilized by peroxidases to synthesize the lignin.

TABLE OF CONTENTS
Chinese abstract ----------------------------------- I

English abstract ----------------------------------- II

Table of contents ---------------------------------- III

List of tables and figures ------------------------- IV

Introduction ---------------------------------------- 1

Materials and Methods ------------------------------- 6

Results --------------------------------------------- 13

Discussion ------------------------------------------ 17

References ------------------------------------------ 22

Tables and figures ---------------------------------- 27

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