銅處理花生根部組織會抑制根的生長、內生的indole-3-acetic acid（IAA）含量減少、cationic peroxidese活性增加和cationic peroxidese（pI 8.5）transcript增加。所以我們推測銅處理誘導cationic peroxidese合成進而分解內生的IAA抑制根的生長。另外，anionic peroxidase（pI 3.5）活性和lignin含量也有增加，所以我們推測銅誘導花生根部組織內anionic peroxidase催化monolignols聚合成lignin，且反應中移除了多餘的hydrogen peroxide亦有detoxifying的作用。

Cu-treated peanut seedlings not only showed a significant inhibition in peanut root growth, but also a decrease in endogenous indole-3-acetic acid (IAA) contents . The decline of IAA content in Cu-treated tissues is accompanied by an increase in cationic peroxidase activity. In addition, the increase in cationic peroxidase (pI 8.5) activity is correlated with an increase in cationic peroxidase transcripts. Cu might suppress the growth of peanut roots by inducing the synthesis of the cationic peroxidase isozyme that degrades endogenous IAA, causing the retardation of peanut root growth. The increase in activity of anionic peroxidases (pI 3.5) is also correlated with the rise in lignin content in Cu-treated roots. We suggest that the increase in anionic peroxidases (pI 3.5) induced by Cu might be responsible for lignin synthesis in peanut roots, and remove excess hydrogen peroxide, thus serving a detoxifying role during Cu treatment.

TABLE OF CONTENTS

Chinese abstract ----------------------------- I

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

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

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

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

Materials and Methods ------------------------- 3

Results --------------------------------------- 9

Discussion ----------------------------------- 12

References ----------------------------------- 14

Tables and figures --------------------------- 18

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