中文摘要
鋅處理大豆 (Glycine max) 幼苗會明顯抑制根的生長，增加PODs和laccases活性。PODs (pI 8.3, pI 7.7, pI 4.8, pI 4.4 and pI 3.7) 和laccases (pI 9.4, pI 8.3, pI 7.4, and pI 3.7) 活性的增加伴隨著鋅處理組織內木質素含量的增加。在我們的結果中，推測laccases作用在鋅處理的早期，而當處理時間延長，laccases和PODs則共同作用在木質素的合成上。

Abstract
The significant root growth inhibition in zinc-treated soybean (Glycine max) seedling correlated with the increase of PODs and laccases activity. The increase of the activities of PODs (pI 8.3, pI 7.7, pI 4.8, pI 4.4 and pI 3.7) and laccases (pI 9.4, pI 8.3, pI 7.4, and pI 3.7) are accompanied by a rise of lignin contents in Zn-treated tissues. Our results suggested that laccases work during the early stage of Zn treatment. Laccases and peroxidases work cooperatively in lignin synthesis when the time of Zn treatment was prolonged.

TABLE OF CONTENTS

Chinese abstract -------------------------------------------- 2
English abstract -------------------------------------------- 3

Table of contents ------------------------------------------- 4

List of tables and figures ---------------------------------- 5

Introduction ------------------------------------------------ 6

Materials and Methods --------------------------------------- 9

Results ---------------------------------------------------- 14

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

Reference -------------------------------------------------- 19
Tables and figures ----------------------------------------- 23

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