在我們的研究中，在大豆( Glycine Max )下胚軸受傷組織其過氧化氫量的減少伴隨著過氧化酵素活性的增加。過氧化酵素活性在受傷處理後0.5天時有明顯的增加；而laccase活性則在受傷處理後1至2天時才有明顯的增加；由機械性傷害處理的過氧化酵素活性較laccase早發生。在受傷處理組織中，過氧化酵素和laccase活性的增加與木質素含量的上升有相關。我們推測在對照組的組織中，laccase或許在木質素合成的途徑中扮演主要的作用；因此，在傷害的過程中，過氧化酵素藉著利用過氧化氫在木質素合成的途徑中扮演主要的角色。

In our study, the decrease of H2O2 levels in wounding-treated tissues of soybean ( Glycine Max ) hypocotyls is accompanied by the enhancement of the POD activity. The POD activity was significantly enhanced 0.5 d after wounding treatment. The laccase activity was significantly enhanced 1-2 d after wounding treatment. The enhancement of POD by mechanical wounding occurred a day earlier than laccase. The increase in activities of POD and laccase is correlated with a rise in lignin contents in wounding-treated tissues. We suggest that in control tissues, laccase might play major role on the lignin biosynthesis, hence, POD by utilizing H2O2 play the major role on the lignin biosynthesis during the wounding process.

Abstract in Chinese 2
Abstract in English 3
Table of contents 4
List of tables and figures 5
Introduction 7
Materials and Methods 11
Results 18
Discussion 21
References 23
Tables and figures 28



List of Tables and Figures

Figure 1. Effect of mechanical wounding on the accumulation of H2O2 in soybean hypocotyls. 28

Figure 2. Effect of mechanical wounding on the peroxidase isozymes during the course of treatment in soybean hypocotyls. 29

Figure 3. Effect of mechanical wounding on the activities of the peroxidase isozymes in the soybean hypocotyls. 30

Figure 4. Quatification of peroxidase activity in soybean hypocotyls of mechanical wounding and control tissue. 31

Figure 5. Effect of mechanical wounding on the laccase isozymes in soybean hypocotyls. 32

Figure 6. Effect of mechanical wounding on the activities of the laccase isozymes in the soybean hypocotyls. 33

Figure 7. Quatification of laccase activity in soybean hypocotyls of mechanical wounding and control tissue. 34

Figure 8. Effect of mechanical wounding on the lignin content during the course of treatment in soybean hypocotyls. 35

Figure 9. Effect of mechanical wounding on transcripts accumulation of POD isozymes. 36

Figure 10. Quatification of on transcripts accumulation of POD isozymes of mechanical wounding and control tissue. 37

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