銅處理大豆 ( Glycine max ) 根部組織會抑制根的生長，增加過氧化酶活性與組織內過氧化氫含量，推測銅引發過氧化酶活性的增加可能加強根部組織清除由銅引起之過氧化物的能力。另外，陽性過氧化酶（pI 8.9, pI 8.3, pI 7.7）及陰性過氧化酶（pI 6.5, pI 5.6, pI 4.4）的活性及木質素含量均有增加，所以推測銅誘導大豆根部組織內陽性及陰性過氧化酶催化木質素的合成。

Copper-treated soybean ( Glycine max ) seedling shows significant inhibition in soybean root growth, and enhancement in POD activity. Cu is an efficient catalyst in the formation of several reactive oxygen species and free radical. The increase in POD activity induced by Cu might remove excess hydrogen peroxide serving a detoxifying role during Cu-treatment. The increase of cationic ( pI 8.9, pI 8.3 and pI 7.7 ) PODs and anionic ( pI 6.5, pI 5.6 and pI 4.4 ) PODs activities is accompanied by a rise of lignin contents in Cu-treated tissues. We suggest that the increase in cationic ( pI 8.9, pI 8.3 and pI 7.7 ) and anionic ( pI 6.5, pI 5.6 and pI 4.4 ) PODs induced by Cu is responsible for lignin synthesis in soybean roots 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 --------------------------- 4
Results ---------------------------------------------- 10
Discussion ------------------------------------------ 14
Reference ------------------------------------------- 17
Figures ---------------------------------------------- 20

Baccouch, S., Chaoui, A. and Ferjani, E.E. (1998 ). Nickel-induced oxidative damage and antioxidant responses in Zea mays shoots. Plant Physiol. Biochem. 36, 689-694.
Beffa, R., Martin, H.V. and Pilet, P.E. ( 1990 ). In vitro oxidation of indoleacetic acid by soluble auxin-oxidase and peroxidases from maize root. Plant Physiol. 94, 485-491.
Bradely, D.J., Kjellbom, P. and Lamb, C.J. ( 1992 ). Elicitor- and wound- induced oxidative cross-linking of a proline-rich plant cell wall protein : a novel, radid defense response. Cell 70, 21-30.
Bruce, R. and West, C.A. ( 1989 ). Elicitation of lignin biosynthesis and isoperoxidase activity by pectic fragments in suspension cultures of castor bean. Plant Physiol. 91: 889-897
Cazalé, A.C., Rouet-Mayer, M.A., Barbier-Brygoo, H., Mathieu, Y. and Christiane, L. ( 1998 ). Oxidative burst and hypoosmotic stress in tobacco cell suspensions. Plant Physiol. 116, 659-669.
Chen, L.M. and Kao, C.H. ( 1999 ). Effect of excess copper on rice leaves : evidence for involvement of lipid peroxidation. Bot. Bull. Acad. Sin. 40, 283-287.
Cho, U.H. and Park, J.O. ( 2000 ). Mercury-induced oxidaative stress in tomato seedings. Plant Sci. 156, 1-9.
Christensen, J.H., Bauw, G., Welinder, K.G., Montagu, M.V. and Boerjan, W. ( 1998 ). Purification and characterization of peroxidases correlated with lignification in poplar xylem. Plant Physiol. 118, 125-135.
Gallego, S.M., Benavides, M.P. and Tomaro, M.L. (1996 ). Effect of heavey metal ion excess on sunflower leaces : evidence for involvment of oxidative stress. Plant Sci. 121, 151-159.
Gazaryan, I.G., Largimini, L.M., Ashby, G.A. and Thorneley, R.N.F. ( 1996 ). Mechanism of indole-3-acetic acid oxidation by plant peroxidase: anaerobic stopped-flow spectrophotometric studies on horseradish and tobacco peroxidases. Biochem. J. 313, 841-847.
Hammond-Kosack, K.E. and Jones, J.D.G. ( 1996 ). Resistance gene-dependent plant defense response. Plant Cell 8, 1773-1791.
Iiyama, K., Lam, TB-T. and Stone, B.A. ( 1994 ). Covalent cross-links in the cell wall. Plant Physiol. 104, 315-320.
Jana, S. and Choudhuri, M.A. ( 1982 ). Glycolate metabolism of three submerged aquatic angiosperms during aging. Aquat. Bot. 12, 345-354.
Klotz, K.L., Liu, T.T-Y., Liu, L. and Largimini, L. ( 1998 ). Expression of the tobacco anionic peroxidase gene is tissue-specific and development regulared. Plant Mol. Biol. 36, 509-520.
Lagrimini, L.M. ( 1991 ). Wound-induced deposition of polyphenols in transgenic plants overexpressing peroxidase. Plant Physiol. 96, 577-583.
Lagrimini, L.M. and Rothstein, S. ( 1987 ). Tissue specificity of tobacco peroxidase isozymes and their induction by wounding and tobacco mosaic virus infection. Plant Physiol. 84, 438-422.
Lagrimini, L.M., Bradford, S. and Rothstein, S. ( 1990 ). Peroxidase-induced wilting in transgenic tobacco plants. Plant cell 2, 7-18.
Lagrimini, L.M., Gingas, V., Finger, F., Rothstein, S. and Liu, T.T. ( 1997 ). Characterization of antisense transformed plants deficient in the tobacco anionic peroxidase. Pant Physiol. 114, 1187-1196.
Li, T.C., Feng, T.Y., Chen, W.S. and Liu, Z.H. ( 2001 ). The acute effect of copper on the levels of indole-3-acetic acid and lignin in peanut roots. Aust. J. Plant. Physiol. 28, 1-6.
Lin, C.C. and Kao, C.H. ( 2001 ). Abscisic acid induced changes in cell wall peroxidase activity and hydrogen peroxide level in roots of rice seedling. Plant Sci. 160, 323-329.
Liu, Z.H. and Ger, M.J. ( 1997 ). Changes of enzyme activity during pollen germination in maize and possible evidence of lignin synthesis. Aust. J. Plant Physiol. 21, 329-335.
Mäder, M. and Füssl, R. ( 1982 ). Role of peroxidase in lignification of tobacco cells: regulation by phenolic compounds. Plant Physiol. 70, 1132-1134.
Mazhoudi, S., Chaoui, A., Ghorbal, M.H. and Ferjani, E.E. ( 1997 ). Response of antioxidant enzymed to excess copper in tomato（Lycopersicon esculentum Mill）. Plant Sci. 127, 129-137.
Müsel, G., Schindler, T., Bergfeld, R., Ruel, K., Jacquet, G., Lapierre, G., Speth, V. and Schoptfer, P. ( 1997 ). Structure and distribution of lignin in primary and secondary cell walls of maize coleoptiles analyzed by chemical and immunological probes. Planta 201, 146-159.
Ouariti, O., Boussama, N., Zarrouk, M., Cherif, A. and Ghorbal, M.H. ( 1997 ). Cadmium- and copper-induced changes in tomato membrane lipids. Phytochemistry 45, 1343-1350.
Polle, A., Otter, T. and Seifert, T. ( 1994 ). Apoplastic peroxidase and lignification in needles of norway spruce ( picea abies L. ). Plant physiol. 106, 53-60.
Quiroga, M., Guerrero, C., Botella, M.A., Barceló, A., Amaya, I., Medina, M.I., Alonso, F.J., Forchetti, S.M., Tigier, H. and Valpuesta, V. ( 2000 ). A tomato peroxidase involved in the synthesis of lignin and suberin. Plant Physiol. 122, 1119-1127.
Richards, K.D., Schott, E.J., Sharma Y.K., Davis, K.R. and Gardner, R.C. ( 1998 ). Aluminum induces oxidative stress genes in Arabidopsis thaliana. Plant Physiol. 116, 409-418.
Sandmann, G. and Böger, P. ( 1980 ). Copper-mediated lipid peroxidation processes in photosynthetic membranes. Plant Physiol. 66, 797-800.
Teisseire, H. and Guy, V. ( 2000 ). Copper-induced changes in antioxidant enzymes actives in fronds of duckweed ( Lemna minor ). Plant Sci. 153, 65-72.
Wang, W.C. and Liu, Z.H. ( 1999 ). Harpinpss-induced peroxidase and lignin accumulation in tobacco during the hypersensitive response. Aust. J. Plant Physiol. 26, 265-272.
Weekx, J.E.J. and Clijsters, H.M.M. (1996 ). Oxidative damage and defense mechanism in primary leaves of Phaseolus vulgarus as a result of root assimilation of toxicity amounts of copper. Physiol. Plant. 96, 506-512.