Submitted to: Abstract of International Horticultural Congress
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2002
Publication Date: 6/21/2002
Citation: WANG, Y., WISNIEWSKI, M.E., MEILAN, R., WEBB, R., FUCHIGAMI, L. IMPROVED TOLERANCE TO ENVIRONMENTALLY INDUCED OXIDATIVE STRESSES IN TRANSGENIC TOMATO OVEREXPRESSING ASCORBATE PEROXIDASE. ABSTRACT OF INTERNATIONAL HORTICULTURAL CONGRESS. 2002. Interpretive Summary:
Technical Abstract: We studied the effect on oxidative stress resistance of overexpressing, in transgenic tomato (Lycopersicon esculentum) plants, a cytosolic ascorbate peroxidase (APX) gene derived from pea (Pisum sativum). Transformants were selected using Kanamycin resistance and confirmed by PCR, Southern and Northern analysis. Several independently-transformed lines were obtained and evaluated for resistance to oxidative stresses resulting from exposure to salinity and high-temperatue. APX enzyme activity in leaves of the transgenic plants was several-fold greater than that of the wild-type (WT) plants under non-stressed conditions. Several lines of transformants were more resistant to heat, salt, cold, and paraquat than the non-transformants. Additionally, seeds obtained from the transformed plants germinated at 9 degres C in the dark, in contrast to seeds from the WT plants which did not germinate under these conditions. Shoots of transformed lines grew in media containing 0.20 M NaCl and produced roots at 40 degrees C whereas the WT plants grew poorly in the salt medium and produced no roots at 50 degrees C. A full quantitative assessment of the resistance of the transformed lines of tomato to oxidative stress is in progress.