Abstract:

This paper studied the resistance of four coloredleaf species in Prunus to sulfur dioxide to provide scientific references for selecting proper species as ornamental trees in landscape. The changes in activities of superoxide dismutase (SOD) and peroxidase (POD), membrane permeability, pH of extracted leaf fluid, and contents of malondialdehyde (MAD), proline and soluble proteins, absorbed sulfur were measured with two year old potted seedlings of Prunus cerasifera var. atropurpurea, Prunus×cistenena `Pissardii',
Prunus wrasifers `nigra' and Prunus×bliriana `Meirenmei' which were cultivated in a closed chamber after being treated with different concentrations of sulfur dioxide. The results showed that the membrane permeability, contents of MDA, proline, soluble protein, absorbed sulfur and the activities of SOD, POD, CAT increased, while the pH value decreased with the increment of sulfur dioxide concentration. The seven indexes, therefore, can be considered as main indexes for evaluating the resistance of colored\|leaf plants to SO<sub>2</sub> There was significant difference in absorbed sulfur content among four tree species, with the most in P. wrasifers `nigra'. Synthetical evaluation result of subordinate function analysis suggested that the resistance of four coloredleaf species to sulfur dioxide ranked from P. cerasiferavar. atropurpurea, P. wrasifers`nigra', P.×bliriana`Meirenmei' to P.×cistenena `Pissardii'.

Key words: Prunus, coloredleaf species, resistence to sulfur dioxide, membrane lipid peroxidation, activity of antioxidant enzymes, proline, soluble protein