Abstract: 【Objective】 The objective of this study is to elucidate the relationship between changes of physiological indexes in different fruit tree leaves of jujube, peach, cherry and grape and preference degree of Apolygus lucorum, and to analyze the physiological defense mechanism of damaged leaves by A. lucorum, providing a scientific basis for effective control of the pest. 【Method】The damage indexes of different fruit trees were investigated in the orchard, and biochemical analyses were conducted to study changes of various physiological indices in damaged leaves of different fruit trees. 【Result】Soluble sugar contents increased in four fruit tree leaves except peach leaves after damaged by A. lucorum, and increased up to 87.83% in jujube leaves. The content of protein decreased in four fruit trees leaves, and no significant difference in protein was found between pierced and contrast leaves except peach leaves. Free amino acid contents increased in four fruit tree leaves, with the increase rate having a positive correlation with damage index, contrast to the piercing of A. lucorum. The POD activities in four fruit tree leaves showed an increasing trend, and increased by 112.92% in jujube leaves. The SOD activities increased in other tree leaves except cherry leaves, with a high increase rate of 40.95% in jujube leaves. No significant difference in CAT was found between pierced and contrast leaves of four fruit trees. 【Conclusion】After damaged by A. lucorum, the changes of physiological indexes in different kinds of leaves were different. The changes of soluble sugar, amino acid contents, POD and SOD activities showed a positive correlation with the preference of A. lucorum, while the protein contents and CAT activities showed no significant correlation with the preference of A. lucorum.

Key words: Apolygus lucorum, physiological indexes, jujube, peach, cherry, grape