Effects of bacterial shot-hole stress on proteins and amino acids contents in leaves of plum trees | 细菌性穿孔病危害对李树叶片蛋白质和氨基酸含量的影响

Chinese. 为判定细菌性穿孔病危害对李树叶片蛋白质和氨基酸含量变化的影响，以3个品种李树的病、健叶为试验材料，利用凯氏定氮仪及全自动氨基酸分析仪检测其蛋白质和氨基酸含量。结果显示，3个品种李树叶片受细菌性穿孔病危害后，蛋白质和氨基酸含量均出现了不同程度的下降，降幅与李树品种有关；细菌性穿孔病危害对李树不同病情等级叶片的蛋白质含量产生了极显著影响，各等级叶片的蛋白质含量出现变化，有升有降，但最终还是不能抵抗病害的胁迫，4级叶片的含量最低且显著区别于其他各级叶片；细菌性穿孔病危害对李树叶片的氨基酸种类无影响，均有必需氨基酸9种和非必需氨基酸8种，但绝大多数种类氨基酸含量通常随叶片病情等级的提高而呈现不同幅度的下降，只有极少数种类出现小幅度的提升，两者紧密关联。研究可为从生理生化角度探讨李细菌性穿孔病的致病机理提供基础数据。

English. To explore how leaves of plum trees are damaged by bacterial shot-hole stress, we collected the ailing and healthy leaves of three varieties of plum trees and investigated the contents of amino acids and proteins in these leaves by using Kjeldahl apparatus and automatic amino acid analyzer. The results showed that after infection of the bacterial shot-hole pathogen, the contents of amino acids and proteins in these leaves decreased in different degrees and these variations were associated with plum tree varieties. Protein contents of injure leaves with different disease levels showed great difference. All these leaves could not resist bacterial shot-hole stress, and protein contents in the leaves with the 4th disease grade was lowest than those in leaves with other disease grades. The kinds of amino acids in leaves of plum tree were not affected by bacterial shot-hole stress. There were 9 essential amino acids (EAAs) and 8 non-essential amino acids (NEAAs) in all tested leaves, but the contents of the majority of amino acids decreased at different extent with the increase of the disease grades, only the content of few kinds of amino acids increased slightly. This research provides basic data for further research on pathogenic mechanism of the bacterial shot-hole pathogen from the perspective of physiology and biochemistry.