中文摘要：

采用室内砂培方法,对3个大豆品种的根系分泌物进行了收集、浓缩,对比其有机酸和酚酸物质种类和数量的差异。结果表明,感病大豆品种合丰25号根系分泌物中的主要有机酸种类丰富,含量高;抗病品种绥农10号和抗线2号根系分泌物中主要有机酸种类单一,含量低。随着生育期的变化,感病品种合丰25号的有机酸总量在花期达到最高,以后逐渐下降;绥农10号的有机酸变化趋势与之相似;抗线2号在花期达到最高,苗期最低。感病大豆品种合丰25号在苗期根系分泌物中发现对羟基苯甲酸和香草酸两种酚酸,对羟基苯甲酸含量在鼓粒期最高,其次是苗期和花期,成熟期最低。两个抗病大豆品种成熟期前的根系分泌物中仅检测到对羟基苯甲酸,其含量以花期或鼓粒期最高,苗期和成熟期最低。

英文摘要：

Root exudates of three soybean cultivars were collected and concentrated under sand culture. The species and amount differences of organic acids and phenolic acids were compared. Result showed that the species and amount of organic acids in root exudates from susceptible cultivar Hefeng 25 （H25） were more and higher, while those from resistant cultivars Suinong10 （S10） and Kangxian2 （K2） were single and low. With the changes of growth stage, total organic acids in susceptible cultivar H25 reached peak value at flowering stage and then decreased. So did S10. But the total content of organic acids in root exudates from K2 at seed -filling stage was the highest. Two phenolic acids, which were p - hydrobenzoie acid and vanillic acid, were detected in root exudates from H25 in seedling stage, p-hydrobenzoic acid reached peak value at seed- filling stage, following with seedling stage and flowering stage with maturing stage the lowest value. Only p -hydrobenzoic acid was found in root exudates from the two resistant cultivars. Its content reached peak value at flowering stage at seed-filling stage, while that and seedling stage and maturing stage were the lowest.