铝诱导豇豆根系有机酸分泌特性的研究  

Study on organic acid secretion characteristics of cowpea root induced by Al

作　　者：于力[1,2] 孙锦[1] 郭世荣[1] 阎君[2] 朱为民[2] 

机构地区：[1]南京农业大学园艺学院,江苏南京210095 [2]上海市农业科学院园艺研究所/上海市设施园艺重点实验室,上海201106

出　　处：《南京农业大学学报》2013年第5期7-12,共6页Journal of Nanjing Agricultural University

基　　金：国家公益性行业(农业)科研专项(201003065);国家大宗蔬菜产业技术体系

摘　　要：以耐铝豇豆品种‘T6’和铝敏感豇豆品种‘S3’为试材,分析铝诱导根系有机酸的分泌特性,并以耐性品种‘T6’为试材,研究铝诱导的根系有机酸分泌与有机酸代谢的关系。结果表明:铝诱导豇豆根系分泌柠檬酸和苹果酸。苹果酸的分泌量随着铝处理浓度的增加而升高,耐铝品种苹果酸的分泌量高于铝敏感品种,‘T6’和‘S3’在50μmol·L-1铝处理时根系苹果酸分泌量分别是5μmol·L-1铝处理时的17.8和3.5倍。不同铝处理时间下2个豇豆品种根系有机酸的分泌均存在一个6 h的滞后期,属于分泌模式Ⅱ。随着铝处理浓度的增加,‘T6’根系苹果酸的分泌量显著增加,同时根尖苹果酸含量显著减少,与苹果酸代谢相关的酶活性没有显著变化;阴离子通道抑制剂蒽-9羧酸和蛋白合成抑制剂环已米特可以完全抑制铝诱导的豇豆根系有机酸分泌,根尖有机酸含量没有显著变化。推测:根系分泌苹果酸是豇豆抵御铝毒害的机制之一,苹果酸的分泌与苹果酸代谢无关,而阴离子通道可能介导此分泌过程。The organic acid secretion characteristics of cowpea （ Vigna unguiculata L. ） induced by A1 was studied by ＇ T6 ＇ （M-tolerant） and＇ S3 ＇ （Al-sensitive）. And the relationship between organic acid secretion of cowpea root induced by A1 and its metabolism was studied by＇ T6＇. The results were as follow： after exposure to A1, both citrate and malate were secreted from＇ T6＇ and ＇ S3＇ roots. The amount of malate secreted from＇ T6＇ roots was significantly higher than from＇ S3 ＇ and increased significantly by Al increase, and the secretion of malate from＇ S3＇ root did not significantly change with A1 increase. The amount of malate excreted from ＇ T6＇ and＇ S3＇ root after exposure to 50 μmol·L^-1 was 17.8 times and 3.5 times higher than 5 μmol·L^-1 , respectively. There was a 6 h lag-phase between organic acid excretion and A1 treatment, which suggested that this plant showed a pattern II -type. The malate secretion of＇T6＇tips increased and the malate content of＇T6＇ tips decreased by A1 increase, but there was no significant change in enzyme activity related to malate metabolism. The anion-channel inhibitor （Anthracene-9-carboxylicacid） and protein-synthesis inhibitor（Cicloheximide） completely inhibited the organic acid secretion of＇ T6＇root under A1 treatment, but the organic acid content did not change. So we presume that malate secretion was one of the A1 tolerance mechanism, the secretion of malate had no relationship with its metabolism, and anion channels might be involved in the secretion process.

关 键 词：豇豆 耐铝机制 有机酸 代谢酶活性 蛋白合成抑制剂 阴离子通道抑制剂 

分 类 号：S641.2[农业科学—蔬菜学]