摘要
从 1 0个大豆品种中筛选出两个耐铝性差异显著的品种 ,研究了其耐铝性与有机酸的关系。经铝处理后 ,吴川品种的相对根长为 1 3 3 .5 % ,化州只有 68.9% ,表明吴川相对耐铝 ,化州对铝较敏感。将不同浓度的AlCl3 加入营养液中处理大豆 1 0d,化州较吴川根长受到较大影响 ,进一步证实吴川相对耐铝毒 ,而化州对酸铝敏感。机理研究发现大豆在铝胁迫下根系可分泌两种有机酸 (草酸、柠檬酸 ) ,其中吴川根系草酸分泌速率提高了 74% ,化州几乎没有提高 ,表明耐铝性大豆品种的根系草酸分泌速率明显提高 ,可增强其缓解酸铝毒性的能力。而二者分泌柠檬酸的速率虽然均有显著提高 ,但处理后感抗品种之间差异不大 ,表明柠檬酸在缓解铝毒性中的作用不大。铝处理下大豆根系虽然分泌两种有机酸 ,但草酸在大豆耐酸铝机制中的作用可能更为重要。
Two soybean cultivars WUCHUAN,HUAZHOU differing in Al tolerance were screened from 10 soybean cultivars and used to study Al tolerance mechanisms. The results showed that the relative roots length of the Al-resistant cultivars WUCHUAN was 133.5 % while the Al-sensitive cultivars HUAZHOU was 68.9%. The resistance of the selected cultivars was further confirmed by treating the plants for 10 d with different concentrations of AlCl 3 in culture solution. Tow organic acids were induced to exude by Al toxicity from soybean roots. Oxalate exuded rate of WUCHUAN was increased by 74% in response to Al toxicity,while HUAZHOU had no significant change. It meant the possibility of oxalate detoxifying of the aluminum toxicity in the Al-tolerant soybean cultivars was enhanced. The rate of citrate exuded in the two soybean cultivars both increased in response to Al toxicity stress but no significant difference between them was observed. These results suggested that oxalate might play more important role in the Al tolerance mechanism of soybean than citrate.
出处
《广西植物》
CAS
CSCD
北大核心
2004年第6期554-557,549,共5页
Guihaia
