ABSTRACT The effects of elevated aluminium (Al) concentrations on parameters indicating Al toxicity and Al detoxification were evaluated in two alfalfa populations from different acidic soil environment. Plants were grown in nutrient solutions at pH 4.5, 5.5 and 6.0, with different levels of Al contamination for 30 days. Shoot heights and root activity were significantly decreased in the Al treatment while free proline concentration was significantly increased. Furthermore, citric acid and oxalic acid concentrations tend to increase with increasing Al concentration. Different responses were also observed between the two populations. Shoot height, free proline concentration and root activity were significantly higher for alfalfa plants collected from an acidic soil environment. These plants also exhibited higher concentrations of citric and oxalic acids when exposed to 100 μM Al at pH 4.5. Overall, the results indicate that alfalfa plants grown on acidic soils might develop mechanisms to be less affected by high Al concentration.

中文翻译：

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铝对营养液中生长的苜蓿根系活性、有机酸和游离脯氨酸积累的影​​响

摘要 在来自不同酸性土壤环境的两个苜蓿种群中评估了升高的铝 (Al) 浓度对指示铝毒性和铝解毒参数的影响。植物在 pH 值为 4.5、5.5 和 6.0 的营养液中生长 30 天，在不同的铝污染水平下。在铝处理中地上部高度和根活动显着降低，而游离脯氨酸浓度显着增加。此外，柠檬酸和草酸的浓度往往随着铝浓度的增加而增加。在两个群体之间也观察到了不同的反应。从酸性土壤环境中采集的苜蓿植株的枝条高度、游离脯氨酸浓度和根系活性显着更高。当暴露于 pH 4.5 的 100 μM Al 时，这些植物还表现出更高浓度的柠檬酸和草酸。总体而言，结果表明，在酸性土壤上生长的苜蓿植物可能会发展出受高铝浓度影响较小的机制。