Effect of phosphorus deficiency on aluminium‐induced citrate exudation in soybean (Glycine max)
Effect of phosphorus deficiency on aluminium‐induced citrate exudation in soybean (Glycine max)
复制标题
DOI：
10.1034/j.1399-3054.2003.1170210.x
复制
发表时间：
2003-02
影响因子：
6.4
通讯作者：
H. Nian;Sung-ju Ahn;Zhen-ming Yang;H. Matsumoto
中科院分区：
文献类型：
--
作者：
H. Nian;Sung-ju Ahn;Zhen-ming Yang;H. Matsumoto
铝毒或缺磷可诱导植物根系分泌有机酸，这被认为是植物对铝毒或缺磷的一种耐受机制。以3个耐低磷性不同的大豆品种为材料，研究了缺磷对铝诱导的柠檬酸分泌的影响。单独磷饥饿不能诱导所有三个大豆品种的有机酸分泌。然而，磷缺乏改变铝诱导柠檬酸渗出随着时间的推移，表现出复杂的相互作用。短期磷饥饿（4天）使铝诱导的柠檬酸盐分泌增加50%，而长期磷饥饿（10天）使铝诱导的柠檬酸盐分泌减少到痕量。然而，在完全营养液中再恢复1天后，Al诱导的柠檬酸盐从恢复的根中的分泌比连续磷饥饿的植物高约6倍，但仍比磷充足的对照低约3.6倍。随着供磷或供铝量的增加，铝诱导的柠檬酸分泌量增加，而大豆根系铝积累量则随着供磷量的减少而减少。缺磷降低了叶片光合速率、气孔导度和蒸腾速率，增加了胞内CO2浓度。这些结果表明，磷营养对铝诱导的大豆根尖柠檬酸分泌和铝积累有显著影响。
Aluminium (Al) toxicity or phosphorus (P) deficiency can induce exudation of organic acids from the roots of some plants, which is believed to be a tolerance mechanism against Al toxicity or P deficiency. In the present study, the effect of P deficiency on Al-induced citrate exudation was investigated in three soybean varieties differing in low-P tolerance. P starvation alone failed to induce secretion of organic acids from all three soybean varieties. However, P deficiency altered Al-induced citrate exudation over time, showing a complex interaction. Short × term P starvation (4 days) produced up to 50% increase in Al-induced citrate secretion, while longer-term (10 days) starvation reduced Al-induced citrate secretion to trace amounts. However, after a further 1 day in complete nutrient solution for recovery, Al-induced citrate exudation from the recovered roots was approximately 6 times higher than that from the continuously P-starved plants, but still approximately 3.6 times lower than that from the P-sufficient control. With increasing P or Al supply, Al-induced citrate exudation increased, while Al accumulation in soybean roots decreased in parallel with the decrease of P supply. The photosynthetic rate, stomatal conductance and transpiration were decreased by P deficiency, whereas the intracellular CO 2 concentration was increased. These findings indicate that P nutrition has a significant effect on Al-induced citrate exudation and Al accumulation in soybean root apices.