铝胁迫对花生根系生长和生理特性的影响

摘要

In order to clarify the response of the peanut root to aluminum toxicity in acidic soil,the root growth and physiological characteristics of peanut (Arachis hypogaea L.)seedlings under different concentrations of aluminum were studied in this paper by hydroponics culture.The results showed that the growth of peanut seedling roots under the low concentrations of aluminum(0.5-1.0 mmol/L)was promoted at first nine days after aluminum treatment,the root length in 0.5,1.0 mmol/L aluminum treatment was improved by 9.6% and 16.6% respectively compared with CK,the root fresh weight in 0.5 ,1.0 mmol/L aluminum treatment was increased by 2.5% and 8.2% respectively compared with CK.The growth of peanut root in high concentrations of aluminum(≥2.0 mmol/L)was significantly inhibited.The root length and the root fresh weight in 8.0 mmol/L aluminum treatment were reduced by 45.0% and 26.5%respectively compared with CK at the first nine days after aluminum treatment.The SOD,POD activities of root in low concentrations of aluminum(0.5-1.0 mmol/L)were enhanced,and the root cell membrane permeability decreased,so the growth of peanut root was promoted.However, the SOD,POD activities of root in high concentrations of aluminum(≥2.0 mmol/L)decreased, and the root cell membrane permeability increased,so the growth of peanut root was inhibited.%为明确花生（Arachis hypogaea L．）根系对酸性土铝毒的反应，采用水培法研究了不同浓度铝条件下花生幼苗根系生长和生理特性的变化。结果表明：低浓度铝（0.5～1.0 mmol/L）可促进花生幼苗根系生长，至铝胁迫处理第9天，0.5、1.0 mmol/L铝胁迫处理根系长度分别较 CK（不添加铝）提高了9.6％、16.6％，根系鲜质量分别较 CK 提高了2.5％、8.2％；而高浓度铝（≥2.0 mmol/L）明显抑制花生根系的生长，至铝胁迫处理第9天，8.0 mmol/L铝胁迫处理根系长度、根系鲜质量分别较CK降低45.0％、26.5％。低浓度铝（0.5～1.0 mmol/L）可增强根系 SOD、POD活性，降低根系细胞质膜透性，对花生生长有一定的促进作用；高浓度铝（≥2.0 mmol/L）降低了根系SOD、POD活性，增大了根系细胞质膜透性，抑制花生根系的生长发育。