外源5-氨基乙酰丙酸对红香芋试管苗耐冷性的影响

Effect of Exogenous 5-aminolevulinic Acid on Cold Tolerance of Taro Plantlets in vitro

为探讨外源5-氨基乙酰丙酸对芋试管苗耐冷性的影响,以红香芋为试材,通过人工模拟低温逆境,研究了不同浓度外源ALA处理下芋试管苗耐冷性相关生理指标的变化。结果表明:短期(16 h)低温胁迫下,添加2～20 mg/L外源ALA可减轻芋试管苗冷害程度,提高超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性,降低超氧阴离子(.O2-)产生速率和过氧化氢(H2O2)含量,抑制丙二醛(MDA)含量和质膜透性的上升,同时增强细胞渗透调节能力。以上结果说明,适宜浓度的ALA处理可缓解低温胁迫对芋试管苗的伤害,提高其耐冷性;ALA处理浓度以10 mg/L效果最好。

The effects of different concentrations of exogenous 5-aminolevulinic acid（ALA） on the cold tolerance and related physiological indexes of taro [Colocasia esculenta（L.） Schott] plantlets in vitro were studied under the low temperature stress simulated artificially.The results showed that： under short-term（16 h） low temperature stress,the 2~20 mg/L exogenous ALA treatment could reduce the damaged degree of taro plantlets in vitro,promote the activities of superoxide dismutase（SOD）,peroxidase（POD）,catalase（CAT） and ascorbic acid peroxidase（APX）,decrease the production speed of superoxide anion（·O2-） and the content of hydrogen peroxide（H2O2）,suppress the increase in malonaldehyde（MDA） content and plasma membrane permeability,and strengthen the ability of cell osmoregulation.The above results indicated that the ALA with suitable concentration could enhance the cold tolerance of taro plantlets in vitro,and relieve the injury of low temperature stress to taro test-tube plantlets.The application of 10 mg/L ALA could obtain the best effect.