低温胁迫下常春藤对外源脱落酸的生理响应

Physiological Response of Ivy to Exogenous Abscisic Acid Under Low Temperature Stress

以2个月、6个月和1年苗龄的中华常春藤为试材,分别用0、5、10mg·L^(-1)的脱落酸(ABA)溶液喷施各苗龄的常春藤,5℃低温胁迫12、36、72、144 h后测量常春藤的光合参数,并测定叶片中丙二醛、叶绿素、可溶性蛋白质、活性氧的含量和4种抗氧化酶活性等生理指标,探究外源ABA对低温下常春藤抗寒相关生理指标的影响,以期为增强常春藤抗寒性提供参考依据。结果表明:5 mg·L^(-1)ABA可以显著降低丙二醛和活性氧含量,增强了超氧化物歧化酶、过氧化物酶等抗氧化酶活性,提高了渗透调节物质可溶性蛋白质和游离脯氨酸含量;低温胁迫下1年苗龄的常春藤在ABA处理后各项生理指标变化最明显,表现出更强的抗寒性。喷施适宜浓度的ABA可以增强常春藤的抗寒性,缓解低温胁迫对常春藤的伤害,并且外源ABA对年龄越大的常春藤缓解效果越明显。

Two-month-old, six-month-old and one-year-old ivy were sprayed with 0 mg·L^(-1),5 mg·L^(-1) and 10 mg·L^(-1) abscisic acid solution(ABA) respectively.The photosynthetic parameters of ivy were measured after 12,36,72 hours and 144 hours of low temperature stress at 5 ℃,the contents of MDA,chlorophyll, soluble protein, reactive oxygen species and the activities of four antioxidant enzymes in leaves were measured for the last time, to explore the effect of exogenous ABA on cold resistanced related physiological indexes of ivy under low temperature, in order to provide a reference basis for enhancing the cold resistance of ivy.The results showed that 5 mg·L^(-1)ABA could significantly reduce the contents of MDA and reactive oxygen species, enhance the activities of antioxidant enzymes such as superoxide dismutase(SOD) and peroxidase(POD),and increased the contents of soluble protein and free proline.Under low temperature stress, the physiological indexes of one-year-old ivy changed most significantly after ABA treatment, showing stronger cold resistance.Spraying the appropriate concentration of ABA could enhance the cold resistance of ivy and alleviate the damage of low temperature stress to ivy, and the mitigation effect of exogenous ABA on the older ivy was more obvious.