杨树叶片酚类物质对秋季温度骤降的响应

Responses of Phenolic Compounds in Poplar Leaves to Abrupt Temperature Decrease in Autumn

秋季,在黑林五号杨、黑林三号杨和中绥杨尚未进入休眠期时对其进行了温度骤降处理,观测温度骤降对黑林五号杨、黑林三号杨和中绥杨叶片的膜透性以及叶片中酚类物质含量、多酚氧化酶活性的影响。结果表明:A5叶片细胞膜对低温伤害的自我保护功能最强,A43次之,中绥最弱。此外,抗冻性较弱的中绥叶片中总酚、木质素、缩合单宁含量较低,而多酚氧化酶活性较高。3种杨树叶片中总酚、黄酮、木质素的含量在温度骤降时均无显著变化,叶片中缩合单宁含量和多酚氧化酶活性变化因杨树的抗冻性而不同。

An experiment was conducted to study the responses of membrane permeability, phenol content and polyphenol oxidase activity of leaves to an abrupt temperature decrease in autumn using poplar Populus psuedo-simonii ×P. nigra ×P. nigra CL. ‘AS＇ , P. psuedo-simonii ×P. nigra ×P. nigra CL. ‘Heilin Ⅲ ＇ and P. deltoides × P. cathangana as testing materials. Results show that the cell membrane of P. psuedo-simonii ×P. nigra ×P. nigra CL. ‘AS＇ leaves has the highest cold resistance, and then followed by P. psuedo-simonii ×P. nigra ×P. nigra CL. ‘Heilin Ⅲ＇ and P. deltoides ×P. cathangana. The contents of total phenol, lignin and condensed tannin in P. deltoides ×P. cathangana leaves are lower, but the polyphenol oxidase activity is higher. There is no significant change in total phenol, lignin, flavonoid in leaves of these three poplar varieties after the abrupt temperature drop. The content of condensed tannin and the polyphenol oxidase activity in leaves change with cold resistance of different poplar varieties.