黑果腺肋花楸枝条的深超冷与抗寒性

差热分析法测得黑果腺肋花楸枝条有深超冷。黑果腺肋花楸低温放热峰的起始温度和组织褐变法测得的致死温度相吻合。以黑果腺肋花楸低温放热峰的起始温度作为枝条的抗寒性指标，抗寒性的季节变化表现为：晚秋至１２月上旬为抗寒性驯化阶段，１２月上旬至次年２月上旬为最强抗寒性维持阶段，２月上旬以后开始脱锻炼。初冬后的锻炼过程和早春的脱锻炼过程十分迅速并与环境温度密切相关。

Deep supercooling and cold hardiness of chokeberry shoots

Deep supercooling was found by Differential Termal Analysis(DTA)in xylem of chokeberry(Aronia melanocarpa Michx Ell.)shoots,The initiation temperature of low Temperature Exotherm(LTE)was coincided with the killing temperature determined by survival test. Seasonal changes in cold hardiness of chokeberry shoots expressed by initiation temperature of LTE showed that the acclimation period took place from autumn to early December. The chokeberry shoots maintained the highest cold hardiness from the early December of 1992 to the beginning of February of 1993.Shoots started their dcacclimation from carly February.The acclimation in late autumn and deacclimation in early-spring were sharp and temperature dependent.