Cold Tolerance of Illicium henryi Diels and Sarcococca hookeriana var.digyna Franch at Natural Low Temperature
Illicium henryi Diels and Sarcococca hookeriana var.digyna Franch were used as test materials,and the morphological changes of their leaves were continuously observed during the overwintering period.The physiological indexes related to cold tolerance,such as chlorophyll,relative conductivity and soluble sugar,were measured,in order to provide a practical basis for the introduction of the two plants or their conspecifics in most northern regions.The results showed that the two plants were able to maintain a better growth condition under the cold environment,with strong cold-tolerant ability.During the overwintering process,the relative conductivity and peroxidase activity of the leaves of the two plants first increased and then decreased.The soluble protein content first decreased and then increased,and the soluble sugar content increased with the decrease of the temperature.The correlation between each index and the air temperature was also larger.In conclusion,the two plants showed certain adaptive ability to the low temperature environment in the introduction site,and could operate various regulatory mechanisms to resist the low temperature damage in time.