9种青冈属植物抗寒性综合评价

Comprehensive Evaluation of Cold Resistance of Nine Cyclobalanopsis Species

为研究青冈属不同种之间抗寒性的差异,选择了9种青冈属植物5年生苗,对露地冻害情况进行调查,测定了一年生枝条在7个低温梯度下的各项生理指标,运用Logistic方程计算出半致死温度,利用相关性分析筛选出与抗寒性相关的关键指标,结合隶属函数法和聚类分析,对抗寒性进行综合评价。结果表明,小叶青冈、细叶青冈和青冈栎露地越冬表现较好,受冻害较轻。9个树种相对电导率变化均为“S”型曲线,半致死温度在-7.92~-15.12之间,其中小叶青冈半致死温度最低。可溶性糖、可溶性蛋白、游离脯氨酸、过氧化物酶和超氧化物歧化酶基本呈现先增后减的趋势,丙二醛呈现逐渐升高的趋势。不同树种同一温度下各指标含量差异显著。隶属函数法推断出抗寒性从强到弱依次为小叶青冈、细叶青冈、青冈栎、赤皮青冈、多脉青冈、褐叶青冈、毛果青冈、突脉青冈、滇青冈。聚类分析结果小叶青冈为第一类,抗寒性最强,细叶青冈、青冈栎、赤皮青冈、突脉青冈和褐叶青冈为第二类,抗寒性较强;毛果青冈为第三类,抗寒性中等;突脉青冈和滇青冈为第四类,抗寒性最弱,与露地表现基本一致。

In order to study the differences of cold resistance among Cyclobalanopsis species,9 species of Cyclobalanopsis were selected for 5 years to investigate the frost damage in the open field,and various physiological indexes of annual branches under 7 low temperature gradients were measured.The semilethal temperature was calculated by using Logistic equation,and the key indexes related to cold resistance were screened by using correlation analysis.Combined with the membership function method and cluster analysis,the cold resistance was comprehensively evaluated.The results showed that Cyclobalanopsis myrsinifolia,Cyclobalanopsis gracilis and Cyclobalanopsis glauca had better overwintering performance in the open field,and suffered less frost damage.The changes of relative conductivity of the 9 tree species were"S"curves,and the semi lethal temperature was between-7.92~-15.12,among which Cyclobalanopsis myrsinifolia has the lowest semi lethal temperature.Soluble sugar,soluble protein,free proline,peroxidase and superoxide dismutase basically increased first and then decreased,while malondialdehyde gradually increased.The content of each index of different tree species at the same temperature was significantly different.The subordination function method infered that the cold resistance from strong to weak was Cyclobalanopsis myrsinifolia,Cyclobalanopsis gracilis,Cyclobalanopsis glauca,Cyclobalanopsis gilva,Cyclobalanopsis myrsinifolia multinervis,Cyclobalanopsis stewardiana,Cyclobalanopsis pachyloma,Cyclobalanopsis elevaticostata and Cyclobalanopsis glaucoides.Cluster analysis results showed that Cyclobalanopsis myrsinifolia was the first type,with the strongest cold resistance.Cyclobalanopsis gracilis,Cyclobalanopsis glauca,Cyclobalanopsis gilva and Cyclobalanopsis myrsinifolia multinervis were the second type,with strong cold resistance.Cyclobalanopsis pachyloma was the third type,with moderate cold resistance.Cyclobalanopsis elevaticostata and Cyclobalanopsis glaucoides were the fourth type,with the weakest cold resistance,which was basically consistent with the performance in the open field.