濒危树种越南青冈的半致死温度研究*

摘要

Cyclobalanopsis austrocochinchinensis is an endangered tree species of Fagaceae .The electrolyte leakage of leaf and stem from 2-year-old greenhouse container seedling of C.austrocochinchinensis were measured after 9 high and 8 low temperatures treatments .Logistic equation was fitted to calculate the lethal temperature ( LT50 ) . The results showed that electrolyte leakage was a sigmoid response curve to temperature , and fitted the Logistic e-quation very well .The high and low lethal temperature of leaf were 42.04℃and -1.78℃respectively; the high and low LT50 of stem were 46.62℃and -9.72℃respectively .These data are useful for predict the potential ge-ographical distribution of C.austrocochinchinensis, and provide basis for the cultivation , in-situ and ex-situ conser-vation of this endangered tree species .%越南青冈为壳斗科濒危树种。通过越南青冈2年生温室容器苗叶片和茎段分别在9个高温和8个低温温度处理后，测定其电解质渗出率，利用Logistic方程计算其高温、低温的半致死温度（ LT50）。结果表明，叶片和枝条组织的电解质渗出率与处理温度之间均呈“S”型曲线， Logistic方程拟合度较高；计算得到越南青冈2年生苗木叶片的高温、低温半致死温度分别为42.04℃和-1.78℃，茎段的高温、低温半致死温度分别为46.62℃和-9.72℃。研究结果可推测越南青冈的潜在地理分布区，为该濒危树种的人工栽培、就地或迁地保护提供依据。