To investigate the adaptability of tree species introduced from other area to low temperature environment in Lushan mountain, in contrast to the native Rhododendron fortune, six rare and evergreen tree species such as Parakmeria Latungensis, Manglietia insignis, Manglietia chingii, Michelia szechuanica, Michelia maudiae, and Magnolia grandiflora were targeted in the paper. These tree species have been introduced and cultivated in Lushan botanical garden many years ago. Living leaves were conducted and sampled with three replicates between different periods in winter from each tree species. The 4 important physiological and biochemical indices of the living leaves from 7 tree species were measured and the effect of low temperature on the physiological and biochemical processes in 7 tree species were discussed. The results showed that:1) the soluble sugar contents were increased first and then decreased conversely along with the temperature changes in winter among most tree species. Except for michelia maudiae, in which the soluble sugar contents were decreased by 7.54 percent from December in last year to January in this year, the soluble sugar contents in the other tree species were increased by from 11.56 to 34.49 percent. The soluble sugar contents in Parakmeria Latungensis and Magnolia grandiflora were increased continuously along with the temperature changes in winter. 2) Except for Manglietia chingii and Magnolia grandiflora, the malondialdehyde contents were increased continuously along with the temperature changes in winter. The rising range was relatively larger in Manglietia insignis, Michelia maudiae and Michelia szechuanica from December in last year to January in this year than the other tree species. The rising range was relatively larger in Magnolia grandiflora, Manglietia chingii, Michelia maudiae and Rhododendron fortunei from January to March in this year than the other tree species. 3) Increased continuously in Parakmeria latungensis and Michelia maudiae, the superoxide dismutase activities were decreased first and then increased similarly along with the temperature changes in winter among most tree species. Increased first and then decreased in Magnolia grandiflora, the peroxidase activities increased continuously along with the temperature changes in winter among most tree species. There was the largest variability and the highest contents in peroxidase activities in Parakmeria latungensis across these tree species. 4) The results of ANOVA showed that there were significant different in soluble sugar contents and peroxidase activities in living leaves between different temperature degrees and among these tree species. However, the malondialdehyde contents and superoxide dismutase activities in living leaves were significant different between the different temperature degrees, but there were no differences across these tree species. Compared with the other indices, the soluble sugar contents could objectively reflect the variation in physiological and biochemical processes resulted from temperature changes in winter. Thus, the soluble sugar contents would be accepted as one of indices in assessing the cold resistance for plants in the region. Because there are differences in mechanisms of adaptability to lower temperature stress among tree species, the indices in assessing the cold resistance for plants should be considered carefully and completely.%为了探讨引种的珍贵树种对庐山冬季低温环境的适应性，以庐山植物园引种栽培的6种常绿园林树种即乐东拟单性木兰（Parakmeria Latungensis）、红花木莲（Manglietia insignis）、桂南木莲（Manglietia chingii）、四川含笑（Michelia szechuanica）、深山含笑（Michelia maudiae）和广玉兰（Magnolia grandiflora）为研究对象，以庐山乡土树种云锦杜鹃（Rhododendron fortunei）为对照，采集冬季不同时期的鲜叶样品，分析了7个树种叶片4个主要生理生化指标随气温变化而变化的特征，研究低温环境对这些树种生理生化过程的影响。结果表明：1）在冬季，大部分树种的可溶性糖含量呈现出与气温变化相反的趋势即先上升后下降，只有深山含笑在1月份，比上年12月份下降了7.54%，其他树种增加幅度处于11.56%~34.49%之间，而乐东拟单性木兰和广玉兰的可溶性糖含量呈现不断上升趋势。2）除桂南木莲和广玉兰外，可反映植物耐寒程度的丙二醛含量呈现不断上升的趋势，从上年12月份到当年1月份，上升幅度较大的有红花木莲、深山含笑和四川含笑，而从1月份到3月份，增加幅度较大的为广玉兰、桂南木莲、深山含笑和云锦杜鹃等树种。3）乐东拟单性木兰和深山含笑呈逐渐增加的趋势，而大部分树种的SOD活性都呈现与气温相似的变化趋势即先下降后上升的趋势；除了广玉兰的POD活性先上升后下降，其他树种则不断上升，但不同树种POD活性大小及变化幅度不尽相同，POD活性最高且变异性最大的是乐东拟单性木兰。4）单因素方差分析表明，可溶性糖含量和POD活性在不同温度下和不同树种间存在显著差异，丙二醛含量和SOD活性只在不同温度下存在显著差异，树种之间差异不明显。通过分析4个表征植物耐寒性的生化指标，显示出可溶性糖含量能够较客观地反映植物随着气温变化所发生的生理生化变化，可作为本地区植物耐寒性的一个重要指标。由于不同树种适应低温环境的生理生化机制存在差异，在选择表征植物耐寒性的生化指标时，应综合分析。
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