以树莓（Rubus idaeus Linn.）品种‘Royalty’的当年生枝条（T1组）、冬季覆土厚度15 cm的二年生枝条（T2组）和冬季覆土厚度30 cm的二年生枝条（T3组）为研究对象，对6月和8月各处理组的二年生枝条木质部径向生长量、单小叶面积、小叶比叶质量、枝条水力结构（包括凌晨水势、正午水势、正午导水损失率和最大比导水率）、叶光合特性（包括净光合速率、气孔导度和水分利用效率）以及叶和枝条的非结构性碳含量（包括可溶性糖含量、淀粉含量和非结构性碳总含量）进行比较，并对不同处理组枝条的栓塞脆弱性曲线进行分析。结果表明：在6月和8月，T2组的二年生枝条木质部径向生长量显著（P＜0.05）低于T3组；3个处理组间的单小叶面积、正午水势、正午导水损失率、净光合速率和气孔导度差异显著，其中，正午导水损失率表现为T1组最低、T2组最高，其余指标表现为T1组最高、T2组最低；T2和T3组的凌晨水势、最大比导水率、可溶性糖含量、淀粉含量和非结构性碳总含量基本上低于或显著低于T1组，且T2组的上述指标低于T3组，而T2和T3组的小叶比叶质量和水分利用效率显著高于T1组。根据枝条栓塞脆弱性曲线，导水损失率为50%时，T1、T2和T3组的水势分别为-1.24、-0.73和-0.94 MPa，说明T1组的枝条栓塞脆弱性最小，T2组的枝条栓塞脆弱性最大。总体来看，在8月，各处理组的小叶比叶质量、正午导水损失率和水分利用效率低于6月，其余指标则高于6月。冬季覆土可明显降低树莓的低温冻害程度，且覆土厚度30 cm的效果优于覆土厚度15 cm。

 Taking annual branch （T1 group）， biennial branch with covering soil thickness of 15 cm in winter （T2 group）， and biennial branch with covering soil thickness of 30 cm in winter （T3 group） of cultivar ‘Royalty’ of Rubus idaeus Linn. as research objects， xylem radial increment of biennial branch， area of single leaflet， specific leaf mass of leaflet， hydraulic architecture （including predawn water potential， midday water potential， percentage loss of hydraulic conductivity at midday， and maximum specific hydraulic conductivity）， leaf photosynthetic characteristics （including net photosynthetic rate， stomatal conductance， and water use efficiency）， and non-structural carbon content in leaf and branch （including soluble sugar content， starch content， and total content of non-structural carbon） of each treatment group in June and August were compared， and vulnerability curves of branch embolism of different treatment groups were analyzed. The results show that in June and August， xylem radial increment of biennial branch of T2 group is significantly （P＜0.05） lower than that of T3 group； there are significant differences in area of single leaflet， midday water potential， percentage loss of hydraulic conductivity at midday， net photosynthetic rate， and stomatal conductance among three treatment groups， in which， percentage loss of hydraulic conductivity at midday of T1 group is the lowest， while that of T2 group is the highest， and other indexes of T1 group are the highest， while those of T2 group are the lowest； predawn water potential， maximum specific hydraulic conductivity， soluble sugar content， starch content， and total content of non-structural carbon of T2 and T3 groups are basically lower or significantly lower than those of T1 group， and above indexes of T2 group are lower than those of T3 group, while specific leaf mass of leaflet and water use efficiency of T2 and T3 groups are significantly higher than those of T1 group. According to vulnerability curve of branch embolism， when percentage loss of hydraulic conductivity is 50%， water potentials of T1， T2， and T3 groups are -1.24， -0.73， and -0.94 MPa， respectively， indicating that vulnerability of branch embolism of T1 group is the smallest， while that of T2 group is the largest. Overall， in August， specific leaf mass of leaflet， percentage loss of hydraulic conductivity at midday， and water use efficiency of each treatment group are lower than those in June， while other indexes are higher than those in June. Covering soil in winter can evidently decrease the degree of low temperature freezing injury of R. idaeus， and the effect of covering soil thickness of 30 cm is better than that of 15 cm.