The AQY of pear grafted on P. betulaefolia declined less than that on P. calleryana.
其中，以豆梨为砧的组合下降幅度大于以杜梨为砧的相同处理组合。
2
The essential oil from the flowers of Pyrus betulaefolia Bunge was abstracted by steam-stilling and analyzed by capillary GC-MS method.
采用水蒸气蒸馏法从杜梨花中提取挥发油，用气相色谱-质谱法对化学成分进行鉴定。
3
Microwave, water bath and ultrasonic extraction were employed to extract the polysaccharide from Pyrus Betulaefolia Bge. leaf and anthrone-sulphuric acid colorimetry was used to determine its content.