中文摘要：

以3~4年生生长旺盛期柠条、沙柳、沙棘、白沙蒿为研究对象,供试试验根均为由上级根通过侧根分支处分为2条下级根的根段,采用TY-8000伺服强力机测定4种植物侧根分支处的抗折力、抗折强度。结果表明：柠条、沙柳、沙棘、白沙蒿的侧根分支处均为试验根的薄弱部位,其抗折能力低于该部位之上的根段,也低于该部位之下的2条下级根;侧根分支处的抗折力与侧根分支处直径为幂函数正相关,抗折强度与直径为幂函数负相关,抗折强度的种间差异为：柠条（31.47±7.68）MPa〉沙柳（17.27±1.90）MPa〉沙棘（3.76±1.07）MPa〉白沙蒿（2.10±0.28）MPa。

英文摘要：

At the vigorous growth period,with the 3-4year-old Caragana korshinskii,Salix psammophila,Hippophae rhamnoides and Artemisia sphaerocephala as the research objects,used the TianYuan-8000 test instrument to test the breaking resistance and the breaking strength of the four plants.The test roots both were that the upper straight root branched two lower straight roots through the lateral root branch.The results showed that the lateral root branch of four kinds of plants all were the weak part of test roots,and its breaking resistance was not as good as the upper straight root and the two lower straight roots.The breaking resistance and the diameter of lateral root branch were the positive correlation of power function,and the breaking strength and diameter were the negative correlation of power function.The breaking strength of the four kinds of plants compared：Caragana korshinskii（31.47±7.68）MPa〉 Salix psammophila（17.27±1.90）MPa〉Hippophae rhamnoides（3.76±1.07）MPa〉Artemisia sphaerocephala（2.10±0.28）MPa.