Objective:To probe and identify the ultramicro
characteristics of trachea inner walls(TIW)of six species of
Sect.Stenophora,i.e.,Rhizoma
Dioscoreae Spongiosae,Rhizoma Dioscoreae Hypoglaucae,Rhizoma Dioscoreae Futschauensis,Rhizoma Dioscoreae Gracillimae,Rhizoma Dioscoreae Tokoro and Rhizoma Dioscoreae Zingiberensis,by scanning electron microscope (SEM).Method:The vertical microscopical sections are stuck on the platform of species and metal plated.TIW were observed and photographed by SEM.Result:The ultramicro
characteristics of TIW,i.e.,the smoothnesss of TIW,the existence of separation bands,the density,arrangement types,shapes and sizes of pits,etc., can be seen clearly under SEM.Further,there exist differences in the ultramicro characteristics of each species.Conclusion:The above six species of crude drugs can be identified according to their ultramicro characteristics of TIW.SEM can be used to study the ultramicro characteristics of crude drug rhizomas thus creating a new area for identifying crude drugs.