Compared with the contrast,we found that the number and size of vascular bundle of the ear stalk and the first stalk in the variation were more, the proportion of area of vascular bundles to stalk tissue,the number of vascular bundles and air cavities in the middle vein of sword leaf increased .All of this showed that the transport tissues of the variation were developed better,the material transportion was more unimpeded and the quality of thematerial transportion in a certain time was more,which were...
