| The morphological structures of Melilotoides ruthenica roots, stems and leaves collected from six different sources were studied. The results primarily indicated that its leaf size, leaf colour, stomatal density, cell size and palisade tissue compactness could be used as the indictors of its drought resistance. Of the seven materials used in the experiment, the two materials collected from the Wulanchabu League of Inner Mongolia were more drought resistant than the other materials and thus could be used as the breeding germplasm in future. |