Anatomical Structure and Physiological Characters of Leaves for Cymbidium sinense in vitro

The mesophyll in leaves of Cymibidium sinense does not differentiate into spong and palisade tissue. Morphological changes have taken place in the mesophyll near midrib for the different parts of leaves. The cells of mesophyll near midrib in the apex and the middle part of leaves enlongated in length and differentiated into palisade-like tissue, whereas the cells of mesophyll in the base were not enlongated in length. The size of chloroplast in the apex of leaves is the biggest one in comparison with other parts of leaves, and it has higher content of chlorophyll. The apex parts of leaves have higher photosynthetic rate, and its Fv/Fm, ΦPSⅡ and q p are also higher than other parts of leaves.