Studies On Physiological Charact Eristics And Physical-Chemical Items Of Different Leaf Positions In Flue-Cured Tobacco

This experiment has studied the change tendency of physiology indexes, the chemical compositions, the physical property and the organizational structure indexes in the different position of tobacco leaf during the mature growth and process of flue-curing for the first time, as well as different nitrogen level had an effect on the correlative enzyme activity of main carbon - nitrogen component. The results indicated as below,1. Among different positions of green tobacco leaf, the water content of mid-rip was the biggest, the second was lateral vein, the third was leaf base, the last were leaf margin and leaf tip; and when it turns to different stalk positions, the water content of tobacco leaf decreased along with the raise of the stalk position, especially the water content of the leaf decreased sharply. In the leaf tobacco the content of MDA and the water content changed by the relation of increasing and decreasing. But the activity of SOD displayed the same tendency with change of the water content. The pigment content decreased gradually with the time increasing after transplanting. Among the different position, the content of pigment increased generally from the leaf tip to leaf base, and increased gradually from leaf margin to the leaf center at the same time; the pigment content is smallest in the mid-rip and the lateral vein, and the difference got 0.05 level for between the mesophyll, mid-rip and lateral vein. Among the different leaf position, the content of pigment increased along with raise of the leaf position at the same time.2. In different period of mature leaf tobacco harvest, the activity of amylase and alpha-amylase general was the highest in the leaf vein, were next in the leaf tip and margin, was the lowest in the leaf base. Generally, the GPT and the GOT in the mesophyll organization were more active than that in the leaf vein, meanwhile the activity of GPT and the GOT were highest in the leaf center, were next in the leaf tip and margin, were lowest in the leaf base among the mesophyll organization. The change rule of GS activity in the different stalk positions was disagreement with that in the different positions of leaf: in the mature time of the lower leaf, the change of...