Research On The Reaction And Mechanism Of Resistance Against Adversity Regulated By Glycinebetaine In Mulberry(Morus Alba L.)

Glycinebetaine(GB) is one of the most important osmotic-regulating chemicals in higher plants and is considered to be involved in plant response to adversity. No report appears regarding its use in mulberry industry . This text covers the prompting effect on the salt- and cold-tolerance of mulberry using exogenous GB and the relevant physiological mechanism under it.The results demonstrate that exogenous GB can be absorbed by the mulberry seed and affect seedling development , with GB of 5-10mmol/l advancing the germination and growth of the plant. GB can raise the germination ratio of seeds under salt-stress, the chlorophylll content in the seedling leaf and osmotic-regulating chemicals content such as proline and soluble sugar. GB can reduce the accumulation of Na~+ in the root, stem and leaf of the mulberry under salt stress and decrease Na~+/K~+, therefore lifting the mulberry'ability to face salt stress. Exogenous GB reduce the plasma membrane injury ratio of mulberry leaf under cold stress, giving rise to high rate of survival of the mulberry seedling under cold stress. This conclusion provide an experimental base of exogenous GB to be used in mulberry cultivation.Based on technology of nuclear magnetic resonance(~1H-NMR), the content of the GB under different conditions can be detected. Results show : there is a certain amout of GB within the mulberry, implying that mulberry belongs to the GB self-made plant species; salt-stress can induce GB; exogenous GB, foliarly applied, can be absorbed by the leaf and transported up- and down-ward. This lies biophysical foundation that GB can lift the mulberry resistance to salt- and cold-stress...