Studies On Alleviate Effects Of Nitric Oxide On Salt Stress And Low Temperature Stress Of Cucumber

Nitric Oxide (NO) is an important active molecule in biology. It is firstly described as a diffusible multifunctional second messenger in animals since it plays various functions including the relaxation of blood vessels, neurotransmission and defense during immune response etc. It is now being evident that kingdom. It germination, was proved to participate in NO is also a ubiquitous signal molecule in plant many key physiological processes such as seed hypocotyls elongation, leaf expansion, root growth, lateral root initialation, programmed cell death, and stress tolerance. However, its disease-resistant physiological mechanisms in plants are still vague at present. Recently, it has been reported that the addition of NO increased the salt tolerance of crops in experiments within weat (Triticum aestivum), maize(Zea mays) and rice (Oryza sativa), lupin(Lupipus luteus) , reed (Phragmites communis trip.). However, information is still lacking regarding the effects of NO on salt tolerance of cucumber (Cucumis sativus L. ) and its mechanism. Therefore, the effects of NO donor on the physiological and biochemical mechanisms in hydroponic cucumber seedlings under salt stress were investigated, in order to clarify the possible mechanisms of enhancing salt-tolerance in plants. The main results were presented as follows:1 Different concentrations of SNP solution can increased the plant height and stem diameter of cucumber seedlings and the adopt consistence is 1.0mmol/L.2 The treatment of SNP can obviously improve the chlorophyll content , improve the root activity and the activity of POD ,reduce relative conductance rate, and decline the content of MDA in leaves of cucumber seedlings under salt stress3 To comparative analysis the three, we can see that at the previous two modes of processing, using the appropriate concentration of SNP can increase adaptability of cucumber seedlings to salt stress. No post treatment was not represented release function in initial stage, but it was shown in late stage. Therefore it can be concluded that all modes of processing can release the salt stress in seedling stage, the best relieve effect is No pretest treat and No seed soak4 SNP can raise cucumber yield in different stage and the adopt consistence was...