Research Of Drought Stress And Salinity-alkalinity Stress On The Seeds And Seedings Of Orychophragmus Violaceus

In the experiment,Orychophragmus violaceus was used as the experimental material to study the characteristics of physiology and biochemistry under drought and mixed salinity-alkalinity stress.The main results are shown as follows:1.Through the determination of germination index,we come to a conclusion that the seeds' Germination rate of Orychophragmus violaceus reached normal levels under PEG of certain concentration.In 50g/L 100g/L concentrations,the Germination rate is in the normal range.The 200g/L,250g/L concentrations almost inhibit the germination of the seeds.Mild drought stress inhibited the germination of the seeds to a certain extent,severe drought stress completely inhibited the germination of the seeds.2.In the process of soil drought stress, as the stress of drought was intensified and last, the relative water content of leaves and the chlorophyll contents had a descending trend; the penetration of membranes,the accumulation of proline andprotein content increased in varying degrees; with the increase of drought stress degree, the activities of SOD presented to rise first and then drop.After the release from drought, the leaf physiological parameters return to the unscared level.Orychophragmus violaceus have proved resilient so far to adverse circumstances.3.With the increase of stress time and the mass fraction of the mixed salinity-alkalinity,the seeds' Germination rate of Orychophragmus violaceus has a descending trend.In Group 1,the germination rate declines smaller.The result revealed that Orychophragmus violaceus can grow in Group 1.But in the other two groups, the inhibitory action enhance.In Group 3,the stress inhibit the seeds' Germination rate of Orychophragmus violaceus obviously.4.With the increase of stress time and the mass fraction of the mixed salinity-alkalinity,he relative water content of leaves and the chlorophyll contents had a descending trend graduately;Membrane permeability and the content of MDA inceased,approximately ascended first and then descended.The content of Soluble Protein,Proline ascended frist and then descent.,8d, reached a maximum.The activities of SOD has a descending trend.5.Through the observation in the experimental process, and the comprehensive analysis of the results of every index, revealed that Orychophragmus violaceus has better drought resistance and Saline alkali tolerance.