Study On Salt And Drought Resistance On Aubrieta Cultorum Seeds And Seedlings

This paper mainly researched Aubrieta cultorum seeds and seedlings on salt and droughtresistance with pot experiment. Salt resistance test used five salt treatment level, and the droughtresistance of seeds used PEG simulation experiment, seedlings drought resistance test usedcontinuous drought, testing physiological and biochemical characteristics and ultrastructure.Theexperiments were performed to study Aubrieta cultorum of salt resistance mechanism and themechanism of drought resistance. The results showed that:(1)Salt stress delayed Aubrieta cultorum germination time, and the seed germination ratedecreased. The test used5salt treatments on Aubrieta cultorum seeds, showing that, with theincreasing concentration of salt stress, the germination rate and germination energy of Aubrietacultorum seeds firstly increased and then decreased.(2) Under salt stress, leaf tissue water content of Aubrieta cultorum decreased gradually; therelative conductivity, soluble sugar increased gradually; the content of chlorophyll, solubleprotein, SOD showed a downward trend after the first rise．Aubrieta cultorum seedling leaf netphotosynthetic rate diurnal variation、CO2concentration diurnal change of intercellular、waterusing efficiency presented "Bimodal " curve;The rate of transpiration rate of Aubrieta cultorumreached "Unimodal" curve.By Principal component analysis, under NaCl stress, tissue watercontent, chlorophyll content,SOD,Pn, soluble protein、WUE of several variables, could be usedas indicators of Aubrieta cultorum salt tolerance.(3) Using6concentration levels of PEG to dispose Aubrieta cultorum seed, germinationindex by measuring, the results showed that,5%、10%PEG concentration, the germination rate、germination energy in the normal range;beyond this concentration, the germination rateminimum. Germination of20%,25%PEG almostly inhibited the seed germination rate.As canbe seen through the ultrastructure of the seed PEG treatment of low concentrations of Aubrietacultorum seed would produce some changes, such as a starch grains to resist drought stress, therewas a strong drought resistance.(4) Under drought stress, leaf water content descended continuously; leaf relativeconductivity and soluble protein increased with the prolonging of drought stress time; SOD,soluble sugar increased with the increasing degree of drought stress increased first and thendecreased. The diurnal variation of transpiration rate change、the rate of transpiration rate ofAubrieta cultorum leaf showed " Bimodal " curve; diurnal change of intercellular CO2concentration、 water using efficiency, showed the first decline after rising and fallingtrend.Aubrieta cultorum ultrastructural study of Arabidopsis mesophyll cell chloroplasts,mitochondria, nucleus and organelles under water stress were varying degrees of change,showing that the mesophyll cell organelles tolerance and sensitivity are different.Beeningobserved both chloroplasts, mitochondria organelles could be used as comparative analysisevaluated the cellular level of Aubrieta cultorum drought important reference for.