Effects Of Short-term Saline-alkaline And Drought Stress On Growth Of Leymus Chinensis Seedling

Leymuschinensis is the main dominant plant in Songnen grassland. As the degree ofincreasing saline-alkaline,decreased rainfall and seasonal drought, environmental conditionsof LeymusChinensis has changed a lot, which has an profound impact on itsgrowingdevelopment.Therefore, in order to provide theory basis for plant which is underdouble stress of saline-alkaline and drought.we adopted simulations of saline-alkaline anddrought double stress to control the experiment,studied theaccommodation limit andcountermeasure of Leymuschinensis seedling to saline-alkaline and drought.Seeding is the primary stage of plant’s living activities,which has higher sensitivity tosaline-alkaline and drought stress.The study will takeLeymuschinensisseedling, aperennialgramineousplant,as material, For salt and drought stress though Saline-alkalinesoil and PEG6000to Leymuschinensis seedling. After stressing for28days, charge seedingsin each treatment group and determine growth indexes.The experimental results show that:1. After growing in adversity for3days, Leymuschinensis seedling will come intoadaptive countermeasures. Accumulation changes of Leymuschinensisseedling’s biomassisperiodic.The more serious the growth environment is,the shorter changeable period will be.The biomass changes of Leymuschinensisseedling is sensitive to water stress,moreover hasstrong resistance to salinity-alkalinity.2.The stress of Saline-alkaline and water,have cumulative inhibitory action to the plantheight of Leymuschinensisseedling. High pH has significateinhibitory action to the plantheight of Leymuschinensisseedling. The consist drought periods of light water stress andsevere water stress,which have the irreversible drought damage to the plant height ofLeymuschinensisseedling, are7days and14days.3. Under the same salinity-alkalinity, severe water stress has the bigger inhibitoryaction than light water stress to the root length of Leymuschinensisseedling. Severe waterstress lasts21days, which is beyond the tolerance range ofLeymuschinensisseedling, bynow, adversity stress on plant damage is irreversible.