Gypsophila Davurica Seed Breeding And Drought Stress On G. Davurica

Currently, Daqing region saline habitats and arid habitat garden plants in resource-poor. Research Daqing grassland under arid habitats ornamental plant species G. davurica. Through breeding, drought tolerance evaluation, provide a scientific basis for scientific promotion and cultivation of garden plants in arid regions application.The study of15,20,25,30℃four temperature gradient, the PEG mass concentration of5%,10%,15%,20%,25%, different concentrations of NaHCO3, NaNO3, NaCl solution and different storage time on seed germination of G davurica; Observation under natural conditions of G davurica seed germination, growth and development of rhythm characteristics. Impact of drought stress on its shape, leaf water content, conductivity, SOD activity, soluble protein content, MDA content, transpiration rate, intercellular CO2concentration, stomatal conductance and net photosynthetic rate, the establishment of scientific research methods. The findings are as follows:(1) The results show that seed germination characteristics of G davurica in the temperature range of15～30℃higher germination rate, more than90%; G davurica seed germination required light is insensitive to light type; PEG mass concentration of5%and10%contribute to G davurica seed germination compared with CK, germination rate was4-6%; Unfavorable for seed germination when the PEG concentration greater than15%; G davurica seed harvest storaged at room temperature after1year, their germination characteristics is not obvious;0.3mol/L concentration of NaNO3and NaHCO3solution treatment is the critical value of the indicators of G davurica seed germination,0.45mol/L concentration of NaCl solution processing is the critical value of G davurica seed germination indicators, and the low concentration(0.05mol/L), to some extent, help to improve the germination capacity.(2) Under natural conditions, seed germination rate of G davurica in the culture medium of the peat soil and sand volume ratio of1:1is the highest, up to85%; A single peat soil under cultivation matrix, plant height, average leaf number, bud the total number and specific leaf weight of G davurica than other culture substrate; G davurica seedlings for growth in a single peat soil environment.(3) In average temperature and humidity, respectively, was27℃and51%of the indoor environment, effects of different concentrations of PEG osmotic stress on the morphology of G davurica leaf water content, conductivity, SOD activity, soluble protein content and MDA content:10%,20%,30%of PEG osmotic stress treatment, respectively, at24h,18h,12h gradually lose ornamental. With the increase of processing time, and its leaf relative water content decreased, no significant change; water saturation deficit values upward trend, minor changes; leaf conductivity and MDA content increases gradually with increasing PEG concentration; leaves SOD activity and soluble protein content first increased and then decreased.(4) Artificial potted water control of drought stress on G davurica shape, leaf water content, conductivity, SOD activity and soluble protein content, MDA content, transpiration rate, intercellular CO2concentration, stomatal conductance and net photosynthetic rate produced a certain impact:G davurica can tolerate drought limit the number of days is25days, its seedlings dry; soil moisture and leaf water content show a downward trend with the increase in stress time; water saturation deficit, conductivity, malondialdehyde and SOD activity is rising; soluble protein content showed an increasing trend, a downward trend after rehydration. Soil water content and leaf net photosynthetic rate, stomatal conductance, intercellular CO2concentration, transpiration rate of G davurica showed a significant positive correlation.