Study On The Effect Of Salt Stress On Seeding Germination And Growth Of T. Mongolicum

Very rich in wild dandelion germplasm resources, the dandelion’s values of being edible, medical andnutritious are gradually paid much attention to and market demand is increasing, consequently, the world isbeginning artificial cultivation and planting of the dandelion. Through research on saline-alkali stress onthe germination of the dandelion seed, one way of dandelion’s artificial cultivation can be opened up and atthe same time it has great practical significance of the modification and utilization of saline-alkali soil.①with seed germination method and Na₂CO₃solution of different concentrations, the dandelion seedis given stress treatment to study the influence of Na₂CO₃stress on the germination of the dandelion Seed.The results show that50mmol/L Na₂CO₃solution has a significant influence on the germination rate of thedandelion seed.5mmol/L Na₂CO₃solution has a significant or extremely significant inhibition on thegermination potential of the dandelion seed, germination index and vigor index.Under the stress of5-150mmol/LNa₂CO₃solution, the dandelion seed can still germinate, whichillustrates the dandelion seed has a certain salt resistance. Water recovery experiment also shows that thedandelion seed has a certain tolerance on Na₂CO₃stress. The characteristics have laid theoreticalfoundation for making full use of properties of saline-alkali soil in Xinjiang to plant the dandelion.②With the20treatment liquids of different proportion made with50,100,200,300mmol/L NaCl,Na₂CO₄, NaHCO3and Na₂CO₃and using Petri dish paper germination method, the dandelion seed’ssaline-alkali tolerance and the reaction under saline-alkali stress are studied. The results show that thegermination rate, germination potential, germination index and vigor index of the dandelion seed areaffected to varying degrees. When mixed saline-alkali solution concentration increases, the degree of seedvigor inhibition was stronger than seed germination rate; when the proportion of alkaline salt NaHCO3,Na₂CO₃in the solution increases, the dandelion germination time delays. When the concentration of avariety of mixed saline-alkali solution reaches100mmol/L, some of the dandelion seed still germinate.When the concentration reaches200mmol/L, the germination of the dandelion is completely inhibited.When the concentration is100-200mmol/L and the proportion of a variety of mixed saline-alkali solutionis NaCl: Na₂CO₄: NaHCO3: Na₂CO₃=1:1:0:0, the germination is severely inhibited and reaches extremelysignificant level.③The experiment studied on the effects of mixture salt on seed germination and seeding growth ofTaraxacum mongolicum Hand-Mazz. Taking20different proportion compound of50,100,150,200mmol/L NaCl, Na₂CO₄, NaHCO3and Na₂CO₃and using river sand as a substrate, seed germination andseeding growth of T. mongolicum were tested under these stress conditions. The result showed that thegermination rate, seedlings on the underground part and fresh weight were different. When the solutionalkaline salt of NaHCO3、 Na₂CO₃ratio increased, the rate of emergence and the underground parts of thedegree of suppression were greater than the part on the ground. When the mixed salt solution concentrationwas100-150mmol/L, some seeds of T. mongolicum germinated. When the concentration was200mmol/Lit can not grow. The concentration was50mmol/L mixed with NaCl: Na₂CO₄: NaHCO3: Na₂CO₃=1:2:1:0,it germinated improved. When concentration was100-200mmol/L mixed with NaCl: Na₂CO₄: NaHCO3:Na₂CO₃=1:1:0:0, it can not germinate completely. T. mongolicum tolerates to mixed salt stress andappropriate mixed salt stress contributes to the seed emergence of T. mongolicum. Stress effect of alkalinesalts is greater than that of the neutral salt. With concentration increasing, stress effect of alkali solution isgreater than that of alkaline salt.