Effects Of Seed Soaking With Chemical Regulators On Eco-physiological Indices Of Tartary Buckwheat In Different Water Conditions

Drought stress is one of the important reasons affecting plantgrowth and yield increase. Chemical regulators are used for soakingseeds to improve crop’s drought-resistant ability, which has theadvantages of simple operation, no pollution, and quick effect.Tartary buckwheat is nutritive, can care health, and can be used tomake medicine. Its growth period is short, and it is very tenacious inthe extremely cold weather, so it is adaptable. What’s more, it is themainly crops in Shanxi Province, especially in the cold areas in Shanxi.In this paper, the “Heifeng No.1” tartary buckwheat is used asexperimental materials. Potted tartary buckwheat and PEG droughtsimulation tests are used to study the effects of the differentchemical regulators on tartary buckwheat seedling growth and yield,which are under the normal irrigation, moderate drought and severedrought. The results are as follows:(1) Socking seeds with different concentrations of uniconazolecan reduce the plant height of the tartary buckwheat under differentwater conditions, but can improve the stem diameter, leaf area, totallength of root and seedling index of the tartary buckwheat. Meanwhile, chlorophyll content, SOD activity, POD activity, leafrelative water content, praline content, soluble sugar content, solubleprotein content, root activity and photosynthetic parameters(Pn, Tr,Ci and Gs) of tartary buckwheat leaves are increased. Dealing withuniconazole can reduce the content of MDA in tartary buckwheatleaves, which result in the strengthen of the degree of membrane lipidperoxidation. It also can increase the activity of protective enzyme.Under drought stress, various physiological and ecological indexes ofthe tartary buckwheat all change. After socking seeds withUniconazole, the range abilities are all inferior to those of the tartarybuckwheat which are soaking with H2O, and the range of soaking with80mg/kg uniconazole are the least. At the same time, the effectivebranches number, number of spikes, grains of plant and the100-seedmass of the tartary buckwheat is the largest. All of these indicatethat soaking seeds with uniconazole can increase the droughtresistance of the tartary buckwheat seedlings, and also can improveits yield under drought stress.(2) Socking seeds with different concentrations of rare earth canincrease the germination energy, germination rate, sprouting index,vigor index, germination stress index, sprouting index ofdrought-resistance, chlorophyll content, SOD activity, POD activity,leaf relative water content, praline content, soluble sugar content,soluble protein content, root activity and Chlorophyll fluorescenceparameters(Fm, Fv, Fv/Fm, Fv/F0,qN and qp) of tartary buckwheat. Italso can decrease the height of the seedlings and the content of MDA.Under drought stress, various physiological and ecological indexes ofthe tartary buckwheat all change. The range increases with the degree of the drought stress. However, after socking seeds with rareearth, the range are inferior to those of the tartary buckwheat whichare soaking with H2O. The range of socking seeds with200mg/kg rareearth are the least, so we can say the drought resistance of seedlingssocked with200mg/kg rare earth are the strongest.(3) Znso4, Mnso4, SA, Pro all have the promoting effects on thetartary buckwheat’s growth and yield. Which shows as follows:promote stem diameter, leaf area, total length of root and seedlingindex, chlorophyll content, SOD activity, POD activity, leaf relativewater content, praline content, soluble sugar content, solubleprotein content, root activity, Chlorophyll fluorescence parameters(Fm, Fv, Fv/Fm, Fv/F0,qN and qp) and yield of tartary buckwheat,decrease the content of MDA and leaf relative conductivity, in termsof all indicators, the effects on tartary buckwheat’s droughtresistance from big to small are: SA> Znso4> Mnso4>Pro.