Effects Of Sodium Selenite On The Growth And Grains Quality Of Sweet Buckwheat

In order to improve the yield and quality of sweet buckwheat grains.In this study,this experiment used a completely random experiment to design three sodium selenite application methods: soil application(T),spray once application(P1),and spray twice application(P2).There were 5 concentration levels for each selenium application.By measuring the agronomic traits,physiological indexes,photosynthetic parameters,grain quality and selenium absorption of sweet buckwheat grains,the following conclusions were drawn:(1)When the concentration of soil selenium fertilizer was less than 10.00 mg/kg,the plant height,biomass accumulation and yield of sweet buckwheat could be promoted.When the concentration of soil selenium fertilizer was more than 10.00 mg/kg,the inhibition effect was shown.When the concentration of selenium fertilizer spraying was less than 1.00 mg/L,the plant height and yield of sweet buckwheat could be promoted,but the fresh weight of the stem and dry weight of the grains could be inhibited.When the concentration of selenium fertilizer spraying was more than 1.00 mg/L,the inhibition effect was shown.(2)When the concentration of soil selenium fertilizer was less than 10.00 mg/kg,the development of chlorophyll and antioxidant enzymes of sweet buckwheat could be promoted,and the growth of sweet buckwheat could be promoted,but the soil selenium fertilizer did not affect the chlorophyll b of sweet buckwheat.When the concentration of selenium fertilizer was more than 10.00 mg/kg,the inhibition effect was shown.When the concentration of selenium fertilizer spraying was less than 1.00 mg/L,the development of chlorophyll and antioxidant enzymes in sweet buckwheat could be promoted,and the growth of sweet buckwheat could be promoted.When the concentration of selenium fertilizer spraying was more than 1.00mg/L,the inhibition effect was shown.(3)When the concentration of soil selenium fertilizer was less than 10.00 mg/kg,the transpiration rate,net photosynthetic rate and stomatal conductance of sweet buckwheat could be increased and the photosynthesis of sweet buckwheat could be promoted.When the concentration of soil selenium fertilizer was more than 10.00 mg/kg,the inhibition effect was shown.When the concentration of selenium fertilizer spraying was less than 1.00 mg/L,the transpiration rate,net photosynthetic rate and stomatal conductance of sweet buckwheat could be increased and the photosynthesis of sweet buckwheat could be promoted.When the concentration of selenium fertilizer spraying was more than 1.00 mg/L,the inhibition effect was shown.The transpiration rate of sweet buckwheat in the full-bloom stage was inhibited by spraying selenium fertilizer twice.When the concentration of soil selenium fertilizer was less than 10.00 mg/kg and the concentration of selenium fertilizer spraying was less than 1.00 mg/L,the ability of assimilation and utilization of CO2 will be improved by inhibiting the intercellular CO2 concentration.(4)When the concentration of soil selenium fertilizer was less than 10.00 mg/kg,sweet buckwheat grain quality could be improved by increasing the soluble sugar,reducing sugar,starch,protein,flavonoids,rutin and quercetin of sweet buckwheat grain.When the concentration of soil selenium fertilizer was more than 10.00 mg/kg,the inhibition effect was shown;When the concentration of selenium fertilizer spraying was less than 1.00 mg/L,sweet buckwheat grain quality could be improved by increasing the soluble sugar,reducing sugar,starch,protein,flavonoids,rutin and quercetin of sweet buckwheat grain.When the concentration of selenium fertilizer spraying was more than 1.00 mg/L,the inhibition effect was shown.(5)As the growth period of buckwheat prolongs,When the concentration of sodium selenite was less than 10.00 mg/kg and the spray concentration was less than 1.00 mg/L,the application of sodium selenite could improve the anti-aging ability of sweet buckwheat,and alleviate the degree of chlorophyll and photosynthetic characteristics decay during the growth of sweet buckwheat;The effect of selenium on sweet buckwheat was more significant in the full-bloom stage than in other periods.