关键词: 苦荞, 褪黑素, 生理特性, 产量, 品质

Abstract: The effects of different concentrations［0 μmol/L（CK），50 μmol/L（T1），100 μmol/L（T2）and 150 μmol/L（T3）］of melatonin（MT）on physiological characters，yield and quality of tartary buckwheat were studied，so as to provide a theoretical basis for the application of MT in tartary buckwheat.The results showed that spraying MT could significantly increase grain weight per plant（there was no significant difference among T1，T2，T3 treatments）and soluble sugar content（T1 treatment was the highest） in grains of tartary buckwheat，and significantly reduce the content of malondialdehyde in leaves，but at the same time，decrease the content of soluble protein in leaves at 14 and 21 days after spraying.In addition，T1 treatment could significantly increase stem diameter，contents of flavonoid and total free amino acid in grains of tartary buckwheat，T2 treatment could significantly increase the number of grains per plant and the content of soluble protein in grains of tartary buckwheat，and T3 treatment could significantly increase the number of grains per plant and the content of flavonoid in grains of tartary buckwheat；However，T2 treatment could significantly reduce the thousand‑grain weight and reducing sugar content in grains of tartary buckwheat，and T3 treatment could significantly reduce the content of total free total amino acids in grains of tartary buckwheat.The method of fuzzy membership function was used to comprehensively evaluate the effects of different treatments，and the comprehensive evaluation values of CK，T1，T2 and T3 treatments were 0.451 8，0.572 3，0.494 4 and 0.500 3，respectively，so T1 treatment was the best，followed by T3 treatment. In summary，50 μmol/L MT isbeneficial to tartary buckwheat production.

Key words: Tartary buckwheat, Melatonin, Physiological characters, Yield, Quality