To reduce the nitrate content in lettuce under the conditions of aeroponic during summer,this study investigated the effects of different concentrations of glycine[0(CK),1,3,5,7 mmol·L-1]as a substitute for nitrate on the agronomic traits,biomass,and quality of lettuce,based on the South China Agricultural University formula B for leafy vegetables.Principal component analysis(PCA),multiple linear regression models(MLR),and analysis of variance(ANOVA)were employed to analyze the agronomic traits of lettuce treated with different concentrations of glycine.The results showed that the leaf length could serve as an evaluation index for the growth status of lettuce.As the concentration of glycine substituting nitrate in the nutrient solution increased,the nitrate content in lettuce significantly decreased,accompanied by a gradual deterioration of its growth conditions.When the concentration of glycine was 5 mmol·L-1,the nitrate content in lettuce was 401.33 mg·kg-1,which meets the raw food standard(＜432 mg·kg-1).Furthermore,the contents of VC,soluble sugars,and amino acids were significantly higher than the control,while the aboveground fresh mass remained comparable to the control.Consequently,this formulation can be recommended as a nutrient solution for aeroponic cultivation of lettuce during summer.
维普
万方数据
