Study On Nitrate Accumulation And Reducing Control Technology Of Characteristic Leaf Vegetables

In order to solve the problems of high nitrate content in the production of characteristic leafy vegetables,this experiment studied the quality difference,the accumulation rule of nitrate in growing period of 13 kinds of characteristic leaf vegetables,and the effects of GABA,glucose,DCD,DMPP and green light on the nutritional quality,nitrate metabolism and photosynthetic characteristics of arugula.The main results in this study are as follows:1.there were significant differences in botanical characters,quality and nitrate accumulation among different characteristic leaf vegetables.Among them,the comprehensive nutrition quality of‘Banye arugula No.1’was the highest,followed by‘Baigeng qianjin’,the nitrate content of‘Baxi endive’was the lowest.During the whole growth process,the nitrate content,nitrite content and nitrate reductase activity of six varieties of arugula,four varieties of endive and three varieties of mizuna mustard showed different changes.Among them,there was a significant negative correlation between nitrate content and nitrate reductase activity.2.Exogenous GABA,glucose,DCD,DMPP and green light treatment all can improve the nutritional quality,promote nitrate metabolism and photosynthesis of arugula,and then reduce the accumulation of nitrate.Among them,the nitrate content of arugula decreased to the lowest on the6th day after exogenous GABA treatment,the correlation analysis showed that the correlation coefficient of nitrate content with NR and GAD activity was the highest,and all reached the extremely significant negative correlation.the nitrate content of arugula decreased to the lowest on the 6th day after exogenous glucose treatment,under this treatment,the nitrate content was negatively correlated with chlorophyll content and P_n.The nitrate contents of arugula was the lowest after 24 hours of continuous green light supplement,under this treatment,the nitrate content was negatively correlated with chlorophyll content and P_n.On the 28th day after DCD and DMPP treatment,the nitrate content was the lowest,under this treatment,the correlation coefficient of nitrate content with chlorophyll content and soil nitrate nitrogen content was the highest,all of which reached a significant negative correlation.3.Combined with the operation convenience,cost,effect stability,safety,nitrate control effect and the effect on plant nutrition quality of the four reducing technologies,it was found that GABA and glucose treatment were more suitable for application in production.In this study,we discussed the effects and mechanism of GABA,glucose,DCD,DMPP and green light on reducing nitrate content of arugula,which can provide theoretical basis for solving the problem of nitrate excess in vegetable production.