Effect of molybdenum and manganese on nitrate reductase activity,nitrate content

and nutrient quality in Brassica campestris ssp.chinensis were studied using solution

culture by spraying Mo and Mn elements on leaf,root and leaf combined with root

treatment.The results indicated that nitrate reductase activity was significantly improved

by Mo treatment,which caused significant reduction of nitrate content.Although,no

remarkable effect on improving nitrate reductase activity was found by Mn treatment,nitrate

content was also reduced.Both Mo and Mn could improve the contents of soluble sugar and

VC.Compared with single treatment of Mo or Mn,the reduction of nitrate content,improvement

of soluble sugar and VC contents were more distinct by treatment with Mo plus Mn.