Nitrate and nitrite contents in Chinese Leafy cabbage, Chinese water convolvulus and Chinese kale which using chemical fertilizer

Abstract

The study of nitrates and nitrites in Chinese Leafy Cabbage (CLC), Chinese Water Convolvulus (CWC), Chinese Kale (stem type; CKS) and Chinese Kale (leafy type; CKL) treated chemical fertilizer as recommended dose and non-treated fertilizer were conducted between May - September, 2006. Stems, petioles and leaves of the vegetables were analyzed by using spectrophotometric method. The results were found that nitrate contents in whole plants were higher than nitrites. Nitrate contents in vegetables treated fertilizer were significantly more than that in non-treated fertilizer vegetables but nitrite contents were contrast. Nitrate in CLC was highest as 5,249+638 mg./kg. and was higher than nitrate in CKL, CKS and CWC as 4,664+695, 4,449+537 and 3,876+560 mg./kg., respectively. Nitrate difference in CKL and CKS were not significant. Nitrite in CKS was highest as 3.69+1.44 mg./ kg. and higher than CWC, CLC and CKL which were 3.27+1.49, 2.23+0.83 and1.90+0.95 mg./kg., respectively. Nitrates and nitrites in stem and petiole of CLC, CWC, CKS and CKL were significant higher than that in leaves, but nitrites in leaves of CLC, CKS and CKL were not significant difference in stem and petiole. Nitrites in CWC stem and petiole were lower than that in leaves and have not significance.