Leaf Vegetables N Nutrition Absorption And Accumulation Law

Leaf vegetables mainly for edible parts, vitamin content is rich, the production mainly regulate the vegetative growth of plants, often a large amount of nitrogen fertilizer in vegetative growth process to need to grow and supply of nitrogen, due to its shorter growth period, once the nitrogen is too large, easy to cause the accumulation of nitrate, if the people after eating in the human body will be converted to nitrite, cause nitrite poisoning, or combined with amine compounds in the body to form carcinogenic nitrosamine compounds, the digestive system cancer formation of carcinogenic nitrosamine poisoning, constitutes a potential threat to human health and ecological environment. Therefore, scientific control nitrogen fertilizer to produce high quality goods and vegetables has become a development important problems needed to resolve. The absorption of nitrogen conversion rate of plant nitrogen absorption ability is an important symbol, directly reflects the plant for nitrogen nutrient absorption and utilization ability, and how to use nitrogen and harvest time but also is closely connected with the nitrate accumulation is discussed in this paper. This experiment with four kinds of representative leaf vegetables as test materials, first of all, through the research of urea under different seems to deal with, to the growth of leaf vegetables, and influence of nitrogen nutrient absorption and accumulation and by urea with different way and the number of processing, to the growth of leaf vegetables, and influence of nitrogen nutrition absorption and make every effort to study at the same time the influence of different harvest time on the nitrate accumulation in the body. To develop a regular physiological indexes, trying to screening, reasonable nitrogen and applied method of leaf vegetables to research provides the theory basis for safe nitrogen fertilizer. Through the test the following conclusions:The increase of nitrogen making leaf vegetables for nitrogen and nitrogen content increased, nitrate accumulation increases, higher chlorophyll content, root activity increased.Production along with the increase of nitrogen increased significantly, but when the Chinese cabbage nitrogen more than20.8g/m2, garden chrysanthemum nitrogen more than24.0g/m2, spinach nitrogen more than22.4g/m2, celery nitrogen is more than37.2g/m2, production no longer increases,and so on.Basal one-off fertilization treatment, and fertilizer and fertilizer once twice, in comparison with the processing of reasonable fertilizer can make plant nitrogen uptake increased significantly, and the absorption of leaf vegetables conversion rate increased significantly, represents the transformation of leaf vegetables absorb nitrogen ability enhancement, to reduce nitrate accumulation. If on the number of fertilizer, parallel comparison, fertilizer treatment twice, nitrate accumulation peak will be delayed, thus affecting nitrate decline, resulting in normal harvest, harvest four leaf vegetables nitrate exceeds bid badly, then suggested that leaf vegetables according to a field with the method of management. When fertilizer, spraying on the leaf with water wet compared two ways, the process of spraying on the leaf, plant absorption of conversion rate was significantly higher than that of wet with the water treatment, can effectively reduce nitrate accumulation.Use select appropriate nitrogen into basal fertilizer and60%40%(spraying on the leaf), to make four leaf vegetables, can be found that nitrate content in harvest when it was just down to safety standards, if4days in advance, harvested four leaf vegetables nitrate content exceeds bid badly, so it is not recommended in the normal consumption of leafy vegetables before harvest, if delay4days harvest, while the growth of leaf vegetables features significantly below delay8days of harvest, but at this time of nitrate accumulation and lowest reach the ideal state, output is the best harvest time.In Chinese cabbage harvest, seems is10.4g/m2, the processing of Chinese cabbage in the nitrate meet safety standards and the highest yield, while more than seems is15.6g/m2, the processing of Chinese cabbage nitrate exceeds bid badly, it is not recommended to eat; Applying garden chrysanthemum when harvested, the content is12.0g/m2, the processing of edible garden chrysanthemum nitrate is in line with safety standards and the highest yield, and the process of applying more than content of18.0g/m2, garden chrysanthemum nitrate exceeds bid badly, it is not recommended to eat; Applying spinach when harvested, the content is11.2g/m2, the processing of eating spinach nitrate content is in line with safety standards and the highest yield, and the process of applying more than content of16.8g/m2, spinach nitrate exceeds bid badly, it is not recommended to eat; Celery, harvested seems to18.6g/m2, the processing, the nitrate content of celery meet safety standards and the highest yield, and the process of applying more than content of27.9g/m2, celery nitrate exceeds bid badly, don’t recommend to eat.