Study On Manufacturing And Application Of Nutrient Solution For Vegetable Hydroponics

There are many ions like Ca2+, Mg2+, HCO3- in the tap water of ShanXi province. Hence these ions always cause yellow leaves due to lack of iron. Hence we take Hydroponics green-leave vegetable as experimental plant, within five deferent iron forms (FeCl3, FeSO4, FeC6H5O7, humic acid iron, EDTA-Fe), we tried to select one of a best iron fertilizer fit for local water qulity by completely random experiment, in addition, we studied various comparisons of different N-forms and ratios and the effect of photosynthetic bacteria solution on absorbing iron. Based on above we make out optimum prescription suitable for Hydroponics of vegetables in Shanxi.The iron fertilizer screens shows that the humic acid iron (FA-Fe) is cheaper than EDTA-Fe, more excellent than FeC6H5O7, FeSO4 and FeCl3, and it is the best iron fertilizer which is worth popularizing. FA-Fe significantly increased content of chlorophyll, CAT activity and root activity ,significantly increased the content of Vc and reducing sugar, decreased the content of nitrate nitrogen and increased the yields of Lettuce and Celery.The effect of N forms and Ratios on iron nutrition in hydroponically grown lettuce were investigated. It was found that suitable ratio(NO3--N:NH4+-N:CO(NH2)2 =6:6:0) in nutrient solution can significantly promote plant growth, raise chlorophyll content, improve plant iron utilization efficiency, and reduces nitrate content accumulation in leaves, and the cost of nutrient solution was thus reduced.The experiment of PSB liquids shows that the treatment with bacteria is better than that of without bacteria, moreover 10ml liquid is the best. Within three organic irons, FA-Fe is the best. It not only improved the yields of Lettuce, chlorophyll, and reduce nitrate, moreover increase the number of soluble iron and ratio of utility.Nutrient solution compounds experiment shows that Lettuce yields increased by 28.69% chlorophyll by 10.10%, catalase activity by 22.13%, total iron and soluble iron content by 10.53,60.33, nitrate content less 55.25%, overall the activity of iron had been increased. In the perspective of the cost of nutrition, this nutrient solution save 20-30% of the cost. Both the yield and the quality of the vegetable produced have increased in different level. We suggest this nutrient solution prescription should be popularized and applied considering that it may fit for many different green-leave vegetable.