It showed the different cultural solutions under the same habitat,it turned out to be: the number of leaves in both Hoagland solution and tap water sustained,while in urea solution presented downward-tendency;the number of roots were increased at the water solutions,while the effect of tap water was better than Hoagland solution,however in urea solution presented downward-tendency.

The changes of the antioxidant enzyme activity, such as superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) were researched through nutrient solution culture.

Optimization of processing parameters on high protein nutrient solution;

Production of soybean peptide nutrient solution by using enzyme to digest defatted soybean flakes;

Simulation of nutrient solution system control based on grey prediction model;

Study on food nutrient contents and preparation of nutrient liquid of swim bladder in Muraenesox cinereus;

The methods for extracting nutrient components of kelp-including polysaccharides, microelements such as Iodin, Calcium, and so on-by acid hydrolyzation, optimizing the relish of kelp nutrient liquid and producing the kelp jelly were studied.

A set of automatic control system controlled by single chip controller have been developed The hardware and software of the system are designed It is verified through experiments:this automatic control system of nutrient liquid providing is considered suitable to automatically irrigate in facility agriculture and it can reach producing requirement,low cost and high reliability.

This paper takes the breeding of tomato nutrition liquid as an example of studying the recirculating nutrient control in the greenhouses.

A nutrition liquid with perfect proprortions and concentration was main factor of nutrition.