Optimization of nutrient solution formula applied in cucumber cultivation with substrate.

[Objectives]We expand the test in order to get the nutrient solution formula for the cucumber cultivation with substrate and its corresponding nutrient solution management solution.[Methods]As test materials to mini-cucumber deltastar,a quadratic regression mathematical model of yield and three factors(N,K,Ca) was set up by the method of quadratic regression response surface design.[Results]The results showed that three factors had certain effects on mini-cucumber yield,and the order of the influence was: N,K,Ca.There were obvious interactions between N and K(P0.01).However,the interactions between Ca and N,K were not significantly different(P0.05).The multivariate quadratic egression model of the yield of mini-cucumber and N,K was highly significant(P0.01).The optimal nutrient solution formula was that the nitrogen level was 20.67mmol·L-1,the potassium level was 10.58mmol·L-1and the calcium level was 4.54mmol·L-1.Under this condition,the yield of mini-cucumber was 638.8 g per plant.The results of verification test showed that plants in the treatment of the optimal nutrient solution formula(20.67mmol·L-1N,1mmol·L-1P,10.58mmol·L-1K,4.54 mmol·L-1Ca,2mmol·L-1Mg) grew well in the blossom period.The net photosynthetic rate and the transpiration rate of three positions were obviously higher than other treatments.The fruit quality of the treament was significantly better than other treatments and the yield per plant was the highest.[Conclusions]Through the establishment of quadratic regression mathematical model for the optimal nutrient solution formula of cucumber cultivation,this paper should provide the theoretical basis and technical support for practical applications.