Study On Nutrient Solution Formula For Cucumber During Fruit-bearing Stages In Soiless Culture

The experiment, in which the optimized regression design was adopted, involving 3 factors, each with 5 leves, were conducted to study the nutrient solution formula for cucumber at Fruit-bearing in Soiless culture. With the aid of computer,the model demonstrating the relationship between yield factor(y) and three element factors the concertration of NKMg were established.The model is as follows:Y=420.17792+6.68322x1+3.54910x2-6.61654x12-4.58407x22-3.6297x32+6.47500x1X2 Analysis result showed that: firstly,the effects of three factors on the yield of cucumber increased by degrees in series of magnesium(Mg),Potassium(K) and nitrogen (N). Secondly, the interaction among three facters existed.The interaction between N and K,N and Mg were significant .There is significant positive interaction between them in low level and significant negative interaction between them in high level. Thirdly, by simulating with computer, to achieve the individual plant yield of 425.7g/plant. The final optimal combination of N, P, K, Ca, Mg could be N 20.35mmol/L, P 1.75mmol/L, K 10.38mmol/L, Ca5.0mmol/L, Mg2.5mmol/L.In the verification experimention with treat A, B, C, D and CK, the chlorophyll content,root vigor,photosynthesis rate,transpiration rate,quality and yield of cucumber that planted with the optimal nutrient formula from the model were superior to CK,and it with the baddish nutrient formula from the model was inferior to CK,that prove the model is accuracy and reliability.In the condition of low temperature and few light in winter,heating the root zone can remarkably accelerate the growth and development of cucumber,only adjusting the nitrogen form have no evident influence. With the treatment of heating the root zone and adjusting the nitrogen form, the effect is more remarkable.