Effect Of Different Nitrogen, Potassium, Calcium Levels On Tomato Grown In Substrate

In order to increase the yield and improve quality of tomato, an experiment related tonutrient solution formula monitoring was performed since September2011in theexperimental station of plant protection college in Shandong Agricultural University. To solvethe problems of low yield, poor quality, navel rot of tomato, a trial using nitrogen, potassium,and calcium as experimental factors, was performed by single factor experiment, using theorthogonality way to design nutrient solution formula.The experiment was supposed to selectthe most suitable nutrient solution formula for local soilless cultivation of tomato,explore thenutritional properties of tomato under soilless cultivation, and thus providing theoreticalsupport and technical parameters for preparation and management of nutrient solution.The main results were as follows:1.When N concentration in nutrient solution is11mmol/L, the height and stem width oftomato plant in each growing stage, fruit yield per plant (3879.70g), Vc content (159.89mg/kg)and NO3-content (74.38mg/kg) in tomato fruit, were significantly higher than thoseof LN and HN treatments (P <0.05). LN treatment is beneficial to the accumulation ofsoluble sugar in fruit (64.25mg/kg). HN treatment is suitable for the growth of tomato plants(height, leaf area, chlorophyll content of leaves), but it made plants displayed the signs ofmoderate growth and inhibit the reproductive growth of tomato. Within the scope of thisexperiment, the effect of N concentration on total acidity was not significant when comparedto CK. Considering each index of tomato plants and fruit, it is concluded through theorthogonal experiment that the appropriate concentration of N in nutrient solution for growthand development of tomato is N211mmol/L.2.When the concentration of K in the nutrient solution is HK8.4mmol/L, the heightand stem width of tomato plant in each growing stage, total leaf area (0.62m2),chlorophyllcontent, fruit yield per plant(4567.33g), Vc content(163.65mg/kg), total acidity (0.46%),NO3-content (69.28mg/kg) in tomato fruit were significantly superior to LK and HKtreatments (P <0.05). Within the scope of this experiment, the effect of K concentration onsoluble sugar was not significant. Considering the index of tomato plants and fruit, it isconcluded through the orthogonal experiment that the appropriate concentration of K innutrient solution for growth and development of tomato is K3level8.4mmol/L.3. When the concentration of Ca in the nutrient solution is3.75mmol/L, the nutrition indicators of tomato plants, such as the height and stem diameter in flowering and fruitingperiod of plant, total leaf area (0.51m2) were significantly higher than other treatments.When the concentration of Ca in the nutrient solution is HCa4.5mmol/L, the indexes offruit yield and quality, such as fruit yield per plant (4110.33g), Vc (168.97mg/kg), the totalacidity (0.41%) were significantly higher than other treatments. Within the scope of thisexperimental, the effects of Ca concentration on the contents of soluble sugar andchlorophyll were not significant. It is concluded through orthogonal experiment that theappropriate concentration of Ca for high yield is Ca1level3mol/L, so the concentration ofCa in the nutrient solution can be kept to be3mmol/L, added to be3.75mmol/L by foliarapplication of fertilizer in vegetative growing stage, and added to be4.5mmol/L in thereproductive growth period.4. The appropriate nutrient solution formula for tomato is: N11mmol/L,K8.4mmol/L,Ca3mmol/L. P1.5mmol/L, Mg1.0mmol/L, S2.5mmol/L,is the same to the content ofHolland nutrient formula and the fomula of trace elements is the common formula.