Abstract: The results of the experiment showed that combined application of K,N obviously promoted tomato growth.The fresh weight,dry weight.stem width and leaf area per plant increased with the increasing of K concentration in nutrient solution and showed significant positive correlation.Blooming,fruit setting and cropping date were advanced with increasing of concentration of K and N.The maturation date was 7-10 days earlier than that of low potassium treatment.Average yield per plant,fruit number per plant,weight of single fruit,the rate of high class fruit were increased clearly with the increased concentration of K;but at the end of growth period there was salt accumulation phenomenon in rock wool culture bed in high N and K treatment,this case made the reduction of calcium absorption,increment of bloom end rot and the reduction in yield.The result showed that soluble soild titratable acidity with K concentration were significant correlation.The fruit surface color was a closely correlation with K concentration and was a significantly negative correlation with L b ∗ ,and significantly positive correlation with a ∗ .Increasing of K concentration promoted absorption of N and K in leaf,and increment of N concentration increased the absorption of K and P in leaf,but high K concentration was a trend to reduce the P,Ca,Mg contents in leaf.The result of experiment indicated that the treatment of high N but low K would make symptoms of nutrient unbalance and the yield significant reduced worse than that of low N and low K unless correspondingly increasing the K concentration.The experiment recommended suitable.K concentration 200-300mg·kg^-1 and N concentration 100mg·kg^-1 .In order to gurantee high quality and yields,K concentration could be improved properly in tomato nutrient solution.

Key words: Tomato, Nutrient solution, Potassium nutrition, Nitrogen nutrition, Application of combined fertilizer, Physiological Index, Yield

CLC Number: 

• S641.203