Effects Of Controlled-release And Common Compound Fertilizers On Growth And Quality Of Tomato And Sweet Pepper Plug Seedlings

Aimming at the crucial problems of the high costs, high labor intensity, serious environmental pollutionin in vegetable seedlings, the study using tomato, sweet pepper analyzed, and a trial was conducted to evaluate the effects of controlled-release and common compound fertilizers with various rates in nursing media on grouth, sound seedling index, floral bud differentiation and fertilizer use efficiency of tomato and pepper seedings using no fertilizers, nutrient solution and equal rate of NPK common compound fertilizers as controls. The findings provided a theoretic support basis for improving the processing thchniques, and exploring the intensive utilization of CRFs. the research results were as follows:1. Early in the tomato and pepper seedlings, the growth tendency of treatments of CCF was the best, but with the growth and development and its constant release nutrient, CRF can meet the nutrient demand of later period of vegetable seedlings. Having increased the height and stem diameter, enhanced the root absorption capacity of seedlings. Compared with nutrient solution and CCF, The treatment of equal rate of NPK controlled-release and common compound fertilizers had the best effects on biomass and sound seedling index: biomass of tomato seedlings increased by 7.3% and 5.2% respectively, and pepper was 16.5% and 11.9%; sound seedling index of tomato seedlings increased by15.5% and 10.8% respectively, while pepper that was 20.1% and7.1%. When the rate of NPK controlled-release and common compound fertilizers reduced by 20%, biomass and the sound seedling of tomato and pepper seedlings had the same good effects as nutrient solution and common compound fertilizers.2.The coated CRF was meet demand in plant was it supplied by its constant release nutrient. In the course of growth of the plants, especially the later period, had promoted the absorption of the nutrient of plants: the content of chlorophyll, Pn, NR activity , root activity, anti-cold performance of treatments of CRF1 was higher than treatments of nutrient solution and CCF; while nutrient content was reduced by 20%, CRF could meet the nutrient requirement of tomato and pepper and while nutrient content was reduced by 30%, seedling quality was lower.3.Except the trentments of CK, the C/N ratio of all the other trentments of tomato and pepper seedling leaves was in between 1-1.4 and the C/N ratio of treatments of CRF1 was highest. Tomato and pepper seedling leaves of treatments of nutrient solution, CCF, CRF1, CRF2 and CRF3 had higher carbohydrate content and N content, The study showed that CRF could promoting buds tosplit up and playinga role in enhancing quality of seedlings.4.CRF has the fuction of controlling nutrient release, so basal application controlled-release fertiltzer in seedlings could meet the nutrient demand of whole period of tomato and pepper. Compared with nutrient solution and CCF, accumulation of N, P, K loss for tomato and pepper seedlings was reduced Significantly. Seeing from nutrient absorbing of plant organs, accumulation of N, P, K absorption for the treatment of equal rate of NPK controlled-release was the highest, when the rate of N, P, K controlled-release and common compound fertilizers reduced by 20%, tomato and pepper still had better growth. Seeing from N utilization, CRF improved vegetable N absorbing and N use efficiency, quantity of CRF was applied more fewer and N utilization more higher, for tomato, N utilization was 58.43%-68.37%,30.4 and 27.5 percentage higher than that of nutrient solution and CCF. While for pepper, that was 60.37%-76.25% respective, 31.9 and 35.9 percentage higher. Besides, CRF improved vegetable P and K absorbing and use efficiency, that indicated CRF play a role on the interaction of N, P, K.