Effect of Controlled Release Fertilizer on the Quality of Dianthus caryophyllus L. Seedlings

【Objective】 In this study, a series of substrate formula modulated with long-acting controlled-release nitrogen fertilizer (urea formaldehyde foam) and active phosphorus fertilizer were used to analyze the effects of different fertilizer ratios on the quality of Dianthus caryophyllus seedlings, which provided theoretical basis for fertilization technology of D. caryophyllus. 【Methods】The height and crown diameter of D. caryophyllus planted with modulated substrates were measured at 0, 15 and 30 d, respectively, and the whole plants were harvested at the 30th day for the analysis of biomass, the amount of nitrogen and phosphorus accumulation in above-ground part and root morphology indicators. 【Results】 At the 30th day, all the measured indicators (biomass of leave, stem and root, total root length, total root surface area, total N and P of above-ground part) of T4 treatment (annual flower matrix added with compound fertilizer 1.6 kg/m3, slow release fertilizer 1.14 kg/m3, active phosphorus 5.71 kg/m3, urea formaldehyde 6.05 kg/m3 as the cultivation substrate)reached the maximum values, and such indicators had significant difference with those of CK treatment (annual flower matrix added with compound fertilizer 4.8 kg/m3, slow release fertilizer 3.6 kg/m3 as cultivation substrate). All the measured indicators (biomass of leave, stem and root, total root length, total root surface area, total N and P of above-ground part) of T4 treatment were 3.12 g/plant, 1.75 g/plant, 0.82 g/plant, 5.15 m/plant, 526 cm2/plant, 179 mg/plant and 21.32 mg/plant, respectively. 【Conclusion】Substrates modulated with controlled-release nitrogen fertilizer (urea formaldehyde foam) and active phosphorus fertilizer had significant effects on the growth of D. caryophyllus. In consideration of biomass, total root length, total root surface area, nitrogen and phosphorus accumulation of the above-ground part, the growth effect of D. caryophyllus seedlings under T4 treatment is the best, which not only can obtain better morphological indicators, but also improve the accumulation of nitrogen phosphate fertilizer.