Effects Of Controlled-release Fertilization Rate On Container Seedling Growth And Nutrient Storage Of Four Exotic Oaks

Reasonable fertilization especially nitrogen fertilizer in the nursery period,can effectively improve the quality of seedlings.Compared with the water-soluble fertilizer,the controlled-release fertilizer has the advantages of one-time application,the nutrient is gradually released,the nutrient requirement of the plant can be satisfied,the manpower cost,nutrient leaching,and environmental pollution are reduced.It is important to introduct exotic species to improve species diversity and landscape of China.There are lots of work in terms of acclimation and adaptability after the introduction of Quercus,but the research on seed fertilization is relatively few.In this experiment,five fertilizers of 25,100,150,200 and 400 mg N/strain were used to study the effects of fertilization on the growth and nutrient storage of Quercus seedlings and to find out the best controlled-release fertilizer application of those Quercus seedlings.Experiment result shows:1.The optimum fertilization rate of Quercus rubra is 400 mgN/strain.The N concentration of root was 1.83%,the P concentration of root was about 0.41%,the K concentration of root was 0.84%,the N concentration of stem range from 1.31%,the P concentration of stem was 0.27%,K concentration of stem was 0.45%.2.The optimum fertilization rate of Quercus suber is 200 mgN/strain.The heiht of seedling is 19.0 cm,the diameter of root is 4.68 mm.The N concentration of root was 1.41%,the P concentration of root was 0.30%.the K concentration of root was 0.70%,the N concentration of stem was 1.07%,the P concentration of stem was 0.26%,K concentration of stem was 0.44%.3.The optimum fertilization rate of Quercus coccinea is 150 mgN/strain.he heiht of seedling is 14.8 cm,the diameter of root is 4.14 mm.The N concentration of root was 1.36%,the P concentration of root was 0.29%.the K concentration of root was 0.78%,the N concentration of stem was 0.95%,the P concentration of stem was 0.24%,K concentration of stem was 0.49%.4.The optimum fertilization rate of Quercus palustris is 400 mgN/strain.The heiht of seedling is 31.6-32.8 cm,the diameter of root is 4.83 mm.The N concentration of root was 1.66%,the P concentration of root was 0.21%,the K concentration of root was 0.81%,the N concentration of stem range from 1.18%,the P concentration of stem was 0.17%,K concentration of stem was 0.34%.