Journal of Hunan Ecological Science

【Objective】In order to analyze the response of tree growth and bark content of medicinal components of Magnolia officinalis var. biloba to the formulation of nitrogen, phosphorus and potassium fertilization in the high fertility area, as well as to determine optimal nitrogen, phosphorus, and potassium fertilizer application rates. 【Method】Taking 5-year-old Magnolia officinalis var. biloba as the research object, field experiments were conducted using a nitrogen and phosphorus and potassium “3414” fertili- zation scheme to determine the height and diameter growth of trees in different treatments, as well as the content of medicinal components such as magnolol, honokiol, and total phenols. A fertilizer effect model for tree height growth was established by fitting, and the optimized fertilization amount was determined using frequency analysis method. 【Result】The average values of tree height growth, ground diameter growth, and the content of honokiol, magnolol, and total phenols in the treatment fertilized with nitrogen, phosphorus, and potassium formulations of Magnolia officinalis var. biloba were increased by 84. 56% , 48. 74% , 3. 40% , 3. 10% , and 3. 21% , respectively, compared to that of the no-fertilizer treatment. The effects of nitrogen, phosphorus, and potassium on tree height and ground diameter growth were all N>P>K. The effects on bark magnolol, honokiol, and total phenolic content were all K>N >P. The effects of nitrogen, phosphorus, and potassium on tree height growth were positive, and there was a posi- tive interaction between nitrogen and phosphorus, nitrogen and potassium, and phosphorus and potassium. 【Conclusion】The fertilizer application rate for maximum tree height growth of Magnolia offici- nalis var. biloba in the high fertility area was 128. 63 g / plant of nitrogen fertilizer, 79. 84 g / plant of phosphorus fertilizer, and 54. 63 g / plant of potassium fertilizer, and the maximum growth of tree height was 129. 91 cm. The optimal fertilization amount was 98. 12 - 123. 31 g / plant for nitrogen fertilizer, 60. 23-74. 78 g / plant for phosphorus fertilizer, and 41. 62-51. 24 g / plant for potassium fertilizer. The predicted average height increase for trees was 121. 22 cm.

Magnolia officinalis var. biloba; formula fertilization; growth; medicinal component;fer- tilizer effect