| 【Objective】The growth and nutrient characteristics of Pinus massoniana under different nitrogen（N）and phosphorus（P）fertilizer treatments were studied to reveal the nutrient uptake and accumulation of seedlings, which could provide theoretical basis for clarifying the fertilization effect mechanism and the growth theory of P. massoniana.【Method】In the greenhouse, the P. massoniana seedlings were planted in plastic pots. After the emergence of the seedlings, different amounts of N and P fertilizers were applied. Then, after growing for half a year, the plant height, diameter, root system and biomass of the seedlings as well as the nutrient contents of seedlings aboveground and underground were
determined, and the accumulation and transfer coefficient of nutrients were calculated.【Result】There were differences in the fertilizer effects with the application of different amounts of N and P fertilizers, but there was no significant difference in mid-element accumulation of seedlings. The transport coefficient（SAR）of Ca, Mg and Mn under each treatment was greater than 1, while the SAR of Fe, Zn, and Cu under each treatment was less than 1. Under N treatment, the main root of seedling was developed（20.1 cm）, with short total length（63.1 cm）and the ratioof aboveground/underground biomass greater than 2, the macro-elements and mid-elements were assigned to needles, which were beneficial to the accumulation of Cu and Zn（32.26 mg/plant and 21.16 mg/plant）, and Mn uptake of aboveground part was 5.16 times that of the underground part. Under P treatment, the branch root was developed, with short main root（17.2 cm）, maximum diameter（1.00 cm）and the ratio of aboveground/underground biomass less than 1. The application of P fertilizer improved P accumulation in needles of seedlings（11.87 g/plant）, and Mn accumulation of aboveground part（68.89 mg/plant）was 2.57 times that of the underground part（21.01 mg/plant）. Except for Mn, the transport coefficients of other mineral elements were higher than those of N treatment.【Conclusion】Fertilization can promote the growth of seedlings of P. massoniana, and P fertilizer has a significant effect on the branch root. The N fertilizer has an obvious effect on the growth of seedling height, however, it is not beneficial to the growth of branch root. Except for P and Fe, the application of N fertilizer is conducive to the accumulation of nutrients in aboveground parts. The P fertilizer can promote the P absorption in aboveground parts and enhance the transfer of mineral elements except Mn. The application of N, P fertilizer inhibits the accumulation of Fe. |
