| 【Objective】Based on the research results and the relationship between plant nutrition and fertilizer,
balanced fertilization was carried out to improve productivity and fertilizer utilization rate of Camellia nitidissima and
C. japonica, and provide theoretical basis for the cultivation and conservation of understory plants. 【Method】 By
using C. nitidissima and C. japonica as experimental materials, the contents of nitrogen, phosphorus and potassium
in C. nitidissima and C. japonica under different canopy closures were determined, and the DRIS method was used
to analyze the nutritional index and nutrient status of C. nitidissima and C. japonica under Illicium verum forests of
different canopy density. 【Result】 The contents of total nitrogen and total phosphorus in the leaves of C. nitidissima
showed an increasing-decreasing trend with the increase of canopy density, and they were the largest at a canopy density of 0.7. The total N, P and K contents in the leaves of C. japonica and total K content in the leaves of C. nitidissima
showed an increasing trend with the increase of canopy density, and they were the largest under the canopy density of 0.9.
According to the Diagnosis and Recommendation Integrated System (DRIS), the order of fertilizer requirements of the two
plants under various canopy density was different. The orders of fertilizer required for C. nitidissima in full illumination, canopy
density of 0.5, canopy density of 0.7 and canopy density of 0.9 were showed as K ＞ P ＞ N, N ＞ P ＞ K, K ＞ N ＞ P and P
＞ N ＞ K. The order of fertilizer required for C. japonica in full illumination, canopy density of 0.5, canopy density of 0.7, and
canopy density of 0.9 were showed as N ＞ P ＞ K, K ＞ P ＞ N, K ＞ N ＞ P, K ＞ N ＞ P, P ＞ K ＞ N. The NII (nutrition
imbalance index) of C. nitidissima showed as: canopy density 0.9 ＞ CK ＞ canopy density 0.7 ＞ canopy density 0.5 and that
of C. japonica showed as: CK ＞ canopy density 0.5 ＞ canopy density 0.9 ＞ canopy density 0.7. 【Conclusion】 According to
the NII values of the two plants, it can be concluded that C. nitidissima and C. japonica have the optimal balance of nutrients
at the canopy density of 0.5 and 0.7, respectively, which are suitable for the growth of C. nitidissima and C. japonica. However,
there are some differences in soil nutrient status and fertilizer requirement between two plants under different canopy density. In
production, reasonable fertilization should be carried out according to the actual canopy density. |
