Nutrition DRIS diagnosis of Camellia oleifera leaves in hilly area of South Sichuan

The macro, medium and trace nutriet elements in the leaves of mature Camellia oleifera stand in hilly area of South Sichuan were diagnosed, the nutritional status of C. oleifera was investigated, and the suitable fertilizing range of each nutrient was summarized, which provided theoretical guidance for the scientific fertilization of C. oleifera stands in this region. The leaves of C. oleifera sampled from a mature stand in the hilly area of South Sichuan were used for the determination of contents of nine nutrients (N, P, K, Ca, Mg, Cu, Zn, Fe and Mn), and the nutrient requirement order of this C. oleifera stand was obtained by the establishment of the DRIS nutrition diagnosis system for C. oleifera leaves, and the DRIS nutritional diagnosis system for C. oleifera leaves was also built. The results showed that the nutrient requirement order of this C. oleifera stand was Ca>Zn>Mn>P>Mg>Cu>N>Fe>K; the suitable content ranges of various nutrients were obtained, that is, N 10.978-15.456 g·kg⁻¹, P 0.469-1.271 g·kg⁻¹, K 0.959-8.844 g·kg⁻¹, Fe 0.076-0.257 g·kg⁻¹, Zn 8.390-24.477 mg·kg⁻¹, Cu 2.790-5.980 mg·kg⁻¹, Mn 1.151-90.485 mg·kg⁻¹, Ca 2.056-10.054 g·kg⁻¹, Mg 0.796-1.677 g·kg⁻¹. Conclusion: In the hilly area of South Sichuan, these nutrients, i.e. K, Fe, N and Cu were relatively abundant, while the remaining five nutrients, i.e. Ca, Zn, Mn, P and Mg in Camellia oleifera leaves were relatively deficient, which should be taken more consideration when fertilizing.