Growth and nutritional efficiency of acacia seedlings in response to phosphate fertilization

Acacia mangium Willd cultivation is a viable option to meet the growing demand for wood in the forest market. However, there is little information related to its nutritional requirements in the seedling growth phase. The objective of this study was to evaluate the growth and nutritional efficiency of acacia seedlings in response to phosphate fertilization. The experimental design was completely randomized with five treatments, and with five replications each. The treatments consisted of five phosphorus (P) doses: 0, 50, 100, 150 and 200 mg dm(-3), and triple superphosphate (46% P2O5) was used as the mineral source. The plant height, stem diameter, leaf number, shoot, root and total dry matter, P content in leaves, stem and roots, and P efficiency of uptake, translocation and use were subsequently evaluated 120 days post-transplant. The rate of 150 mg dm-3 of P showed the best growth and efficiency results for P use. The increases observed in acacia seedlings due to the increase in P rates show the importance of adequate phosphate nutrition in the development of this species. Thus, 150 mg dm(-3) of P is the recommended rate for Acacia mangium seedling cultivation.