Grápia (Apuleia leiocarpa Vog. Macbride) is an important native forest species that has been in extinction process. The aim of this study was to determine the optimum levels of phosphorus and sulfur fertilization on the initial growth of grápia. Grápia plants were cultivated in pots containing 3.5kg of a Paleudalf soil, under unclimatized glasshouse conditions. Sixteen fertilization treatments were used in a complete bifactorial scheme (4x4), represented by the combination of four levels of P (0, 60, 120, and 180mg kg-1) and four levels of S (0, 10, 20, and 30mg kg-1). The plant growth in height, stem diameter, and number of leaves was analyzed monthly. After 130 days of cultivation other growth parameters were analyzed, as follow: number of fallen leaves, dry weight of roots, stem, leaves, and of the whole plant, and root/shoot dry weight ratio. The dry weight of the whole plant positively responded to the combination of phosphorus and sulfur fertilization, with the maximum technical efficiency level of 204 and 16mg kg-1 of soil, respectively. The phosphorus fertilization above 120mg kg-1 of soil gave rise a chlorosis in leaves similar to that of Fe deficiency. High availability of P in the soil was accounted for best growth of shoots in detriment of roots.
forest species; Apuleia leiocarpa; seedling production; mineral nutrition
