Crescimento e produ??o de pinh?o-manso (Jatropha curcas L.) sob doses de fósforo

摘要

This study aimed to evaluate the influence of phosphorus on the growth and yield of physic nut (Jatropha curcas L.). Physic nut seedlings, two months old were transplanted in February 2007. In June 2008 it was held in drastic pruning all plants in height of 80 cm of soil. The treatments consisted of P2O5 doses: 0, 50, 100, 150 and 200 g-1 pit. The experimental design was a randomized block with four replications of eight plants, totaling 40 plants per block. The evaluation period of the experiment it was realized between October 2008 to October 2009 (corresponding to the 2nd year of assessment), and between October 2009 and October 2010 (corresponding to the 3rd year of assessment), and the evaluated variables: the number of branches prior to pruning, the number of branches after pruning, the number of branches in inflorescence, number of inflorescences plant 1, the number of branches with clusters, the number of clusters plant-1 and productivity. Pruning stimulated the growth and production of physic nut. The increase in phosphorus fertilization increased the productivity of physic nut, reaching a stable starting dose of 150 g ha-1 of P2O5. The cultivation of physic nut can be considered a species that responds to fertilization.