Yield of fáfia [Pfaffia glomerata (Spreng.) Pedersen] with chicken manure, with or without the use of phosphorus incorporated to the soil

The aimed of this study was to evaluate the effect of of chicken manure and phosphorus incorporated to the soil on growth and yield of fáfia. Treatments were five doses of chicken manure (0, 5, 10, 15 and 20 t ha-1), with and without the use of phosphorus (200 kg ha-1 of P2O5, in triple superphosphate form), arranged in 5 x 2 factorial scheme in randomized block design with four replications. Plant heights varied as a function of chicken manure doses, which the highest (138.50 cm) under 20 t ha-1. Yields of fresh and dried weight of leaves, stems and roots were influenced significantly by the interaction chicken manure x phosphorus. The highest yields of fresh and dried leaves (597 kg ha-1 and 100 kg ha-1, respectively) were obtained with the dose of 20 t ha-1 of chicken manure, without the use of phosphorus. For stems, the highest yields of fresh and dried weight (7.757 kg ha-1 and 2.633 kg ha-1, respectively) were obtained with the dose of 20 t ha-1 of chicken manure, with the use of phosphorus. The highest yields of fresh and dried weight of roots (9.065 kg ha-1 and 377 kg ha-1, respectively) were obtained with the dose of 20 t ha-1 of chicken manure, without the use of phosphorus. Average contents of N, P and K of leaves were 8.60; 0.88 and 4.46 g kg-1, respectively. Contents of Ca and Mg were maximum (7.56 and 5.12 g kg-1, respectively) with the use of 20 t ha-1 of chicken manure, independent on the use of phosphorus. In roots, average contents of N, P and Mg were 2.74, 0.27 and 0.96 g kg-1, respectively. K content reduced linearly with chicken manure doses and of Ca was maximum with the use of 20 t ha-1. For obtaining the highest yields of fresh and dried weight of leaves and roots, the fáfia plants must be grown with chicken manure (20 t ha-1) incorporated to the soil within the use of phosphorus.

Brazilian ginseng; medicinal plant; organic residue