The aim of this work was to evaluate the influence of phosphorus and semi-decomposed chicken manure on capitula yield of Calendula officinalis L. The studied factors were five doses of phosphorus (4.3, 25.8, 43.0, 60.2, and 81.7 kg ha-1 P2O5) in the triple super phosphate form and five doses of semi-decomposed chicken manure (1000, 6000, 10000, 14000, and 19000 kg ha-1). The Plan Puebla experimental matrix was used to combine phosphors and chicken manure, which resulted in nine treatments, viz. 25.8 + 6000, 60.2 + 6000, 25.8 + 14000, 60.2 + 14000, 43.0 + 10000, 4.3 + 6000, 81.7 + 14000, 25.8 + 1000, and 60.2 + 19000 (first figure representing kg ha-1P; second figure, kg ha-1chicken manure) in randomized block design with four replications. Final average heights of plants at 120 days were about 60.0 cm, independently of the treatments. Maximum yield of pot marigold capitula was 9755.16 x 10³ ha-1, which was obtained with the use of 49.15 kg ha-1 P2O5 associated to 13401.10 kg ha-1 chicken manure. The highest yield (11058.89 kg ha-1)of fresh biomass of pot marigold capitula was obtained with 49.98 kg ha-1 P2O5 and 13266.59 kg ha-1 chicken manure. Maximum yields of dried mass of capitula (2227.61 kg ha-1) were obtained with 39.62 kg ha-1 P2O5 and 8109.75 kg ha-1 chicken manure. It was concluded that to obtain the greatest dried mass yield of capitula, which constituent the most important commercial product of pot marigold, the plant must be cultivated using fertilization with H" 40 kg ha-1 P2O5 and H" 8000 kg ha-1 chicken manure.
Pot marigold; mineral fertilization; organic residue
