The Effect of Phosphorus on the Growth and Productivity of Mexican Marigold (Tagetes minuta L.)

Field trials were carried out in Sadra town near Shiraz, Iran in 2010 to determine the effect of phosphorus (P) on the productivity of Mexican Marigold (Tagetes minuta L.), an important medicinal plant. Phosphorus was band-placed at the rates of 0, 40, 80 and 120 Kg/ha at planting time. Results indicated that growth parameters and essential oil concentration increased with increasing the P levels. Application of 120 kg/ha P significantly increased the fresh and dry weights, plant height and flower numbers per plant. All P as compared with the control significantly enhanced the essential oil concentration. Moreover the role of phosphorus as a central and pivotal metabolic and regulatory nutrient element has been discussed.