Potassium sources and doses in the fruit production and essential oils content of coriander

Resumo

Potassium is the second most required element by plants, and commonly is applied as potassium chloride. However, due to its high chlorine content and losses in the quality of the final product, this fertilizer is not recommended for certain crops and is replaced by potassium sulphate. Thus, the aim of the present study was to evaluate coriander fruit production, macronutrient content and essential oil and linalool content in fruits submitted to different potassium sources and doses. The experiment was conducted in a randomized block design in a 2x4 factorial arrangement, applying two potassium sources (chloride and potassium sulphate) at four doses (50, 100, 150, 200 mg K kg^-1 substrate) with four replicates. The highest fruit yields and phosphorus and sulfur contents were obtained in coriander plants fertilized with potassium sulfate. Essential oil content in the fruits was increased when applying K₂SO₄, with the highest value obtained at the estimated dose of 153.8 mg kg^-1 K, while for linalool contents this was estimated at 131.3 mg kg^-1 K. Thus, the application of potassium sulphate increases the number of coriander fruits, their fresh mass and essential oil content.