Response of Sesame (Sesamum indicum L.) to Potassium and Sulfur Application at Kafta Humera District, Western Tigray, Northern Ethiopia

Potassium and sulfur are among the most important nutrients limiting sesame production. EthioSIS soil testing map indicate that nutrients such as K and S are deficient in the study site. Study was carried out to investigate response of sesame to K and S application at Humera Agricultural Research Center, Kafta Humera district, Tigray, Ethiopia in 2016 main cropping season. Treatments consisted four levels of potassium (0, 20, 40 and 60 kg K2O ha-1 as KCl) and four levels of sulfur (0, 20, 40 and 60 kg ha-1 as CaSO4.2H2O). The experiment was laid out as Randomized Complete Block Design (RCBD) in factorial arrangement with three replications using Setit-1 sesame variety. Soil sample was taken, result of soil analysis revealed that the soil was clayey textural class, neutral in soil reaction (pH = 7.35), low organic matter content (0.73%), very low total N (0.03 %) and very low available P (0.74 mg kg-1), high soil cation exchange capacity (CEC) (40 cmol(+) kg-1), medium exchangeable K (0.26 cmol(+) kg-1) and low extractable sulfur (4.78 mg kg-1). Maximum sesame grain yields (1371.67 kg ha-1) was obtained from plot treated with 20 kg K2O ha-1 + 40 kg S ha-1 which resulted 145.3% increase over the control plot`s yield. From plots fertilized with K and S levels at a rate of 20 kg K ha-1 and 40 kg S ha-1 was obtained higher yield of sesame. It is conclude, therefore, it will be good to promote K and S for further demonstration.