Abstract
In view of the relative importance of Sesamum indicum, as a good source of oil and medicinal plants in Africa, the production of good quality and high yielding varieties is highly desirable. The pot experiment was conducted at Ogbomoso in the southwestern Nigeria to determine the level of K fertilizer needed for the maximum seed yield and quality of three sesame varieties. The treatments used included four levels of potassium fertilizer (0, 15, 30 and 45kg K20 ha-1) and three varieties of sesame namely; Pachequero, Panshin and C-K2. These twelve treatments were assigned into a completely randomized design fitted into a factorial experiment with three replications. The plant growth and yield attributes such as plant height, number of leaves, number of flowers, and number of seeds per pod significantly (P<=0.05) improved with increased rate of potassium fertilizer with optimum value obtained at 30kg K20 ha-1. K application significantly (P<=0.05) affected the seed yield and yield components of the three sesame varieties with optimum values obtained at 30kg K20 ha-1. The quality and nutrient elements compositions significantly increased with optimum values obtained when 30 kg K2 0 ha-1 was applied. Therefore, 30kg K20 ha-1 could be applied to sesame on the less productive soils in Ogbomoso. Although all sesame varieties used recorded better performance in this agro-ecological zone, C-K2 showed an outstanding seed yield performance with or without K fertilizer applications. However, the best variety in terms of seed quality was pachequero.
