Effects of Nitrogen, Potassium and Weed Interference on Yield of Onion (Allium cepa L.) at the Sokoto Rima Valley

Abstract

Two field trials were conducted during the 2005/2006 and 2006/2007 dry seasons under irrigation at the Usmanu Danfodiyo University Teaching and Research Fadama Farm at Kwalkwalawa, Sokoto (Latitude 130 1’N and Longitude 50 13’E, 350 m above sea level) to study the effects of potassium, nitrogen, and weeding regimes on the bulb yield of onion (Allium cepa L.). The treatments consisted of three levels of potassium (150, 200 and 250 kg/ha), three levels of nitrogen (50, 100 and 150
kg/ha) and three weeding regimes (weedy check, 4 and 6 WAT) laid out in a Randomized Complete Block Design (RCBD) with three replications. Parameters studied included bulb weight (g), bulb diameter (cm) and bulb heights (cm). The result indicated significant (P<0.05) effect of potassium, nitrogen and weed interference on the yield of onion. Highest bulb yield was obtained with 250 kg/ha potassium, 150 kg/ha nitrogen and the 4 WAT weeding regime. No bulbs of marketable value were found under the
weedy check. Based on the findings of this study, it could be concluded that for optimum bulb yield of onion at Sokoto Rima Vallley, a combination of 250 kg/ha potassium, 150 kg/ha nitrogen coupled with weeding at 4 WAT is the most suitable.

Keywords: Nitrogen, potassium, weed interference, onion, Sokoto, Rima Valley