Effect of integrated nutrient management on weed infestation, growth and field of cowpea varieties (Vigria unguiculate L.) in moist savanna of Nigeria

Abstract

A field experiment was conducted during the late cropping seasons of 2018-2019 at the Teaching and Experimental Research Farm of the School of Agriculture and Agricultural Technology, Federal University of Technology, Gidan-kwano campus, Minna. The aim was to evaluate the effect of five various nutrient(s) combinations (Control, 30kg urea N, 30kg urea N + Agrolyser, Rhizobium inoculant Gw5, 30kg urea N + Agrolyzer + Rhizobium inoculant Gw5) on weed infestation, growth and yield attributes of three cowpea (Vigna unquiculata L.) varieties (Kanado white, sampea 15 and sampea 16). The results showed that the local check (kanado white) had the lowest weed infestation, higher leaf number and leaf area index per plant, higher pod weight and grain yield per plot which were not statistically different (P<0.05) from sampea 16 compared to sampea 15. Application of 30kg urea N significantly increased leaf number, leaf area index, dry shoot weight and nodule number per plant compared to application of 30kg urea N + agrolyzer + rhizobium inoculant Gw5 while the Rhizobium inoculation significantly increased pod number per plant, dry pod weight and grain yield per plot compared to the control. Thus, the application of 30kg urea N can be recommended for enhancing the growth parameters while rhizobium inoculation can be recommended for enhancing the yield parameters.