Effect of Nitrogen and Phosphorus on Growth and Yield of Cowpea [Vigna unguiculata L.

Abstract

A field study was conducted during the growing season of 2021 at the crop research farm of the Department of Agronomy at Sam Higginbottom University of Agriculture, Technology, and Sciences, Prayagraj in the North Eastern plains of Eastern Uttar Pradesh with the objective of studying the effects of nitrogen and phosphorus on growth, yield, and economics of cowpea (Vigna unguiculata L.) Var. Gomati VU 89 under a randomised block design, comprising of 9 treatments, of which treatments (T1-T9) with different combinations of nitrogen and phosphorus, which are replicated thrice. The experimental results revealed that 25 kg N/ha + 50 kg P/ha recorded Maximum plant height (69.02 cm), number of branches/plant (12.33), number of nodules/plant (4.0), highest plant dry weight (15.32 gm), crop growth rate (4.80 g/m2/day), test weight (18.57 g), number of pods/plant (20.13), number of seeds/pod (15.1), seed yield (1243.97 kg/ha), harvest index (32.0%). T9 25 kg N/ha + 50 kg P/ha resulted in a higher net return (34.05 x 103/ha), gross return (63.44 x 103/ha), and benefit-cost ratio (2.16).