Response of vegetable cowpea (Vigna unguiculata (l.) Walp. Sub species unguiculata) to planting date and fertilizer nitrogen in the humid tropics.

Abstract

Two factorial experiments were conducted in a randomized block design (RCBD) with three replications to study the responses of vegetable cowpea (Vigna unguiculata subspecies unguiculata) to different plant dates (May, June and July in 1998 and April, May, June and July in 1999) and various nitrogen fertilizer levels (0, 50 and 100 kg/ha in 1998 and 0, 25, 50 and 100 kg/ ha in 1999) at Umudike in the forest zone of south-eastern Nigeria. Delay in sowing date depressed while nitrogen application up to 100kg/ha increased the plant growth attributes of height, leaf area index and dry matter yield. Delay in sowing date from April to July significantly reduced the yields and yield components of pod and seed. Application of 50kg/ha was sufficient to produce high pod and seed yields. The implications of the findings are discussed.

Journal of Applied Chemistry and Agricultural Research Vol. 7 2000-2001: pp. 95-103