PRODUCTIVITY OF SORGHUM (Sorghum bicolor L.) UNDER INCORPORATED LEGUMES AND NITROGEN FERTILIZATION IN SEMI-ARID ENVIRONMENT

Abstract

Sustainable crop production can be achieved in a cropping system that facilitates a renewable source of nutrients for sustainable soil fertility and productivity. The study was carried to evaluate the influence of incorporated legumes and nitrogen application on productivity of sorghum (Sorghum bicolor L.). Field experiments were carried out in the wet seasons of 2015 and 2016 at the Research Farm of Federal University Dutsin-Ma, Nigeria. The treatments consisted of four levels of N (0, 30, 60 and 90kg N ha -1), and four legumes (Lablab (Lablab purpureus), Mucuna (Mucuna pruriens), Soybean (Glycine max L. Merrill), and Cowpea (Vigna unguiculata L.)) and no legume. SAMSORG 40 variety was used in this experiment. The experiment was laid out in a randomized complete block design and replicated three times. Nitrogen application significantly (P<0.05) increased yield components and grain yield of sorghum. In combined mean, application of 30, 60 and 90kg N ha-1 gave 32.3, 89.2 and 75.5% increases in sorghum grain yield over zero N treatment, respectively. Increasing N rate beyond 60 kg N ha-1 did not significantly increased sorghum grain yield. Application of 60kg N ha-1 was adequate for sorghum productivity in the study area. Incorporation of lablab, mucuna, soybean and cowpea significantly (P<0.05) influenced yield components and grain yield of sorghum. In combined mean, incorporation of lablab, mucuna, soybean and cowpea gave 17.9, 2.1, 25.7 and 21.7% increases in sorghum grain yield over no legume treatment, respectively.
Incorporated soybean produced significantly higher sorghum grain yield than no legume control.