Effect of crop spacing regimes on weed growth and performance of cowpea (Vigna unguiculata (L.) in a humid zone of South-Eastern Nigeria
Field experiment was conducted at the Department of Crop and Soil Science Demonstration Plot, Faculty of Agriculture, University of Port Harcourt, Nigeria between August and December 2017 to determine the effect of crop spacing regimes on weed growth and cowpea variety IT90K-277-2 performances in the humid zone of Southeastern Nigeria. The treatments consist of three crop spacing regimes: 75cm x 25cm, 75cmx 30cm and 75cm x 35 cm. The treatments were laid out in a randomized complete block design (RCBD) and replicated four times. Results showed that crop spacing regimes had no significant (P > 0.05) effect on weed growth, in all the growth and yield traits of cowpea data assessed, except for stand counts. Therefore, intermediate spacing (75cm x 30cm) or wider spacing (75cm x 35cm) at two stands per hill is recommended to farmers for better weed control and higher grain yield of cowpea in the humid zone of Southeastern Nigeria because either of the spacing tends to be more economical than close spacing, since, no seeds were wasted. However, the study need to the repeated with economic analysis of the crop spacing regime as a variable to revalidate the results obtained from this study.
Keywords: Cowpea, humid zone, spacing, variety IT90K-277-2, and weed growth