ABSTRACT

Field experiment was conducted at the Eastern farm of Michael Okpara University of Agriculture Umudike to investigate suitable weeding regime for enhanced growth and development of four cowpea varieties (Vigna unguiculata (L.) Walp). Five weeding regimes: No weeding, weed free, one weeding, two weedings and three weedings were studied for the effect on the growth and development of lT9OK-76, IAR-48, 1T81D-988 and lT89KD-288. The experiment was arranged as a split-plot in Randomized complete Block Design with the cowpea varieties as the main plot and weeding regime as the subplot. Result of the experiment showed that plant height, leaf area and shoot dry weight among the varieties was highly significant (P<O.O1) at 3, 6 and 9 WAP while number of branches per plant was only significant at 9 WAP. Highest leaf area was recorded in the variety IAR-48 followed by lT81D-988 and 1T89KD-288 while the least leaf area was recorded in variety 1T90K-76, and this had an effect to lower the 'weed density and weed dry matter on these varieties. The result further showed that the weed density and weed dry matter were lower in all the cowpea varieties at 6 and 9 WAP. The result suggested that variety IAR-48 and 1T81 D- 988 had the best growth and biological yield at two and three weedings and also have good potentials as cover crops in weed management.