Effect of Component Population on the Growth and Yield of Maize and "Egusi" Melon in Intercrop
Field experiment to determine the optimum component populations of maize (Zea mays L.) and egusi melon Colocynthis citrullus L. Schrad) component crops in intercrop were conducted in 2004 and 2005 cropping seasons. There were three maize populations (17,780; 26,670 and 53,330 plants/ha), three egusi melon population (8,890; 13,330 and 26,670 plants/ha) resulting in nine possible intercrop population combinations. Sole crops of the three planting densities each of maize and egusi melon were included to ease the calculation of land equivalent ratio (LER). Length of egusi melon vine decreased with increase in maize planting density and increased with increasing egusi melon density. Intercropping reduced the yields of maize and egusi melon relative to their sole crops. The presence of egusi melon reduced the grain yield of maize and the seed yield of egusi melon. The grain yield of maize, however, increased as the population of maize in the intercrop increased, while the seed yield of egusi melon continued to decrease with increase in maize population in the intercrop. The LER ranged from 1.40 to 1.84 in 2004 and from 1.48 to 1.68 in 2005 depicting yield advantages of 40 to 84% and 48 to 68% in 2004 and 2005, respectively with the highest yield advantage accruing from intercropping 17, 780 maize and 13,330 egusi melon plants/ha in 2004 and 53,330 maize and 26,670 egusi melon plants/ha in 2005. In both years, the highest monetary returns were obtained with intercropping 53,330 maize and 8,890 egusi melon plants/ha with contribution from maize more than that from egusi melon.
Key words: Component density, Egusi melon, Maize, Intercropping.