Effect of plant spacing on seed yield and yield components in kenaf ( Hibiscus cannabinus ) variety, Ifeken 400

Plant spacing required for optimum crop productivity depends on morpho-physiological traits between varieties, and the interaction between genotype and the environment.  Studies were conducted in Ibadan (7°38’N 3°84’E) Nigeria, at the Institute of Agricultural Research and Training (IAR and T) during 2006 and 2007 to determine the influence of row spacing on seed yield in  kenaf  variety, Ifeken 400, bred for adaptation to the South Western Nigeria agro-ecologies. The experiment was carried out using split plot experimental design with two inter-row spacing (25  and 50 cm) as main plot and five intra-row spacing (5, 10, 15, 20 and 25 cm) as sub-plot. Results showed that plant height was not influenced by the inter-row or intra-row spacing. Height ranged from 1.91-2.03 m in 2006 and 2.31-2.58 m in 2007. Mid stem girth varied significantly within inter and intra-row densities, while butt girth increased with intra-row spacing. Number of capsules was not influenced by the intra-row spacing. An average of 25 and 18 capsules per plant were recorded in 2006 and 2007 respectively. Although, 100 seed weight (g) was not influenced by inter or intra-row spacing, it was lower in 2006 (0.44 g) than in 2007 (2.21 g). Seed yield was highest from 50 cm inter-row spacing and 20 cm intra-row with 260 kg/ha and 540.5 kg/ha in 2006 and 2007 respectively. The difference in seed yield between the row spacing was significant in 2007. However, it was observed that time of planting and rainfall pattern in 2007 has more effect on higher seed weight and seed yield than in 2006.   Key words: Kenaf, row spacing, seed yield, plant height, stem girth.