Response of Okra (Abelmoschus esculentus (L.) Moench) and Weeds to Plant Spacing and Weeding Regime in a Humid Forest Agro-Ecology of South-Eastern Nigeria

Field experiment was carried out in late 2015 and repeated in early 2016 cropping season at the Teaching and Research Farm of the University of Port Harcourt, Choba, Rivers State, Nigeria to determine the appropriate spacing and weeding regimes for okra production. Three spacing (60 cm x 15 cm, 60 cm x 20 cm and 60 cm x 30 cm) and three weeding regimes [no weeding, weekly weeding, and twice at 3 and 7 weeks after planting (WAP)] were used. The experimental design was a 3 x 3 factorial scheme laid out in a Randomised Complete Block Design (RCBD) with three replications. The results showed that plant spaced at a closer spacing of 60 cm x 15 cm suppressed weeds better than other spacing in both years of study. Okra performance was better at closer spacing of 60 cm x 15 cm than in other spacing regimes. Similarly, weedy check had higher weed growth and least performance than other weeding regimes. There was significant interaction between spacing and weeding regimes. Plant spaced at closer spacing of 60 cm x 15 cm combined with weekly weeding plots had the lowest weed density and dry weight of 0.00 plants /m2 and 0.00 g/m2 in both years of study. While 60 cm x 30 cm combined with no weeding gave the highest weed density and dry weight (395.00 plants/m2 and 306.33 plants/m2) and (88.33 plants/m2 and 95.33 g/m2) in the late and early 2015 and 2016 cropping seasons respectively. The interaction effect further showed that the highest fresh pod yield was obtained from plant spaced at 60 cm x 15cm with weekly weeding ( 3.02 t/ha and 2.26 t/ha) followed by 60 cm x 15 cm with twice weeding at 3 and 7 WAP (2.96 and 2.22 t/ha). While, plant spaced at 60 cm x 30 cm with no weeding had the lowest fresh pod yield (0.08 t/ha and 0.03 t/ha). Since, the yield obtained from 60 cm x 15 cm with twice weeding (3 and 7 WAP) was not statistically different from 60 cm x 15 cm weekly weeding, for economic considering the former could be recommended.