Effects of spacing and water control on growth and yield performance of irrigated rice in Guinea savannah Agro-ecological zone

Abstract

The adoption of some attributes of the system of rice intensification (SRI) like water control and planting distance may help improve the productivity of rice. The aim of this study was to use water supply and plant density, components of SRI, to improve rice yield and reduce water use. The study was conducted at Golinga irrigation scheme. Continuous and Intermittent flooding served as main plots in a split-plot design. Four plant spacing, 20 x 20, 25 x 25, 30 x 30 and 40 x 40 cm, were used as subplot treatments. Water control and planting distance interaction significantly (P=0.001) influenced plant height where intermittent flooding promoted taller plants in narrow and wider planting distance (20 x 20 cm and 40 x 40 cm). Days to 50% flowering lengthened with increasing planting distance. Tiller and reproductive tiller number per plant were influenced by only planting distance (P=0.001) and the numbers increased with increasing planting distance. Dry root weight was significantly influenced by both water control (P=0.001) and planting distance (P=0.001). Intermittent flooding induced better root development. (0.678 kg/hill) than continuously flooding (0.598 kg/hill). Root development also improved with increasing planting distance, from 0.37-0.90 kg/hill. Panicle number per unit area, paddy grain yield and straw weight were significantly influenced (P=0.001) by planting distance with 25 x 25 cm giving the best performance. Paddy yield of 5.2 ton/ha at a planting distance of 25 x 25 cm was above the national average and within the potential yield of the variety.  It can be concluded that intermittent and continuous flooding gave a similar performance. Increasing plant spacing helps to improve individual hill performance but beyond 25 x 25 cm planting distance, the benefits at the individual hill performance are offset by reduced plant density.