Time of transplanting and spacing effects on growth and yield of rice (Oryza sativa L.) under rainfed in the Northern region of Ghana

Abstract

Abstract

Rice productivity in the Guinea Savannah zone of Ghana is constrained by inappropriate transplanting age and plant spacing, which affect growth and yield formation. This study evaluated their combined effects on rice performance under rainfed conditions. A field experiment was conducted using a 4 × 5 factorial arrangement in a randomized complete block design with three replications. Treatments consisted of four planting spacings (20 × 20, 25 × 25, 30 × 30, and 35 × 35 cm) and five transplanting ages (14, 21, 28, 35, and 42 days after planting). Data were collected on growth traits, yield components, and grain yield. Significant interactions were observed between transplanting age and spacing. The highest biomass (2.16 kg mm −2 ) was recorded at 14 days after planting with 20 × 20 cm spacing. Panicle production peaked at 21 days after planting under 35 × 35 cm spacing. The maximum grain yield (7,810 kg ha − 1) was obtained at 21 days after planting combined with 20 × 20 cm spacing. The findings indicate that rice yield is strongly influenced by the interaction between transplanting age and spacing. Early transplanting at 21 days combined with optimal closer spacing enhances grain yield, suggesting that integrated crop management practices are essential for improving rice productivity in the Guinea Savannah zone of Ghana.