Path analysis and percentage contribution of different growth characters to pod yield of groundnut (Arachis hypogaea L.) at Kadawa,Sudan savanna,Nigeria

Irrigated trials were conducted during the dry seasons of 2004, 2005 and 2006 at the Irrigation Research Station of the Institute for Agricultural Research (IAR), Nigeria, to study the performance of three groundnut (Arachis hypogaea L.) varieties as affected by basin size and plant population. Treatments consisting of three basin sizes (3 × 3, 3 × 4 and 3 × 5 m), three plant populations (50,000, 100,000 and 200,000 plants ha^?1) and three varieties (Samnut 11, Samnut 21 and Samnut 23), were laid out in a split-plot design with factorial combination of population and variety assigned to the main plots and basin sizes to the subplots. Plant height exhibited the highest positive (p ≤ 0.05) effect of 0.3993, 0.5124, 0.6296 and 0.5897, followed by total dry matter (0.2339, 0.3329, 0.4040 and 0.4197) and number of branches (0.1118, 0.0181, 0.0416 and 0.1541) in the three years and when combined. Path coefficient analysis revealed that among the growth characters selected, plant height made the highest positive contribution of 34.77% to pod yield of groundnut, followed by total dry matter with a positive contribution of 17.46%, suggesting plant height was the most critical growth parameter for determining yield of groundnut under irrigation.