Effect of irrigation scheduling, conjunctive use of water sources and fertilizer levels on yield and water productivity of groundnut (Arachis hypogaea)

A field experiment was conducted for 2 consecutive years 2008–09 and 2009–10 at Deras, Mendhasal, Odisha, to study the effect of conjunctive use of water sources and fertilizer levels on yield and water use of winter (rabi) season groundnut (Arachis hypogaea L.). The treatments included 3 levels of conjunctive use of water [C₁-(2 irrigations through canal water only, C₂-2 irrigations with canal water + 1 irrigation with ground water and C₃-2 irrigations with canal and 2 irrigations with ground water)] and 5 fertilizer treatments, [(F₀, no NPK; F₁, 100% NPK (20, 40 and 40 kg/ha as N, P₂O₅ and K₂O), F₂, sugarcane trash bio-compost (STBC) alone (1 t/ha); F₃, 75% NPK + sugarcane trash bio-compost (0.25 t/ha) and F₄, 50% NPK+ sugarcane trash bio-compost (0.50 t/ha)]. Pod and haulm yields of groundnut were significantly increased with conjunctive-use of water sources (ground and canal water) compared to canal water irrigation alone. The increase in pod yield was 45.3% and haulm yield 40.3% with conjunctive use of 2 irrigations through canal and 2 irrigations through ground water over 2 irrigations with canal water. This treatment also gave the maximum gross returns (47, 714/ha), net returns (35, 166/ha) and benefit: cost ratio (2.80). With application of 75% NPK + STBC (0.25 t/ha) 70.3% and 73.4% increase in pod and haulm yields was observed compared to the control (no fertilizer application). The highest water use (434 mm), water-use efficiency (5.06 kg/ha-mm) and benefit: cost ratio (3.11) were recorded with application of 75% NPK + STBC (0.25 t/ha).