Nitrogen management efficiency against sunflower (Helianthus annus L.) under different irrigation frequencies

A field trial to examine nitrogen management efficiency against sunflower under varying irrigation frequencies was performed during 2015 at Agriculture Chemistry (Soils) Section, ARI Tandojam. Four N levels (0, 50, 100, 150 kg ha-1) and four irrigation frequencies (2, 3, 4, 5 irrigations) were evaluated in RCBD with three replicates. The response of sunflower crop to varying N rates and irrigation frequency in relation to growth, seed yield and oil content was significant (P<0.05). Apart from the crop growth traits, sunflower seed yield was highest (2520.90 kgha‑1) with 41.73% oil content; while seed yield decreased to 2268.90 kg ha‑1 and oil content increased (42.09%) under 100 kg ha-1 N over 150 kg N ha-1. The N @50 kg ha-1 remained least in all the growth and seed yield traits. Similarly, 04 times irrigated sunflower produced highest seed yield (2198.80 kg ha‑1) and oil content (41.10%); while 05 times irrigated crop showed relatively lesser seed yield (1953.40 kg ha‑1) and oil content (39.71%). The seed yield responded superbly to higher N (150 kg ha-1) with maximum seed yield (2520.9 kg ha-1) but oil yield slightly decreased; while 04 times irrigated crop resulted in highest seed yield (2198.8 kg ha-1) and oil content (41.10%). Keywords: Sunflower; Nitrogen efficiency; Irrigation frequency; Seed yield; Oil content http://dx.doi.org/10.19045/bspab.2017.60059