Journal of the Indian Society of Soil Science

A field experiment was conducted on fine loamy, mixed, hyperthermic Udic Haplustalf in the Regional Research Station, Chiplima, Orissa, so as to evaluate the effect of irrigation and nitrogen on sunflower (Helianthus annuus L.) for three consecutive summer seasons from 1992 to 1994. The treatment plan included four irrigation frequencies at 0.6, 0.8, 1.0 and 1.2 IW/CPE in the main plots and four nitrogen doses at 0, 30, 60 and 90 kg N ha⁻¹ in the subplots. The result indicated that application of nitrogen at the rate of 60 kg ha⁻¹ and of irrigation at IW/CPE of 1.0 had significantly increased the seed yield (1391.7 kg ha⁻¹) and Nuptake (37.6 kg ha⁻¹) in seeds of sunflower. The nitrogen use efficiency of the crop was also significantly increased (11.9 kg seed/kg N) by applying irrigation @ IW/CPE of 1.0 and nitrogen fertilizer @ 30 kg N/ha.