Responses of sunflower (Helianthus annuus L.) to irrigation and nitrogen fertilization rates


ZEMDIRBYSTE-AGRICULTURE, vol.100, no.2, pp.151-158, 2013 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 100 Issue: 2
  • Publication Date: 2013
  • Doi Number: 10.13080/z-a.2013.100.019
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.151-158
  • Keywords: economic optimum nitrogen rate, Helianthus annuus, irrigated and non-irrigated conditions, quality, sunflower, yield, YIELD COMPONENTS, GROWTH, HYBRID
  • Bursa Uludag University Affiliated: Yes


This study was conducted to determine the effects of different nitrogen rates (0, 40, 80, 120, 160, 200 and 240 kg ha(-1) N) on the yield, its components and the quality characters of sunflower (Helianthus annuus L.) and to identify the economic optimum N rate for maximum profit under both irrigated and non-irrigated conditions during a 2-year period (2007-2008). As the N rates increased, all of the traits measured significantly increased, except the crude oil content, under both irrigation treatments. Based on the 2-year average, the highest seed yield (2713.6 to 2751.2 kg ha(-1)) and crude oil yield (1012.7 to 1042.5 kg ha(-1)) were obtained using 160 kg ha(-1) N and the higher N rates, with increases of 47.8% and 39.4%, respectively, compared to the control (0 kg ha(-1) N). Similar trends were also obtained for the other traits, except the crude oil content, which was the highest (39-41%) at 0 kg ha(-1) N but the lowest (36-38%) under the higher N rates. The highest mean values for the crude protein content and 1000-seed weight were obtained under the highest N rates (200 and 240 kg ha(-1) N). In 2007, the economic optimum nitrogen rate (EONR) for sunflower was 148.5 kg ha(-1) N under non-irrigated conditions, as compared with 190.0 kg ha(-1) N with irrigation. In 2008, the EONRs for sunflower under non-irrigated and irrigated conditions were 145.1 and 176.7 kg ha(-1) N, respectively. Although the EONR for irrigated conditions was approximately 30-40 kg ha(-1) N more than that for non-irrigated conditions, the seed yield under the irrigation conditions was approximately 65-79% higher compared with the non-irrigated conditions. As a result, it was determined that the economic optimum N rate for sunflower was 145-150 kg ha(-1) N under non-irrigated conditions and 177-190 kg ha(-1) N under irrigated conditions.