Effect of nitrogen and boron on growth and yield attributes of sunflower (Helianthus annuus L.)

A field experiment was conducted on response of summer sunflower to nitrogen and foliar application of boron at Students’ Farm, College of Agriculture, Rajendranagar, Hyderabad during summer season of 2009 with an objective to work out the optimum and economic level of nitrogen in relation to boron nutrition to summer sunflower. The treatments consisted of three levels of nitrogen (60, 90 and 120 kg/ha) and each level with the combination of boron spraying at 0.1, 0.15 and 0.2% along with one additional treatment i. e. 90 kg N+hand pollination. In total, there were 10 treatments laid out in randomized block design replicated thrice. The results of the experiment indicated significant influence of treatments on plant growth, yield attributes and seed yield. Maximum growth was manifested at 120 kg N/ha+0.2% boron spray. Similarly, the yield attributes and seed yield of sunflower were also significantly improved due to application of nitrogen at higher levels in combination of boron spray indicating maximum values of yield attributes and the highest seed yield with 120 kg N/ha+0.2% boron spray. The highest yield of 1534.6 kg/ha was realized with 120 kg N/ha+0.2% boron spray which was more by 318.3 kg/ha over the lowest level of nitrogen i. e. 60 kg N/ha+0.1% boron spray. There was marginal increase in the yield attributes and yield due to increase in level of boron spray from 0.1 to 0.2% when compared at a given level of nitrogen. The advantage of hand pollination was not seen over boron spray treatment.