Investigation of combined effect of biological and chemical fertilizers of phosphorus and nitrogen on quantitative and qualitative characteristics of sunflower (Helianthus annuus L.)

In order to study the combined effect of biological and chemical fertilizers of phosphorus and nitrogen on quantitative and qualitative characteristics of sunflower, this experiment was conducted as a factorial based on a randomized complete block design with three replications in a field in Izeh County during 2017 cropping season. The experiment treatments included phosphorous fertilizer in 4 levels (totally, triple superphosphate fertilizer as base, 70% triple superphosphate fertilizer and the remaining through fertile-2 phosphate biological fertilizer, 40% triple superphosphate fertilizer and the remaining through fertile-2 phosphate biological fertilizer, entirely through fertile-2 phosphate biological fertilizer) and nitrogen fertilizer in 3 levels (entirely through the urea fertilizer, 70% urea fertilizer and the remaining throughazotobacter, 40% urea fertilizer and the remaining through azotobacter). The results showed that the effects of biological and chemical fertilizer phosphorus and nitrogen significantly increased grain weight, seed yield and oil yield. The highest seed yield was for 70% superphosphate fertilizer treatment and the remaining for fertile-2 and 70% urea fertilizer and the rest for azotobacter respectively 3170 and 2736 kilogram in hectare and the lowest one was in the treatment of fertile-2 entirely biological fertilizer and 40% urea along with azotobacter respectively with 2173and 2506 kilogram in hectare. With regard to these results, application of 70% superphosphate fertilizer and the remaining through fertile-2 phosphorous biological fertilizer and 70% urea fertilizer and the rest throughazotobacterrelative to other treatments caused qualitative and quantitative yield increase in sunflower and is recommended in the region.