Effect of Nitrogen and Phosphorus Fertilizer Rates on Growth, Yield and Yield Components of Sun Flower Varieties

The experiment was carried out for two successive years (2017 and 2018) at to evaluate the effect of different levels of phosphorus and nitrogen fertilizer application on yield and yield components of sunflower. One released variety Oissa and two pipe lines Adadi- 1 and NK ferti; five fertilizer rates (F1= No fertilizer, F2= 11.5 kg N/ha & 11.5 P2O5 kg/ha, F3= 23 kg N/ha & 23 kg P 2 O 5 /ha), F4= 34.5 kg N/ha & 34.5 kg P 2 O 5 /ha and F5= 46 kg N/ha & 46 kg P 2 O 5 /ha ) were arranged in RCBD with factorial combination and three replication. The main effect of fertilizer rate significantly affected all yield and yield related traits except seed oil content at both locations. Oissa have almost the same seed yield response both sites with an average seed yield of 1653kg/ha and 1641 kg/ha respectively. The partial analysis result showed out of the five tasted fertilizer rates application of 34.5 kg N/ha and 34.5 kg P 2 O 5 /ha becomes profitable than others and can be recommended for sun flower production. This preferable fertilizer rate record high net benefit for all varieties but it needs a variety preference for locations. Using the same fertilizer rate, Adadi 1 and 'Nk fert' varieties gave high seed yield at Adadi than Holetta sites. Keywords: sunflower, variety, fertilizer rate, seed yield, seed oil DOI: 10.7176/JNSR/11-15-05 Publication date: August 31 st 2020