وایتا فری

In order to investigate the effect of nitrogen fertilizer and foliar spraying of humic acid and Vita free on phenological stages, remobilization indices and yield of sunflower in the second experimental planting in a factorial manner based on a randomized complete block design with with three replications in summer 2018 at Gonbad Kavous University farm research. Cultivar factor was included Haysan 25 and Oscar and combination of fertilizer factor was included no fertilizer application, 100 kg N/ha, 50 kg N/ha, 50 kg N/ha + 1.5 kg humic acid/ha, 50 kg N/ha + 0.5 kg Vita free/ha and 50 kg N/ha + 1.5 kg humic acid + 0.5 kg Vita free/ha. The results showed that the effect of cultivar and fertilizer on most of the measured traits was significant. The results showed that cultivar and fertilizer were significant on most of the studied traits. The maximum days from planting to 50% Flowering, the dry matter of vegetative organs in the flowering stage, the remobilization, current photosynthesis and seed yield were obtained from Oscar cultivar. The maximum remobilization and remobilization efficiency were obtained in the treatment of no fertilizer use. Days from planting to 50% flowering, days from planting to 50% maturity, current photosynthesis and seed yield in 100 kg N/ha treatment and 50 kg N/ha + 1.5 kg humic acid/ha + 0.5 kg Vitafree/h was higher than other fertilizer treatments. Based on results, in order to achieve the maximum seed yield of sunflower and to prevent excessive use of chemical fertilizers, the combined use of Nitrogen fertilizer, humic acid and vita free is necessary.