Effect of Integrated Application of Urea and Vermicompost on Qualitative and Quantitative Attributes and Economic Benefit of Potato (Sante cv.) in Behbahan

The aim of this study was to investigate the influence of different nitrogen sources on qualitative and quantitative characters and economic benefit of potato (Sante cultvar). This experiment was conducted in a randomized complete block design with four treatments and three replicates at Behbahan Agriculture Research Station, Behbahan, south-east Iran, in two years (2014 and 2016). Treatments were: 0 nitrogen fertilizer, 50% nitrogen from chemical fertilizer (as urea) + 50% nitrogen from vermicompost (50% M+50%V), 75% nitrogen from chemical fertilizer + 25% nitrogen from vermicompost (75% M+25%V) and 100% nitrogen from chemical fertilizer (100% M). The total and marketable tuber yield, nitrogen use efficiency and agronomic nitrogen use efficiency in 75% M+25%V were significantly higher than the other treatments.  Application of vermicompost in both treatments significantly increased stem and tuber number and decreased tuber nitrate content as compared with 100% M. The effect of vermicompost on tuber dry matter percentage was not significant.  Economic evaluation indicated the highest benefit may be achieved from 75% M+25%V. Supply of 75% required nitrogen fertilizer through vermicompost and 25% nitrogen from mineral fertilizer (as urea) can increase yield and qualitative characters of potato and farmers’ incomes in Behbahan.