The effects of cattle manure and nitrogen fertilizer application on some characteristics of Spinach (Spinacea Oleracea)

In a field experiment, effects of amount different manure and nitrogen were investigated on quantitative and qualitative Spinach (Spinacea Oleracea) characteristics in Agricultural and Natural Resource Research Center of Tehran Province, Iran. Statistical experiment design was conducted with split plot design under randomized complete block design (RCBD), with three replications during two years (2009-2010). Manure (main plot) was considered in four levels of 0, 10, 20, and 30 ton ha-1 and nitrogen (sub plot) was considered in four levels of 0, 150, 200, and 250 kg Nha-1 as urea source. Stems and leaves fresh weight of spinach and there nitrate was measured after harvest. Combined two years results showed that the main effects of manure factor and nitrogen factor were significant on yield, relative yield, water use efficiency, fertilizer use efficiency, agronomic efficiency and nitrate. The interaction effects of manure and nitrogen were significant different only on relative yield, water use efficiency and fertilizer use efficiency. Fertilizer recommendation was 30 ton manure ha-1 with 150 kg N ha-1 for obtaining optimal yield with regard to legal limit of nitrate in spinach plant.