Response of spinach (Spinacia oleracea) yield and nutrient uptake to urea and manure

Abstract

This experiment was conducted in 2007 at the Agriculture Research Center, Shahrud, Iran, to evaluate the effect of urea and manure on spinach yield, nutrient uptake and nitrate accumulation. The experiment was conducted in split plot in the form of a randomized complete block design with three replications. Treatments of the experiment were manure (0, M0; 25, M1; 45, M2; ton/ha) and urea (0, U0; 100, U1; 200, U2; 300, U3; kg/ha). At the harvest time two samples were taken from each treatment: one in the morning (7-8 am) and another in the evening (6-7 pm). Results indicated that higher urea and manure application rates increased yield; the interaction of 300 kg urea/ha × 45 ton manure/ha increased yield by about 54% compared with the control. Moreover, nitrate accumulation was higher in samples taken in the morning compared with those taken in the evening. © Indian Society for Education and Environment (iSee).