effect of different n fertilizer combinations and irrigation regimes on concentration, uptake and efficiency of major nutrients in plantago ovata

in order to evaluate the response of major nutrients concentration, uptake and their efficiencies of isabgol (plantago ovata) to n fertilizer combinations and irrigation regimes, a field experiment was conducted at the agricultural research farm of shahrekord university, 2009. the experiment was arranged as split-plot, in randomized complete block design with three replications. the irrigation regimes (irrigation after 7, 14 and 21 days interval) were arranged as main plots and combination of different n fertilizers included control, urea fertilizer (uf), broiler litter  (bl), uf+bl (3:1), uf+bl (1:1), uf+bl (1:3) as subplots. results showed that the highest shoot dry weight and n uptake were achieved with 7 and 14 days irrigation regimes, respectively. there was no significant difference between 7 and 14 days irrigation regimes for shoot dry weight and n uptake. the greatest nae, pae and ppe were obtained with 14 days irrigation regimes. the highest shoot dry weight, n uptake, nae, anr and pae were observed with uf+bl (1:1) as well as. uf+bl treatment led to increase nae, anr, pae greater than solitary application of them. in conclusion, increase in n and p efficiency and dry matter associated with combined treatment (uf+bl, 1:1) would help to minimize the use of synthetic mineral fertilizers and represents an environmentally and agronomically sound management strategy.