The effect of slow release urea containing hydrogel complex on yield, yield components and physiological traits of barley under water deficit stress

In order to study the effect of slow release hydrogel-urea complex (SRHUC) on yield, yield components and physiological traits of barley under water deficit, an experiment was performed in 2017-2018 and conducted as factorial in Randomized Complete Block Design (RCBD) in three replications in greenhouse of Aburaihan campus of University of Tehran. The combination of factorial levels were as fertilization factor containing nitrogen (N) from urea source in five levels of no use of N, equivalent 125 and 65 kg.ha-1 N (without SRHUC) as CU-N125 and CU-N65 and equivalent 125 and 65 kg.ha-1 N with SRHUC as SRHUC-N125 and SRHUC-N65 and water deficit in three levels of 70, 50 and 30% of FC. Water deficit decreased yield and yield components, RWC and SPAD. The highest grain yield in a pot belonged to SRHUC-N125 (41.9 g) and there was no significant difference between CU-N125 (41.5 g) and SRHUC-N65 (39.1 g). For most of the traits, there was no significant difference between SRHUC-N125 and SRHUC-N65 and CU-N125. Under stress, utilization of SRHUC for both N amount could generate a better biological yield and SPAD index. Using N in the form of SRHUC was preferred to using of N without SRHUC, especially under stressed conditions.