In order to study the effect of foliar spray of microelement fertilizers Fe, Zn and Cu on yield and yield components of durum wheat (cv. Dehdasht) an experiment was conducted as strip split plots in randomized completely block design with 3 replications. Treatments were spraying time as main factor (at two levels including 2 weeks before flowering and 50% flowering) and microelement fertilizer as subfactor (at 8 levels including N1=Fe, N2=Zn, N3=Cu, N4=Fe+Zn, N5=Fe+Cu, N6=Zn+Cu, N7=Fe+Zn+Cu and N8= no spraying). Analysis of variance showed that spraying time was significant only for test weight at 5% level. However, fertilizer effects were significant for most of studied traits. Means comparison revealed that all fertilizer treatments imposed positive effects on spike length and kernel protein content, but Zn had highest positive effect on them (13.4% and 9.6% compared to check, respectively). All fertilizer treatments imposed positive effects on test weight, but Cu had highest positive effect on it (6.1% compared to check). Also, all fertilizer treatments imposed positive effects on economic yield, but Fe+Cu had highest positive effect on it (34.1% compared to check). Although all fertilizer treatments imposed positive effects on fertile tiller number, but Cu+Zn had highest positive effect on it (61.6% compared to check). This treatment, also, had highest positive effect on 1000-kernel weight and spike number per unit area, and highest negative effect on sterile floret number (9.2, 17.3 and -18% compared to check, respectively). Fe+Cu+Zn treatment had highest positive effect on plant height, fertile floret number and kernel number per spike (15.1, 17.6 and 14.3% compared to check, respectively). If only one micronutrient was to be utilized, Zn is obviously the best choice for improvement of yield and its components. Since all fertilizer treatments had positive effects on most of important traits, it can be suggested the utilization of Fe+Zn+Cu treatment in the form of foliar spray in culture of durum wheat
