Nano-fertilizers in agriculture are becoming prevalent because of the unique and outstanding properties of these materials. Bimetallic nanoparticles can simultaneously provide essential elements for plants. A field experiment was conducted on a semi-arid region at Maragheh, northwest of Iran to study effects of foliar application of Fe3O4 nanoparticles (Fe-NPs), ZnO nanoparticles (Zn-NPs), mixed monometallic Fe3O4 + ZnO nanoparticles, bimetallic Fe-Zn nanoparticles and distilled water (as control) on biochemical attributes of two chickpea cultivars (Gogso and local). The tallest plant was recorded for cv. Gogso by application and Zn-NPs and Fe3O4+ ZnO nanoparticles. Evaluation of seed yield component such as 100-seed weight, pod and seed number per plant showed that foliar spry of bimetallic Fe-Zn nanoparticles significantly increased the agro-economic performance especially in cv. Gogso. Assessment of leaf chlorophyll a, b and carotenoids content showed that although the additive effect of Fe-NPs was greater than the Zn-NPs, the highest pigments content was recorded for cv. Gogso by utilization of bimetallic Fe-Zn. Also, antioxidant enzymes such as ascorbate peroxidase (APX), catalase (CAT), superoxide dismutase (SOD) and guaiacol-peroxidase (GPX) significantly induced by application of micronutrients and highest activity was recorded for prayed by bimetallic Fe–Zn. This was confirmed by a significant reduction in hydrogen peroxide (H2O2) concentration. Our results showed that cv. Gogso was more responsive to composite micronutrient nanoparticles than local cultivar. This highlights that the bimetallic Fe-Zn nanoparticles improves plant physiological properties, seed yield, and its utilization is therefore especially beneficial for progressive nano-fertilizer industries.
