Comparative effects of conventional and nano-enabled fertilizers on morphological and physiological attributes of Caesalpinia bonducella plants

To increase the agricultural production, nano fertilizers have allowed the development of new technologies. In this study, zinc oxide nanoparticles (ZnO-NPs), iron oxide nanoparticles (FeO-NPs) and magnesium oxide nanoparticles (MgO-NPs) have been prepared and applied on the medicinal plants (Caesalpinia bonducella) to increase the yield, nutrient and chlorophyll contents. This study intended to compare the impacts of synthesised NPs with the control plants and their conventional fertilizers such as ZnSO4·7H2O (Zn-bulk), FeSO4·7H2O (Fe-bulk) and MgSO4·7H2O (Mg-bulk). All fertilizers were applied in a completely randomized design including six treatments and three replications of each treatment by using a combination of seed priming method and soil mixing process. Moreover, the NPs were also compared for the best gaining of results. The concentrations selected for applications were 10, 20, 30, 40 ppm for iron and magnesium fertilizers and 25, 50, 75, 100 ppm for zinc-based fertilizers. The results indicated the increase in morphological parameters of the plants of 28–50% by the application of conventional fertilizers while 50–93% by NPs application as compared to control plants. Furthermore, the increase in chlorophyll contents was 5–28% with conventional fertilizers while 30–80% in case of NPs application than control plants. The obtained results indicate that the best increase in growth, nutrient and chlorophyll contents of plants were achieved at the dose concentrations of 40 ppm for Mg and Fe fertilizers and 100 ppm for Zn fertilizers. The comparative study of NPs showed that the highest growth and yield was obtained by the use of ZnO-NPs in comparison to others. Finally, it is worth highlighting that NPs have a huge potential to increase the productivity of crops if applied in optimal concentrations.