Mollifying Salt Depression on Anethum graveolens L. by the Foliar Prescription of Nano-Zn, KNO3, Methanol, and Graphene Oxide

Abstract

The aim of the study was to assay the salinity impacts on Anethum graveolens by the foliar application of nano-Zn, KNO3, methanol, and graphene oxide in hope to mitigate the stressor side effects. NaCl salinity (0, 50, and 100 mM) and foliar spray with graphene oxide, methanol, KNO3, and nano-zinc were examined to evaluate the growth and physiological responses, antioxidant enzyme activity, and the essential oil content and constituents of Anethum graveolens. The results revealed that salinity × foliar combinations significantly affected N, P, and Na content of plants. The top recorded data for K+/Na+, catalase activity, and chlorophyll a content belonged to control plants. Control and 50-mM salinity treatments attained the highest aerial part dry weights, total chlorophylls, and essential oil yield. One hundred-millimolar salinity induced the greatest malondialdehyde, H2O2, and proline content. Foliar treatment of methanol, KNO3, and nano-zinc added up K+ content. GC/MS analysis revealed the occurrence of 21 constituents in the oil. Dill-apiol (24.06–88.5%) was the major constituent; NaCl100mM× methanol treatment attained the highest dill-apiol content. In conclusion, Anethum graveolens was tolerable to 50-mM salinity without remarkable loss in the growth characteristics and yield. Moreover, foliar treatment of KNO3 and nano-zinc partially ameliorated the adverse side effects of salinity.