Effect of Foliar and Soil Application of Zinc on Grain Weight and Some Biochemical Traits of Wheat (Triticum aestivum L.) under Salinity Stress

In order to study the effect of foliar and soil application of Zinc on grain weight and some biochemical traits of wheat (Triticum aestivum L.) under soil salinity, an experiment has been conducted as factorial based on randomized complete block design with three replications in research greenhouse of University of Mohaghegh Ardabili in 2018-2019. Experimental factors include soil salinity levels [control and salinity of 30, 60, and 90 mM] and four methods of zinc application [no zinc as control, soil application zinc as ZnSO4, foliar application nano zinc oxide, and combination of soil and foliar application of zinc]. Results show that both application of ZnSo4 and foliar application nano Zn oxide under 90 mM soil salinity condition increase the catalase and peroxidase enzymes activity, anthocyanin, proline, and soluble sugars content by 20.24%, 17.68%, 13.16%, 32.88%, and 14.08%, respectively, in comparison with no application of zinc under 90 mM soil salinity condition. Also, both soil application of ZnSo4 and foliar application of nano Zn oxide under non-salinity condition decrease hydrogen peroxide and malondialdehyde content in comparison with no application of Zinc under 90 mM soil salinity. Both soil application ZnSo4 and foliar application nano Zn oxide under non-salinity condition has had the highest grain weight (1.016 g per plant), compared to the application of this treatment combination at other salinity levels. It seems that both application of ZnSo4 and nano Zn oxide can increase weight yield of wheat under salinity condition due to their ability in improving biochemical traits.