Improving Wheat Grain Quality Through Zn, Cytokinin and Gibberellic Acid Applications

The low concentration of zinc (Zn) in cereal crops is primarily caused by Zn-deficient soils and poor transportation from the source to sink. The study examined the impact of Zn, cytokinin and gibberellic acid (GA) on wheat Zn content, grain protein and grain phytic acid content. The experimental design was split-split plot with three replications. The main plots consisted of two varieties, namely V1 (PBW 725) and V2 (PBW 752), which were subsequently splitted into three subplots: Zn0 (no Zn application), Zn1 (62.5 kg ha⁻¹soil application of ZnSO_4.7H₂O) and Zn2 (31.25 kg ha⁻¹ Zn application in soil + foliar spray of 0.5% ZnSO_4.7H₂O). The subplots were subdivided into four sub-sub plots, namely H0 (no hormone), H1 (10 mg L⁻¹ GA), H2 (10 mg L⁻¹ cytokinin) and H3 (5 mg L⁻¹ GA + 5 mg L⁻¹ cytokinin).The results indicated that the combination of Zn2 + H1 resulted in maximum stem and leaf Zn content in both varieties. The reported increment in Zn content of both the plant parts was 30.30% and 37.49% for V1 and 36.7% and 38.18% for V2, respectively. However, for both V1 and V2, the combination of Zn2 + H2 improved grain Zn content by 25.79% and 26.57% respectively. Similarly, the same combination increased grain protein content in V1 and V2 by 18.41% and 16.24% respectively. Regarding phytic acid content in grains of both V1 and V2, a reduction was reported under the combination Zn2 + H2 than Zn0 + H0 and the reduction was 48.32% in V1 and 48.19% in V2. Overall, the study highlighted the soil + foliar application of Zn along with 10 mg L⁻¹ cytokinin had the greatest impact on enhancing Zn and protein content in grains while decreasing phytic acid in grains of both wheat varieties.