Zinc Absorption through Leaves and Subsequent Translocation to the Grains of Bread Wheat after Foliar Spray

Agronomic biofortification could possibly be a promising strategy to overcome zinc (Zn) deficiency in wheat; however, the cultivar's response to foliar applications is enigmatic when it comes to the relative efficiency of Zn absorption and accumulation. To decipher that enigmatic response, this study was designed with the objectives (i) to track the amount of Zn absorbed through leaves after foliar application, (ii) to calculate the amount of the absorbed Zn actually translocated and stored in the grains, and (iii) to calculate the relative efficiency of the high yielding cultivars in terms of their Zn absorption and translocation. The results reveal that 0.90% of the zinc sprayed was absorbed through leaves, and 43% of the absorbed Zn was translocated to the grains. The cultivars significantly varied for their Zn absorption (0.71-1.07%) and subsequent translocation of the absorbed Zn (23-66%). Foliar zinc treatment also improved growth attributes such as leaf area, height, spikelet per spike, number of grains per spike, grain yield, leaf and grain Zn content, and grain protein content. These findings suggest a need for cautious parent selection in devising the breeding strategies intended for biofortification.

Automated summary

This study reveals the variations in zinc absorption and translocation among wheat cultivars in response to foliar applications. The results show that zinc absorbed through leaves is mostly translocated to grains, and foliar zinc treatment improves wheat growth and yield traits. These findings provide important guidance for breeding strategies aimed at biofortification.