DefinePK

Abstract

Zinc (Zn) has long been considered as an indispensable micronutrient for crop production and its deficiency is now well established in Pakistani soils. We conducted a field study to evaluate the Zn use relations of five advanced wheat lines, viz. IV-1, IV-2, NARC-2, PAK-13, and V-119 under Zn-deficient soil conditions as affected by the application of 5.0 kg Zn ha⁻¹. The study involved three complete blocks with properly randomized treatments. Application of 5.0 kg Zn ha-1 significantly improved traits such as shoot and root fresh weight (61% and 68%), dry weight (50% and 39%), shoot and root length (77% and 74%), shoot and root Zn concentration (72% and 75%), Zn accumulation (35% and 27%), and Zn-use efficiency (69%). Among the wheat lines, NARC-2 and V-119 demonstrated efficient-responsive characteristics under both Zn-deficient and sufficient conditions. NARC-2 was highly responsive for the biomass production (both shoot and root) and Zn-use efficiency, while V-119 excelled in shoot and root length, Zn concentration, and Zn-use efficiency. IV-3 was the most efficient line under Zn-deficient conditions, showing superior tolerance and a high Zn-efficiency ratio, but was less responsive under sufficient Zn. PAK-13 was highly responsive under sufficient Zn, particularly for Zn-use efficiency, but less effective under deficiency stress. Our findings conclude that zinc nutrition significantly affected biomass production and zinc dynamics of wheat lines at the early growth stage. The NARC-2 and V-119 were found to be the most promising wheat lines for both Zn-deficient and sufficient conditions, with NARC-2 emerging as the most efficient-responsive wheat line. Further research is recommended to validate these findings.