To boost agricultural yields, understanding mineral nutrition's reliance on fertilizers is crucial, underscoring the need to evaluate nutrient-use efficiency for optimal fertilization. In this regard, a field study was conducted to elaborate the role of phosphorus fertilizer in enhancing growth, yield and marginal rate of return in four wheat varieties; two Zn-biofortified (Zincol-2016 and Akbar-2019) and two standard types (Anaj-2017 and FSD-2008). The study revealed that application of phosphorus significantly enhanced the uptake of nitrogen (N), phosphorous (P) and potassium (K) contents in straw (13%, 59% and 79%) and grains (63%, 92% and 28%) respectively. Similarly, the contents of Zinc (Zn) and iron (Fe) were reduced in straw (23% and 19%) and grains (19% and 18%) respectively after application of 80 and 120 kg P2O5, however at 40 kg P2O5 the contents of Zn and Fe were slightly enhanced. The grain yield (21 %) and harvest index (11 %) was maximum at 80 kg P2O5 as compared to 40 and 120 kg P2O5. The Marginal rate of return over investment (MRR) in P2O5 was maximum (241%) in Akbar-2019 when P-fertilizer was applied at the rate of 80 kg P2O5 per ha(-1). Regression analysis showed a positive correlation between grain yield and its determinants. Biofortified wheat varieties responded better to 80 kg P2O5, outperforming standard varieties in yield. Additionally, our findings demonstrate a significant upregulation of PSTOL1 gene expression at 80 kg P2O5 level. Concludingly the application of P-fertilizer at the rate of 80 kg P2O5 per ha(-1) enhanced growth, yield and rate of return of testing wheat varieties especially the biofortified ones; Zincol-2016 and Akbar-2019.