Phosphorus (P) is an essential nutrient, required for the normal growth and development of plants. Adequate P nutrition plays very significant role in developing efficient root system of plants, especially under P deficiency stress. This field study reports the beneficial effects of adequate P nutrition and biopriming of mustard seed with ACC-deaminase, phosphate-solubuilizing rhizobacteria (Pseudomonas fluorescens) on mustard root architecture and P accumulation of mustard plants and consequently on mustard yield.