Phosphate-solubilising ability and co-production of plant growth promoting traits of stress tolerant Bacillus subtilis CB8A isolated from apple rhizosphere was tested under in vitro conditions against a wide range of temperature (30–45°C), pH (7–9) and salt (0–5%) stresses. Under the extremes of temperature (45°C), pH-9 and salt concentration (5%), production of soluble phosphate, indole acetic acid, siderophore and antifungal activity against Dematophora necatrix were reduced by 71.09%, 75.29%, 90.3% and 88.47%, respectively. Per cent decrease in P-solubilisation at extreme temperature (45°C) and normal pH (7) without salt concentration was 36.23%; at extreme pH (9) and normal temperature (37°C) without salt concentration was 23.45% and at extreme salt concentration (5%), optimum temperature (37°C) and pH (7) was 36.7%. P-solubilisation by CB8A was inversely correlated with pH (r = −0.78) and positively correlated with siderophore production (r = 0.81), indole acetic acid (r = 0.58) and antifungal activity (r = 0.63). Gluconic acid (1.43%) and citric acid (0.67%) were detected as major organic acids. P-solubilisation and nitrogen fixing abilities of B. subtilis CB8A were confirmed by amplification of gdh and nifH genes. The ability of CB8A showing plant growth promoting rhizobacteria (PGPR) traits at a wide range of temperature, pH and varying salt concentration can be exploited for developing multifunctional biofertiliser in apple orchards.