The antagonistic bacterium, Pantoea agglomerans HR, was evaluated for controlling citrus green mould caused by Penicillium digitatum Sacc. at 20°C (room temperature) and 4°C (cold storage). This isolate was also assessed in combination with dipping in 3% sodium bicarbonate solution at 24°C and 45°C on artificially inoculated Thomson navel oranges. Application of the antagonist alone reduced green mould by more than 75% at both temperatures, but was not as effective as Imazalil (more than 87% decay reduction). The antagonistic bacterium was completely tolerant to sodium bicarbonate up to a concentration of 3%. In addition, its efficacy for controlling green mould was improved at least by 5% and 11% when combined with 3% sodium bicarbonate at 24°C and 45°C, respectively.