In the present study, Rhodopseudomonas palustris a proteolytic purple non sulphur bacterium was used as biofertiliser and its effect on the root and shoot lengths of four plants have been investigated. To study its potential as biofertiliser, it was primarily screened by seed germination and roots and shoot length growth. In our study, we have observed significant change in the growth of Oryza sativa, Solanum lycopersicum, Coriandrum sativum and Trigonella foenum. On inoculation of nitrogen and photosynthetic bacterium, the rice HMT variety was observed to be more responsive compared to Poojalu variety. Increased shoot length was found in both the varieties. Even in the plants like Solanum lycopersicum, Coriandrum sativum and Trigonella foenum the rate of growth is more when the photosynthetic bacterium was inoculated. The role of Nitrogen on the growth of leaves, roots, stem and vegetative parts of plants is seen in this work. Nitrate contaminations in ground water, eutrophication of aquatic ecosystems etc. are some of the environmental hazards occurring due to excess amounts of chemical fertilizers (Carpenter, 2005; Diaz and Rosenberg, 2008). This paper also includes the study of Eldin and Elbanna (2010) demonstration of the beneficial effects of another purple non sulphur bacteria namely Rhodobacter capsulatus. They concluded that these bacteria enhanced the growth and yield of rice in both pots and lysimeter. It was, also concluded the use of old seeds leads to high rate of growth promotions. The increase in height and dry weight of the roots and stem by Rhodopseudomonas palustris and Nitrogen is seen initially. The growth is more when both the Nitrogen and bacteria are used in the cultivation.