Rice has been considered as the staple food of majority of the population of Asia. Soil and irrigating water quality around the globe are deteriorating day by day; hence it is necessary to understand the response of rice crops towards these environmental abuses. The present study was carried out on unique type of rice variety (Pokkali VTL-4) cultivated in acid saline soils of Kerala. Oryza sativa (Pokkali VTL-4) plants were cultivated under different boron, proline and NaCl concentration, in order to study their response mechanism under various environmental stresses. There was a considerable decrease in plant boron concentrations after 14 days of proline treatment. Also, reasonable decrease in plant Boron concentration was observed after 7 days of proline treatment. The effect of salinity and boron toxicity on the proline metabolism was also studied by estimating the enzyme Pyroline-5-Carboxylate Synthatase (P5CS). The enzyme P5CS catalyses the first step in the pathway of conversion of glutamate to proline (Glutamate pathway). The enzyme assay indicated that, the P5CS activity increased under low boron and NaCl concentration. There was a considerable decrease in P5CS activity under high boron and NaCl concentration. Hence, the results showed that proline synthesis occurs by Glutamate pathway under less stress condition and by Ornithine pathway under severe stress condition.