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Nitrous oxide (N2O) emissions from Vertisols and Alfisols during sweet sorghum cultivation in the Indian semi-arid tropics were determined using a closed chamber technique during the rainy season (June-October) of 2010. The study included two treatments, nitrogen (N) at a rate of 90 kg/ha and a control without N fertilizer application. The N2O emissions strongly coincided with N fertilization and rainfall events. The cumulative N2O-N emission from Alfisols was 1.81 N2O-N kg/ha for 90 N treatment and 0.15 N2O-N kg/ha for the ON treatment. Similarly, the N2O-N emission from Vertisols was 0.70 N2O-N kg/ha for 90 N treatment and 0.09 N2O-N kg/ha for the 0 N treatment. The mean N2O-N emission factor for fertilizer induced emissions from the Alfisols was 0.90% as compared to 0.32% for Vertisols. Our results suggest that the N2O emissions are dependent on the soil properties. Therefore, the monitoring of N2O emissions from different agro-ecological regions, having different soil types, rainfall characteristics, cropping systems and crop management practices are necessary to develop comprehensive and accurate green house gas inventories. (C) 2012 Elsevier B.V. All rights reserved.