Among the treatments, weedy and butachlor plots had higher population of weeds. Weed population was lower at all the doses of rice straw incorporated with the lowest in 500 g/m2 rice straw treatment. Data on weed dry weight recorded at 60 DAT revealed a significant decrease in all the plots where rice straw was incorporated as compared to weedy and butachlor treated plots. Grain yield was also higher at all the doses of rice straw incorporation while it was lowest (2658 kg/ha) in the weedy treatment (Table 3). Highest grain yield (3,925 kg/ha) was obtained, irrespective of cultivars, in the treatment with the highest rice straw incorporation (500 g/m2). A total of 17 compounds were recorded in the straw. Among these, four compounds could be identified after comparing with phenolic standards. These were gallic acid, phydroxy benzoic acid, ferulic acid and vanillic acid.