Study of fungi associated with decomposition of rice stubble and their role in degradation of lignin and holocellulose

Twenty-seven species belonging to 15 genera (excluding one unidentified fungus) were isolated from decomposing rice stubble by dilution plate technique. The highest number of colonies (1166 cfu/g of rice stubble) was recorded in 45 days-old stubble and lowest (525) in 30 days-old stubble. Twelve dominant fungi capable of degradation of rice stubble, especially lignin and holocellulose, were tested for decomposition of rice stubble at three incubation periods (20, 40, 60 days). The study revealed a positive correlation between species inoculated and loss in dry weight of stubble with respect to different incubation periods. Highest loss in dry weight was recorded after 60 days of incubation. Penicillium citrinum showed the highest lignin degrading ability while Aspergillus flavus proved to be the most efficient degrader of holocellulose. All experiments were validated through ANOVA test.