ORIGINAL PAPER Effect of bioaugmentation and nitrogen supplementation on composting of paddy straw Alok Kumar Pandey Æ Sunita Gaind Æ Arif Ali Æ Lata Nain Received: 3 April 2008 / Accepted: 12 September 2008 / Published online: 4 October 2008 Ó Springer Science+Business Media B.V. 2008 Abstract A composting experiment was conducted to evaluate the effect of a hyperlignocellulolytic fungal consortium and different nitrogen amendments on paddy straw composting in terms of changes in physicochemical and biological parameters. A fungal consortium comprising four lignocellulolytic meso- philic fungal cultures was used as inoculum for bioaugmentation of paddy straw in perforated pits. The comparative effect of farmyard manure (FYM), soybean trash, poultry litter and urea on the com- posting process was evaluated at monthly intervals in terms of physicochemical (pH, EC, available P, C:N ratio and humus content) and biological (enzymatic and microbial activity) parameters. The compost prepared from bioaugmented paddy straw compost- ing mixture, with poultry manure as nitrogen supplement attained desirable C:N ratio in 1 month and displayed least phytotoxicity levels along with higher production of b-1,4-Exoglucanase. The com- bined activity of the autochthonous composting microbiota as well as the externally applied fungal inoculum accelerated the composting process of paddy straw. Supplementation of paddy straw with poultry manure in 8:1 ratio was identified as the best treatment to hasten the composting process. This study highlights the importance of application of fungal inoculum and an appropriate N-amendment such as poultry manure for preparation of compost using a substrate having high C:N ratio, such as paddy straw. Keywords Composting Á Bioaugmentation Á Farmyard manure Á Poultry manure Introduction In the current scenario, agricultural waste manage- ment is an important issue worldwide. Crop residues, especially cereal straw which are somewhat recalci- trant, need to be managed tactfully so that the soil organic matter resulting from their bioconversion gives maximum possible benefit to soil health. Paddy straw, one of the most recalcitrant materials among cereals, is not suitable as animal feed because of its high silica content (Juliano 1985). Also, it is burnt in various parts of the globe because of its slow degradation rate in nature. Such practices lead to wastage of large chunks of this otherwise valuable natural resource. Although direct transformation of crop wastes in fields is an alternative for their cost- effective utilization, soil application of large doses of A. K. Pandey Á S. Gaind Á L. Nain (&) Division of Microbiology, Indian Agricultural Research Institute, New Delhi 110 012, India e-mail: latarajat@yahoo.co.in; latarajat@rediffmail.com A. Ali Department of Biosciences, Jamia Millia Islamia, New Delhi, India 123 Biodegradation (2009) 20:293–306 DOI 10.1007/s10532-008-9221-3