Evaluation of in situ functional activity of casing soils during growth cycle of mushroom (Agaricus bisporus (Lange) Imbach) employing community level physiological profiles (CLPPs).

Community level physiological profiles (CLPPs) have been rarely applied to mushroom compost ecosystem, probably for the lack of standardized methodology. Recently, however CLPPs have been employed as a tool to investigate the degree of maturity of compost (Mondini and Insam, 2005, Compost Science and Utilization, 13(1): 27-33). The potential of CLPPs to detect compost maturity test is considerably significant in that it provides sensitivity and the simplicity of the assay. The aim of this work was to investigate the maturity of casing that comprised of farm yard manure and spent compost and influence of casing type on the behaviour of bacterial community during the growth cycle of mushroom Agaricus bisporus (Lange) Imbach employing standardized inoculum density and effects of different data interpretation based on the kinetics of colour formation. Casing samples of different age were extracted at a particular dilution and then inoculated in 96 well microtitre plates. Optical density (OD) in well was measured at 590 nm every 24 hours for 5 days. Principal component analysis (PCA) was performed by employing OD values at fixed average well colour development (AWCD). PCA of fresh samples showed that classification and ordination of samples according to their age were significant with fixed AWCD.