V. Manimegalai, V. Ambikapathy and A. Panneerselvam
Soil contains many kinds of microorganisms. It is the loose mineral material on the surface of earth.Soil is a very good culture medium for the growth of microorganisms. This study deals with the fungal diversity at four sites of traditional paddy field in Thanjavur district, TamilNadu. The study period was one year covering all the four seasons viz, premonsoon (January and February), Summer (March to May), Monsoon (June to September), postmonsoon (October to December). About 30 different species belonging to Ascomycetes and Phycomycetes and most of them belonged to Deuteromycetes were isolated by using PDA medium and identified with standard Manuals. During monsoon season maximum fungal count was recorded in 2009- 2010.The dominant species isolated were Aspergillus niger , A. flavus, A. clavatus ,Curvularia lunata, Bipolaris oryzae, Penicillium janthinellum, P. citrinum followed by Rhizopus nigricans, Trichoderma viride and T. harzianum from the paddy field soil of Vallam in various seasons whereas, in Marungulam soil A. niger, A. fumigatus, A. terreus, Bipolaris oryzae,T. harzianum, T. viride, P. janthinellum, F. oxysporum and Rhizopus nigricans were recorded. In Nanjikottai soil A. niger, A. fumigatus, B. oryzae, P. janthinellum, T. harzianum was recorded. In Vadakupattu soil the dominant species recorded were A. niger, B. oryzae, P. janthinellum, T. harzinaum, T. viride, P. citrinum respectively. This study deals with the seasonal variation in soil fungal population in relation to the soil nutrient variability by correlated between fungal population and physico- chemical parameters to comparable levels of fungal richness were observed.
