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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
It is well-known that Nilgiri forest biosphere in India contains high microbial biodiversity of bacteria, fungi, actinomycetes and nematodes that play an important role in the ecosystem. The present investigation was carried out in the Nilgiri forest ecosystem in the division of North nilgiris, Tamil Nadu, India during 2017-2020 to evaluate the microbial diversity of undisturbed forest soil in two different altitudes viz., Kallar and Ooty with comparison of agro-ecosystem and polluted ecosystem and in four different seasons viz., summer (S1), pre-rainy (S2), post rainy (S3) and winter (S4). Representative soil samples were collected at four different depths (0-15, 15-30, 30-45 and 45-60 cm) during four different seasons (summer, pre-rainy, post-rainy and winter) from all the ecosystem areas of Nilgiri forest ecosystem and were analysed for their availability for population dynamics. Samples taken during post rainy season recorded highest fungal population of 178 x 105 CFU/g/soil in the kallar forest ecosystem as compared to the polluted ecosystem and lowest population for bacteria and actinomycetes. The major bacterial genera found in diversity study are occupied by Bacillus and Pseudomonas, which can survive in high temperature (75 x105 CFU/g/soil) in summer season. Most of the population (>75 x105 CFU/g/soil) of fungal genera were found in low temperature and high relative humidity in Post rainy and winter season (Acrostalagmus, Polyporus, Phelliinus, Trichoderma, Aspergillus spp., Alternaria). In one gram of soil, population of bacterial feeding nematodes (Rhabditis sp. and Acrobeles sp.) dominated in lower altitudes of Kallar which resulted in higher rate of decomposition. Fungal feeding nematodes (Aphelenchus sp and Aphelenchoides sp.) were more in higher altitudes with soil having acidic pH due to leaching effect favored the growth of fungus. The conclusion drawn from the present study showed an increase in fungal population and fungal feeding nematode population at higher altitudes and reduction in bacterial and actinomycetes population in all the four ecosystems and all the microbial population were highest in post rainy seasons when compared to pre-rainy, summer and winter seasons.