Microbial counts of dark red latosol samples stored at different temperatures

RESUMO

The number of colony forming units (CFU) of different groups of bacteria and fungi in samples stored at temperatures of 5 to -12§C for 0-32 weeks was evaluated. The number of CFU obtained after the different periods of storage of red latossol soil was compared with the number of colonies obtained immediately after removal of soil samples (time zero). The number of total bacteria and actinomycetes in the samples remained pratically unchanged throughout the storage period. The number of Gram-negative bacteria decreased by as much as 69 per cent compared to control, while the number of Bacillus spp and of fungi increased 1.9 to 4.9 times starting from the 12th week in sample stored at 5§C. Except for the variations observed in fungal counts, the remaining groups of bacteria pratically showed the same variation in number of colonies in soil samples stored at 5§C and -12§.