Fungos associados ao processo de decomposição foliar: 2 anos de estudo

Abstract

The organic matter decomposition process in first order streams is realized mostly by fungi and it is important to provide energy to various trophic levels in this ecosystem. The present work assesses the temporal variation of molds and yeasts, which are collaborators in the leaf decomposition process, in first order stream of Cerrado vegetation in Tocantins State. Plant litter was collected from vertical input of riparian vegetation and inserted in litterbags. Subsequently, they were submerged for 30 days in the Buritizal stream. The isolation and counting of filamentous fungi and yeasts was done from the maceration of leaf discs in peptone solution and streaking in petri disks containing BDA and YMA media for 30 days. The yeasts counting vary from 1,42 logUFC.gMOF in June, 2011 to 5,90 logUFC.gMOF in April, 2012. The filamentous fungi vary from 1,98 logUFC.gMOF in June, 2011 to 6,27 logUFC.gMOF in March, 2013. The highest quantities of fungi and yeasts were observed in rainy periods and they can be due to floods when the drain of the litter or the soil margin happened. As a result, there is a major entrance of terrestrial and saprobic fungi associated in the horizontal input.