Taxonomic and functional microbial bio-indicators in soil under sugarcane biomass production systems

Abstract

Defining and monitoring soil quality parameters is key to sustainable primary of raw materials for bio-based industrial processes. In this sense, new methods based on DNA sequencing in association to traditional methods can cooperate to define biologically relevant assay to judge the potential impacts from the production processes on soil health. Recent results generated by Capes/Wageningen program (Navarrete et al., 2012) showed members of soil bacterial community belonging to the phyla Acidobacteria and Verrucomicrobia (at class taxonomic level) and genes encompassing the biogeochemical cycle of carbon as potential bio-indicators for deforestation effects on soil and agriculture management into soybean production fields in the State of Mato Grosso, Brazil. In this sense, this proposal aims to validate these results in a broder Brazilian agricultural context, by attesting the microbial bio-indicators for assessment of soil quality in sugarcane biomass production systems in the State of São Paulo. To this end, the objective of this project is to validate bacterial taxa (Acidobacteria and Verrucomicrobia) and identify bacterial groups and functional genes with potential use as taxonomical and functional bio-indicators and associate them to soil characteristics and processes occurring in soil, such as, fertility, nutrients availability, microbial biomass, enzyme activity and N2O, CO2 and CH4 emissions from soil in sugarcane biomass production systems in the State of São Paulo. Three different modules compose the activities plan: (i) "taxonomic bio-indicators", including abundance determination of Acidobacteria and Verrucomicrobia and also other bacterial groups in soil by sequencing partial of the 16S rRNA gene using next-generation technologies (pyrosequencing) and statistical correlation with soil physico-chemical attributes; (ii) "functional bio-indicators", including quantitative and comparative analysis of metagenomic data (shotgun MiSeq) in association to soil physical, chemical, biological and biochemical attributes and N2O, CO2 and CH4 emissions from soil; and (iii) "bioinformatic ans statistic", including computational and statistical approach to integrate results from modules "i" and "ii", aiming ensure the indication of taxonomical and functional bio-indicators for soil quality assessment in sugarcane biomass production systems.