MICROBIAL METADATA INTEGRATION IN SUGARCAME SOIL SYSTEMS

Abstract

This proposal intend to integrate the chemical, physical and microbiological analysis of sugar cane cultivated soil under two different managements: residue systems harvesting (mechanized) and burning harvesting (manual), both obtained in growing areas that adopt these crop production systems in the state of São Paulo (Brazil). To aim this objective, it will be considered recent methodologies in molecular biology area (large scale sequencing) and bioinformatics (artificial interaction networks analyses). The changes of microbial communities in soil, associated with the biogeochemical cycles of carbon (C) and nitrogen (N) will be monitored using the DNA microarray technique to determine the functional activities in both harvesting systems of sugar cane, previously mentioned. To validate this technique it will be encompassed field and greenhouse data, to be applied in successive years of sugar cane without burning (5, 10 and 15 years) and burning sugar cane. The monitoring of biogeochemical processes of C and N in soils under sugar cane through the microbiota associated with N (N2 fixation, ammonification, nitrification, denitrification) and C (organic matter decomposition and methane and CO2 absorption) will allow the application of connectionist models based on artificial interrelations networks for the integration of molecular data obtained in large-scale with physical and chemical soil parameters, aiming responses of soil microbial communities analysis. Such models would be supported by bioinformatics knowledge recently applied to soil science and, in particular, soil microbiology. These models will be separated into four main modules: (i) "microbial community", contemplating taxonomic data of the domain Bacteria obtained from large scale by Molecular methods (large scale sequencing, qPCR and microarray), (ii) "metagenomics functional" closing action of genetic diversity of functional groups involved bacterial biogeochemical cycles of C and N (data from large scale sequencing and qPCR); (iii) "soil", using physical and chemical soil parameters, and (iv) "temporality" encompassing analysis in sugar cane without burning in the period of 5, 10 and 15 years, in traditional sugar cane area, pioneered in the adoption of the conservationist system. In this proposal it will be used approaches on large scale sequencing, quantitative real time PCR (qPCR) and the development of microarray technique, which will enable the assessment and monitoring of possible microbial groups that could be considerate soil bio-indicators. It is expected that this work provide information for understanding the taxonomic and functional aspects (modules "microbial community" and "functional metagenomics") to respond to different management culture of cane sugar harvesting, that are directly related to biogeochemical cycles of C and N.