Molecular taxonomy as a tool for surveying the plant species diversity in the Cerrado and Pantanal

Abstract

The main goal of this thesis was to show ways of achieving plant biodiversity data using the concept of DNA barcoding, and to analyse the consequences that the lack of DNA barcoding databases has for plant community surveys. In the first chapter, we developed a genomic library of tree and shrub species from an urban cerrado fragment of 36.5 hectares in Campo Grande city, Mato Grosso do Sul state. Furthermore, we have shown ways of using this library for the identification of species and the number of papers published with these species in a phylogenetic context. We were able to cover 31 species for the molecular marker matK and 46 species of trnH-psbA. We have obtained 100% of correct identification through pairwise Blast using matK for 6 of 16 families and 100% of correct identification using trnH-psbA for 4 of 19 families. The second chapter focuses on identifying which of the different plant habits of the Pantanal and which regions of the Pantanal are most represented by molecular markers submitted to GenBank. A total of five molecular markers for 2570 species were searched for availability in the public database. The representativeness was 28.4, 50, 37, 37.2, and 21 for trnH-psbA, ITS, matK, rbcL, and trnL, respectively, intrinsically revealing the gaps in the knowledge of Pantanal plants molecular markers. In the third chapter we have developed a barcoding library of aquatic and terrestrial plants from the Upper Paraguay River Basin in the region of Corumbá, Mato Grosso do Sul, as a tool for plant biodiversity surveys in the face of the enhancement of fire intensity in the past years. We collected a total of 93 species from 75 genus and 35 families, representing a sampling effort of 67% of the number of species described for the area. A total of 52 sequences of trnH-psbA and 41 of ITS were sequenced and deposited in Genbank. We aim to use this genomic library as a reference for surveys that focus on collecting biodiversity data using metagenomics (e.g. environmental DNA). The library is crucial for the identification of sequences obtained in studies of plant biodiversity in the Pantanal to correctly identify the species.