ROMERO Fernando Matias
congresos y reuniones científicas
Pyrosequencing analysis of rhizospheric and leaf-endophytic bacterial communities of tomato plants
ROMERO FM; MARINA M; MENENDEZ AB; PIECKENSTAIN FL
Congreso; XLVIII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2012
Plant-associated bacteria are of key importance for sustainable agriculture. Bacterial communities associated to tomato plants, and particularly those that colonize leaves as endophytes, are poorly known. Pyrosequencing of the V4 region of the 16S rRNA gene was performed on rhizospheric and leaf-endophytic DNA samples. Tomato plants were grown in a greenhouse in soil collected from an organic tomato plantation and were used to obtain rhizospheric and endophytic DNA. A total of 19,403 and 16,562 sequences were obtained from rhizospheric and endophytic samples, respectively. Based on their similarity, sequences were clustered using UClust, thus obtaining 3,453 total OTUs (Operational Taxonomic Units). Rarefaction curves revealed significant differences in biodiversity between both communities. OTUs abundance was lower in the endophytic than the rhizospheric community. Leaf-endophytic samples saturated at about 80 OTUs while soil samples increased over 1,700 OTUs. Endophytic communities were represented mainly by unknown bacteria, while among classified bacteria, Gammaproteobacteria was the main group. Almost 45% of the rhizospheric communities was represented by Verrumicrobia and Acidobacteria. These results demonstrate that a relatively small group of rhizospheric bacteria is able to colonize plant leaves as endophytes, the majority of which are unknown.