INMIBO ( EX - PROPLAME)   14614
INSTITUTO DE MICOLOGIA Y BOTANICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Impact on soil bacterial communities by herbicides used for Lotus tenuis promotion
Autor/es:
NIEVAS, S; BAILLERES, M; MJ CORRIALE; M.E. LLAMES; A. B. MENENDEZ; O. A. RUIZ
Lugar:
Mar del Plata
Reunión:
Congreso; LI Reunión SAIB 2015. 3 al 6 de Noviembre de 2015, Mar del Plata; 2015
Resumen:
Promoting the forage Lotus tenuis is an appealing alternative to meet the needs for cattle production inthe Flooding Pampa region, Argentina. This agricultural practice requires herbicides application toremove plant species competing with L. tenuis. The use of chemical compounds, in addition to theremoval of native vegetation, eventually may change the diversity of other ecosystem components suchas bacterial communities. The objectives of this work were to examine the effect of L. tenuis promotion onthe bacterial community composition and on specific water-related soil variables, and to detect specificbacterial taxa responding to the L. tenuis promotion. In order to achieve these objectives, here we studiedthree different rangeland sites of the Flooding Pampa region. At each site, two paddocks were compared,one managed to promote the forage legume L. tenuis, and the other lacking of management history andhence, covered by natural grasses. To asses bacterial diversity we used 454-FLX pyrosequencingtechnology of the V4 region of the 16S rRNA gene, on genomic DNA extracted from soil samples. Weobtained 135.918 sequences, representing 3187 Operational Taxonomic Units (OTUs) distributed in 12phyla and 45 classes. Overall, the main identified components of the bacterial community at the Phylumlevel were Acidobacteria, followed by Verrucomicrobia, Planctomycetes and Chloroflexi. Our resultssuggest that 5-6 years of land use with L. tenuis promotion does not affect the microbial communitystructure in this ecosystem. NMDS ordination in two dimensions based on Bray?Curtis distances andPERMANOVA test did not show differences in bacterial community composition between paddockspromoted or not with L. tenuis, although differences among sites were detected. In parallel, Pearson?scorrelation analysis suggested that L. tenuis promotion would indirectly affect members of classesAcidobacteria and Anaerolineae, through altering water-related soil properties.