Herbicide- mediated promotion of Lotus tenuis (Waldst. & Kit. ex Wild) did not influence soil bacterial communities, in soils of the Flooding Pampa, Argentina

NIEVA, AMIRA SUSANA; BAILLERES, MATÍAS; CORRIALE, MARIA JOSE; LLAMES, MARIA EUGENIA; MENENDEZ, ANA; RUIZ, OSCAR

APPLIED SOIL ECOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 98 p. 83 - 91

0929-1393

Promotingthe forage Lotus tenuis is an appealing alternative to meet the needs forcattle production in the Flooding Pampa region, Argentina. This agriculturalpractice requires herbicides application to remove plant species competing withL. tenuis. The use of chemical compounds, in addition to the removal of nativevegetation, eventually may change the diversity of other ecosystem componentssuch as bacterial communities. The objectives of this work were to examine theeffect of L. tenuis promotion on the bacterial community composition and onspecific water-related soil variables, and to detect specific bacterial taxaresponding to the L. tenuis promotion. In order to achieve these objectives,here we studied three different rangeland sites of the Flooding Pampa region.At each site, two paddocks were compared, one managed to promote the foragelegume L. tenuis, and the other lacking of management history and hence,covered by natural grasses. To asses bacterial diversity we used 454-FLXpyrosequencing technology of the V4 region of the 16S rRNA gene, on genomic DNAextracted from soil samples. We obtained 135.918 sequences, representing 3187Operational Taxonomic Units (OTUs) distributed in 12 phyla and 45 classes.Overall, the main identified components of the bacterial community at thePhylum level were Acidobacteria, followed by Verrucomicrobia, Planctomycetesand Chloroflexi. Our results suggest that 5-6 years of land use with L. tenuis promotiondoes not affect the microbial community structure in this ecosystem. NMDSordination in two dimensions based on Bray?Curtis distances and PERMANOVA testdid not show differences in bacterial community composition between paddockspromoted or not with L. tenuis, although differences among sites were detected.In parallel, Pearson?s correlation analysis suggested that L. tenuis promotionwould indirectly affect members of classes Acidobacteria and Anaerolineae,through altering water-related soil properties.promotionwouldindirectlyaffectmembersofsoilproperties.