Rizobactérias promotoras de crescimento de plantas associadas a videiras no Vale do São Francisco

Abstract

The cultivation of fine table grapes in the São Francisco Valley is among the agricultural activities of greatest economic value in the region, mainly for the state of Pernambuco. The production of fine table grapes in the region is based on the conventional cultivation system. However, the depletion of natural resources, the stagnation of productivity over the years and the need to meet the demands of sustainability demand innovations on the part of agriculture. RPCP have mechanisms that can influence plant development and provide improvements in local agricultural productivity, without excessively demanding inputs. In this sense, the present study aimed to evaluate the capacity of rhizobacteria, isolated from the rhizosphere of vines inserted in the São Francisco Valley, to perform the following mechanisms: phosphate solubilization, biological nitrogen fixation, indole-acetic acid production, biofilm formation and direct antibiosis to Xanthomonas camprestris pv. viticola, of which 423 bacteria were tested. Subsequently, 15 RPCP with the best results had their 16S rRNA sequenced. 95 rhizobacteria capable of performing at least one of the six evaluated mechanisms were found. The highest rate of calcium phosphate solubilization was 2.09, indicating low solubilization capacity. Only two rhizobacteria had the enzyme nitrogenase. The highest production of AIA verified was 688 μM. Only 11.27% of the bacteria tested positive for biofilm formation. Percentages of growth inhibition by antibiosis of 100% and 88% were verified. The main associated genera of the RPCPs were: Pseudomonas (20%), Stenotrophomonas (13%) and Bacillus (13%). Therefore, the rhizosphere of vines has rhizobacteria capable of carrying out the tested mechanisms and which are capable of being isolated and manipulated in vitro.