Agrupamento de rizobactérias nativas da região oeste do Paraná por estudo de congruência genética e bioquímica

Abstract

In the search for agronomic alternatives that are less aggressive to the environment, the substitution of mineral fertilizers by biofertilizers based on plant-beneficial micro-organisms was initiated, among them plant growth promoting bacteria. The objective of this work was to characterize rhizobacteria isolated from soils with different crop managements, grouping the samples based on their genetic characteristics (16S rDNA sequencing, amplification of the ITS 16–23S rDNA region, feoB, entC and entF genes) and biochemical (indole-acetic acid (IAA) production, acetoin production and phosphate solubilization), and verify their diversity within groups. Based on the results, the presence of the genes feoB, entF and entC was verified in 81.5%, 48.1% and 81.5% of the samples, respectively. Most of the strains (96.3%) had the capacity to produce IAA, 59.2% were able to produce acetoin and 81.5% of them to solubilize phosphate. By the analysis of congruence and grouping, there was similarity of genetic or biochemical patterns between the groups; however, there was great diversity among the isolates within each group. In general, it was observed that the conservationist managements presented the best performances. The study revealed that strains 130, 219, 302 and 326 presented biotechnological potential for at least two of the characteristics evaluated.