Pseudomonas spp. as growth promoting agents of sunflower and jack bean in soil with sulfentrazone

Abstract

Bacteria that present potential to promote plant growth can bring direct benefits both to the remediating plants and to the soil in the sulfentrazone bioremediation process. In view of this, the objective of this study was to evaluate the inoculation response of bacteria of the genus Pseudomonas in soil contaminated with the herbicide sulfentrazone on the growth of the remediating species jack bean (Canavalia ensiformis) and sunflower (Helianthus annuus). The experiment was conducted in a greenhouse in a completely randomized design with four replicates. For each phytoremediating species, three factors were considered, the first being the presence or absence of inoculation with selected bacterial consortium, the second consisting of cultivation with the same spe­cies or with the other species, and the third corresponding to the bioremediation time (25, 45, 65 and 85 days after thinning). The leaf area and the dry matter of roots, stem and leaves were evaluated at the end of each time and for each of the species. In general, both remediating species showed lower growth when cultivated together with a plant of the same species. In most of the evaluations, inoculation provided greater accumulation of leaf area and dry matter of leaves, stem and roots of Canavalia ensiformis and Helianthus annuus, with increases varying from 18 to 55%. The results showed the ability of Pseudomonas spp. isolates to promote the growth of plants cultivated in soil with sulfentrazone.