Avaliação de rizobactérias de solo antrópico, na promoção de crescimento e na indução de resistência contra mancha-alvo do tomateiro (Solanum lycopersicum L.)

Abstract

The soils are home to large number of microorganisms that have beneficial effects to plants. The rhizobacteria are a group of bacteria that have the ability to provide beneficial effects promoting plant growth but also induced systemic resistance (IRS) plans action against pathogens. The objective of this study was to isolate rhizobacteria of rhizoplane of vegetables grown in anthropic soil, and assess their ability to promote growth in tomato seedlings and induce systemic resistance to target spot (Corynespora cassiicola) of tomato. 250 bacterial strains were isolated of which 93 were confirmed in the in vitro evaluation of root colonization of tomato. 14 of 93 strains were obtained by screening for growth promotion. The evaluation of growth promotion testing showed the 14 rhizobacteria isolates and ISO-91 ISO-96 as the most promising for field tests. In the induction of systemic resistance, 11 isolates yielded an incidence seedlings from 1.5 to 2.0 leaf diseases. Plants inoculated with isolates ISO-04, ISO 08, ISO 39 and ISO-172 had a lower disease severity.