Effect of rhizobacteria on the attachment of Pasteuria penetrans endospores to second stage juveniles of Meloidogyne javanica Efeito de rizobacterias na adesao de endosporos de Pasteuria penetrans em juvenis do segundo estadio de Meloidogyne javanica
Freitas, L.G.; Alves, F.R.; Costa, M.J.; Ferraz, S.
Revista Ceres. Julho-Agosto; 49284: 461-465
The first step in the parasitism of Meloidogyne spp. by Pasteuria penetrans is the attachment of the spores to the nematode cuticle, which can be enhanced by physical or biological factors. Spore suspensions of P. penetrans were concentrated by centrifugation, resuspended and incubated in aqueous suspensions of one of the two rhizobacteria isolates (ALT-7 and MI-6), antagonistic to M. javanica, for 5 days at 27deg. C. After incubation, 200 J2 in 1 mL of water were added per tube and centrifuged at 400 G (1500 ipm) for 20 minutes to promote the contact between spores and nematodes. ALT-7 and MI-6 decreased the endospore attachment, when compared to the control treatment, in 91.5 and 51.6% (P &< 0.05), respectively. This reduction might be due to chemical products ofrhizobacteria growth in the medium, which might have degraded or altered the substances responsible for the recognition of the spores by the nematode cuticle.