INTERSPECIFIC DIFFERENCES IN THE NEMATODE SURFACE-COAT BETWEEN MELOIDOGYNE-INCOGNITA AND M-ARENARIA RELATED TO THE ADHESION OF THE BACTERIUM PASTEURIA-PENETRANS

Spores of the bacterium Pasteuria penetrans adhered to second-stage juveniles of both Meloidogyne incognita and M. arenaria, but in standard attachment assays far fewer adhered to the latter species. Similarly, a polyclonal antibody was shown not to recognize the surface coat of M. arenaria but did recognize the surface coat of M. incognita. Although the incubation of whole, intact 2nd-stage juveniles of M. incognita in a series of detergents and protein-denaturing agents at room temperature did not reduce the number of spores adhering after exposure to the bacterium, incubation in buffer (PBS) alone at 100-degrees-C for 2 min did. Immunoblotting of cuticle extracts onto nitrocellulose and probing the blots with antibody showed that the antibody recognized a large protein of M(r) 80 kDa and a series of smaller proteins of approximately 43 kDa on M. incognita which were not recognized in extracts from M. arenaria. As incubation of the 2nd-stage juveniles in antibody prohibited spore attachment it is suggested that these proteins may be involved in spore adhesion. Large differences exist between M. incognita and M. arenaria in the amounts of surface-associated proteins on the 2nd-stage juvenile cuticle.