COMPATIBILITY BETWEEN PASTEURIA-PENETRANS ISOLATES AND MELOIDOGYNE POPULATIONS FROM SPAIN

Several populations of Pasteuria isolated from fields in Spain were co mpared with other Pasteuria populations, held in collections at the In stitute de Recerca i Tecnologia, Agroalimentaries (IRTA), Cabrils or I ACR-Rothamsted, for their ability to adhere to and infect root-knot ne matodes (Meloidogyne spp.) grown on host plants differing in their sus ceptibility to root-knot nematodes. The results showed a high level of variation in bath the ability of a population of Pasteuria to adhere to a particular population of nematode and vice versa. In particular t he isolates of Pasteuria originating from M. hapla retained a high lev el of specificity for the species from which they originated. The infe ction of the nematodes by the bacteria was generally low, even when ne matodes were encumbered with relatively high levels of spores. It is s uggested that prolonged storage (6 years) may reduce the ability of sp ores to infect nematodes independently of adhesion.