Root-knot nematodes: abundance in organic farming, differentiation among populations, microbes attached to juveniles in soil, and bacterial antagonists

Two surveys were conducted to determine the frequency and abundance of plantparasitic nematodes associated with different crops at an organic farm in Egypt, during autumn 2009 and 2011. Eleven genera of plant-parasitic nematodes were detected. Root-knot nematodes (Meloidogyne spp.) showed the highest abundance and frequency of all plant-parasitic nematodes during the two surveys. Commonly detected genera were Tylenchorhynchus, Rotylenchulus, Helicotylenchus and Pratylenchus. Further studies on Meloidogyne were carried out with regard to discrimination among populations, attachment of microbes to juveniles (J2) in soil, and biocontrol through bacterial strains which were known as antagonists of fungal pathogens