A survey was conducted to determine the frequency of occurrence and population densities of plant-parasitic nematodes associated with nine major fruit trees. In citrus soil and root samples collected from Alexandria, El-Behera and Kafr El-Sheikh governorates, the citrus nematode, Tylenchulus semipenetrans was the most prevalent pest, with frequency of occurrence (FO) of 36.8-66.7% and population densities of 288-495 individuals/250 g soil. In soil and root samples collected from the other surveyed fruit trees, the root-knot nematodes (Meloidogyne spp.) were the most prevalent nematodes with FO of 40.0-52.8% and population densities of 295-554 juveniles/250 g soil. Also, Hemicriconemoides mangifera, Helicotylenchus microcephalus, Pratylenchus penetrans, P. thornei and Xiphinema elongatum were common, with FO of 24.3-33.3% and population densities of 205-285 individuals/250 g soil. Meanwhile, Aphelenchoides spp., Hoplolaimus spp., Longidorus spp., Trichodours spp. and Psilenchus spp. were less common, with FO of 4.3-10.8% and population densities of 35-95 individuals/250 g soil.
Key words: Northern Egypt, Fruit trees, Nematode, Phytoparasitic nematodes.
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