Plant Parasitic Nematodes Associated with Wheat in Northern and Middle Egypt

Distribution and identification of phytonematodes associated with wheat grown in twelve provinces of Northern and Middle Egypt were investigated during two growing seasons (2016-2017 and 2017-2018). A total of 929 soil and root samples were collected from 119 localities (villages/farms) belonging to 37 districts. Samples contained fourteen nematode genera and species viz., Aphelenchoides, Criconemella, Ditylenchus, Helicotylenchus, Heterodera, Hirschmanniella oryzae, Hoplolaimus, Longidorus,Meloidogyne, Pratylenchus, Rotylenchulus reniformis, Tylenchorhynchus, Ttylenchus and Xiphinema. The stunt nematodes (Tylenchorhynchus spp.), the root-lesion nematodes (Pratylenchus spp.), the spiral nematodes (Helicotylenchus spp.) and the cyst nematodes (Heterodera spp.) were the most frequent nematodes in all samples. The stunt nematodes had the highest occurrence with 47.4%, population density with 48.2 and prominence value with 33.2. The root-lesion nematodes ranked the second after Tylenchorhynchus spp., in terms of frequency of occurrence (13.77%), while the cyst nematodes had the second order after the stunt nematodes, in terms of population density (24.8) and prominence value (5.4). The spiral nematodes occupied the third rank, in terms of frequency of occurrence (5.5%), and the last rank in terms of both of population density and prominence value (9 and 2.1, respectively).