Plant-Parasitic Nematodes Associated with Certain Fruit Trees and Vegetable Crops in the North Eastern Egypt

This survey was conducted in four locations of Ismailia governorate in the north eastern part of Egypt during the 2020-2022 seasons to investigate occurrence, population density and distribution of plant-parasitic nematodes associated with various crops. A total of 440 soil samples, were collected from infested fruit trees viz. grape ( Vitis vinifera L.), guava ( Psidium guajava L.), olive ( Olea europaea L) and pomegranate ( Punica granatum L.) and vegetable crops viz. green bean ( Phaseolus vulgaris L.), pea ( Pisum sativum L.), strawberry ( Fragaria ananassa ) and tomato ( Solanum lycopersicum L.). Ten plant parasitic nematodes genera have been identified. The root- knot nematodes, Meloidogyne had the highest mean density over any nematode taxa in the tested samples. The highest density values of Meloidogyne were recorded on olive, grape and guava trees that amounted to 800, 640 and 200 juveniles/250 g soil. respectively. However, the maximum densities for Tylenchorhynchus were 160, 180, 120, and 120 juveniles /250 g soil for grape, guava, olive, and pomegranate, respectively. The maximum density values for Helicotylenchus were 180, 120 and 40 juveniles /250 g soil for guava, olive and pomegranate, respectively. Other genera were found at low density i.e. Criconemoides, Trichodorus, Xiphinema, Longidorus, and Pratylenchus . The root knot nematodes have been nearly found in all vegetable crops. The maximum densities for Meloidogyne were 600, 200, 240 and 720 juveniles /250 g soil for green bean, pea, strawberry and tomato, respectively. Generally obtained data indicated that plant-parasitic nematodes are considered as a serious threat to such plant species under variable agronomic and climatic conditions that need to further developed and implemented of control measures.