گزارش گونه‌ی (Meloidogyne javanica) از مزارع چغندرقند در استان آذربایجان‌غربی

Root-knot nematodes belong to the Meloidogynidae family and the genus Meloidogyne, which currently has about 100 known species in the world. These nematodes are endoparasite of roots, and by causing morphological and physiological changes in the plant, including the formation of giant cells and galls, cause the economic damage to many agricultural products, especially in tropical and subtropical regions. In this study, 343 soil samples were collected from sugar beet fields which have contracts with sugar factories in West Azerbaijan Province in 2024. Adult females were separated from infected tissues, and Second stage juveniles (J2s) were extracted from the female nematode egg sac, and permanent slides were prepared from them after the fixation process. The roots of the infected plants were also stained and the female nematodes were used to study the morphology and prepare the perineal pattern. A total of 25 samples infected with root-knot nematodes were identified and the presence of root-knot nematodes was detected in the rhizosphere and also in the roots of sugar beet. The results of the morphological and morphometric studies showed that root knot nematodes belonged to the species Meloidogyne javanica and the morphological and morphometric characteristics are completely consistent with the characteristics of this species. After extracting DNA from an egg mass of nematode, using species-specific primers (Fjav and Rjav), and the correctness of initial identifications was checked and after observing the specific band of this species, it was confirmed. So far, M. javanica has been reported from sugar beet fields in East Azarbaijan, Ardabil, Sistan and Baluchistan, Razavi Khorasan, Isfahan, Hamadan, Alborz and Semnan provinces, and in this research, it is reported for the first time from sugar beet fields in West Azerbaijan province. This nematode still does not have a high distribution in the sugar beet fields of the province, but it seems to be spreading. It should be noted that this species was previously identified from cabbage and squash in West Azarbaijan province.