First Record of Meloidogyne javanica (Treub, 1885) (Chitwood, 1949) in Lettuce (Lactuca sativa L.) Growing Areas in the Southern Marmara Region
 ABSTRACT
 The estimated loss of the annual agricultural production due to plant parasitic nematodes, which are among the important soil-borne pathogens, is estimated to be approximately 118 billion US dollars. Root-knot nematodes are the most important plant parasitic nematode group due to their wide host range and difficulties in control and cause significant quality and yield losses in vegetables including lettuce plant. Root-knot nematodes are causing symptoms such as yellowing, wilting and stunting on lettuce plant. For monitoring lettuce fields for detecting nematode infected areas, surveys were made to the lettuce growing areas of Çanakkale province in the winter months of 2021-2022 and the plants infected with root-knot nematodes were examined and pure nematode cultures were obtained in the laboratory. Species identification was made using morphological methods and morphometric measurements from second-stage infective juvenile and female individuals obtained from pure cultures. As a result, the first record of M. javanica in lettuce growing areas in the Southern Marmara Region was made in this study.
 Keywords: Lettuce, Southern Marmara Region, Root-knot nematode