identification of two sub order tylenchina and aphelenchina nematodes from tomato fields in northern khorasan province

in order to identify the plant parasitic nematodes of tomato fields in northern khorasan province, 50 soil and root samples were collected during 2009 - 2010. nematodes were extracted by combined sieving and centrifugal-flotation method and processed to be transferred to glycerin. after preparing microscope slides, the morphological and morphometrical characters of the nematodes were studied using the light microscope equipped with a drawing tube. twenty four species from 16 genera were identified as follow: aphelenchoides lanceolatus ، a. richardsoni ، a. tuzeti ، aphelenchus avenae ، a. isomerus ، basiria graminophila ، boleodorus thylactus ، filenchus cylindricaudus ، f. thornei ، f. vulgaris ، geocenamus tenuidens ، helicotylenchus digonicus، h. dihystera ، h. pseudorobustus ، irantylenchus clavidorus ، meloidogyne javanica ، merlinius brevidens ، neopsilenchus magnidens ، pratylenchus coffeae ، p. thornei ، psilenchus iranicus ، seinura tenuicaudata ، tylenchorhynchus solani، zygotylenchus guevarai that some of them are plant parasitic nematodes. most of the mentioned nematodes have been already recorded from iran. three species namely aphelenchoides tuzeti, geocenamus tenuidens, seinura tenuidens, are reported for the first time from iran.