MORPHOLOGICAL, MORPHOMETRIC AND MOLECULAR CHARACTERIZATION OF MERLINIUS MICRODORUS (GERAERT, 1966) SIDDIQI, 1970, SCUTYLENCHUS RUGOSUS (SIDDIQI, 1963) SIDDIQI, 1979 (MERLINIIDAE), AND PSILENCHUS CURCUMERUS RAHAMAN, AHMAD AND JAIRAJPURI, 1994 (PSILENCHIDAE) AND APPROACHES TO PHYLOGENETIC RELATIONSHIPS

Abstract

Merlinius microdorus and Scutylenchus rugosus (Merliniidae), and Psilenchus curcumerus (Psilenchidae) were collected from the rhizosphere of faba bean (Vicia faba L.) fields in Khuzestan province, south-western Iran. Morphological and morphometric data are provided for these species. Additionally, sequences of the D2-D3 expansion segments of 28S rRNA gene for all species were also used for molecular phylogenetic analysis. The phylogenetic relationships of Psilenchidae and Merliniidae in relation to representatives of the superfamily Tylenchoidea, obtained from Bayesian inference (BI) and maximum likelihood (ML) analyses of the D2-D3 sequences, are presented and discussed. The results of phylogenetic analysis strongly supported (BPP = 100) Merliniidae and Psilenchidae as monophyletic. The family Tylenchidae formed a sister clade to Merliniidae/Psilenchidae with high branch support (BPP = 100). Monophyly of representatives of Merliniidae (including Pratylenchoides) was supported with maximum BPP