گزارش سیزده گونه از نماتدهای خانواده Longidoridae از استان آذربایجان شرقی

The Longidoridae family consists of nearly 480 species belonging to different genera including Xiphinema, Longidorus, Longidoroides, Paralongidorus, Australodorus, Paraxiphidorus and Xiphidorus. This group of nematodes include cryptic species that are morphologically indistinguishable but phylogenetically different from each other. Therefore, as in other nematode groups, molecular procedures have also been developed in this group of nematodes. Since the species of this family are important plant parasitic nematodes and considered as vectors of well-known Nepoviruses, their accurate identification is important in terms of the management of viral plant diseases as well as adopting the quarantine measures. In order to study the species of this family, more than 500 soil samples were randomly collected from the rhizosphere of various plants from East Azarbaijan province during 2016 and 2017. The extraction of nematodes was performed using modified Brown and Boag’s method and microscopic slides prepared. Morphological and morphometric characteristics of the specimens were studied using the literature and the identification of species was carried out based on valid keys. In the molecular section, the DNA of the nematodes was extracted and amplified by the primers related to ITS1 rDNA and D2-D3 28SrDNA, regions. The resulting fragments were sequenced and drawing of the phylogenetic tree was done using appropriate software. In this research, five species of X. americanum group namely, X. simile, X. pachtaicum, X.americanum, Xiphinema sp.1 and Xiphinema sp.2, four species of Longidorus including L. apulus, L. proximus,L.iranicus and L. persicus and four species, X.aceri, X. ingens, X. vuittenezi and X. index of Xiphinema non- americanum group were identified. Among the species mentioned above, X. aceri and X. simile have not previously been reported from Iran, and Xiphinema sp.1 is distinguished from X. astaregiensie and X. plesiopachtaicum with the posterior probabilities (PP) of 0.62 and 0.65 as in phylogenetic tree, respectively. Xiphinema sp.2 is also likely to be different, despite being in the associated cluster of the X. chambersi isolates, due to the length of the branch and the posterior probability of 0.99. Except X. ingens, L. iranicus and L. persicus for other species, there is no gene sequencing in Gene bank from Iran, and for the first time, the nucleotide sequence amplified with D2-D3 primer for X. aceri and the sequence amplified with D2-D3 and ITS1 primers for L. Proximus is deposited in the Gene bank.