Sixteen species, Amplimerlinius globigerus, A. macrurus, Bitylenchus parvus, Merlinius brevidens, M. nanus, Neodolichorhynchus phaseoli, Paramerlinius neohexagrammus, Pratylenchoides alkani, P. ritteri, P. utahensis, Scutylenchus paniculoides, S. rugosus, S. tartuensis, Scutylenchus sp. A, Trophurus impar and Tylenchorhynchus brassicae, from the families Teloty lenchidae and Merliniidae were collected from different locations in Iran and molecularly characterised using sequencing of the D2D3 expansion fragments of the 28S rRNA gene. Morphometries and light micrography for studied species are also provided as vouchers. The phylogenetic relationships of Telotylenchidae and Merliniidae with other representatives of the order Tylenchida, as obtained from Bayesian inference and Maximum likelihood analysis of partial 28S rRNA gene sequences, are presented and discussed. The results of phylogenetic analysis were in accordance with classifications in which Bitylenchus and Scutylenchus are considered as separate genera, but Tessellus and Telotylenchus were synonyms of Tylenchorhynchus. The Shimodaira-Hasegawa test of the 28S rRNA gene sequence alignment and trees rejected a large genus concept of Tylenchorhynchus and the constrained monophyly for Belonolaimidae revealed within this family two genera groups: i) Belonolaimus and Ibipora', and it) Carphodorus and Morulaimus. The present results also support the combination of Pratylenchoides and Merliniinae into a single family, the Merliniidae.

Summary - During 2002During -2004, a survey of entomopathogenic nematodes was conducted for the first time in Iran throughout the three provinces in the north-west of the country. Soil samples were tested for the presence of steinernematid and heterorhabditid nematodes by baiting with Galleria mellonella larvae. Of the 833 soil samples studied 27 were positive for entomopathogenic nematodes (3.2%), with 17 (2.0%) containing Heterorhabditis and ten (1.2%) Steinernema isolates. Morphological and molecular studies were carried out to characterise isolates. The Heterorhabditis isolates were identified as Heterorhabditis bacteriophora and Steinernema as Steinernema carpocapsae, S. bicornutum and S. feltiae. Heterorhabditis bacteriophora was the most common species, which was isolated from 17 sites across the three provinces. Steinernema feltiae was the most common species of Steinernema, which was isolated from eight sites but in only two provinces. Steinernema carpocapsae and S. bicornutum were each isolated from only one site. Steinernema spp. were isolated mainly from orchards and grasslands but Heterorhabditis was isolated mainly from grasslands and alfalfa fields.

Hemocyte encapsulation reactions of infective juveniles of two Iranian isolates of the entomopathogenic nematodes, Heterorhabditis bacteriophora Poinar (Rhabditina: Heterorhabditidae) and Steinernema feltiae Filipjev (Tylenchina: Steinernematidae), were compared in the economic pest Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae), and the greater wax moth, Galleria mellonella L. (Lepidoptera: Pyralidae). The former was a more responsive host than the latter and the hemocyte responses occurred sooner and more extensively. Complete encapsulation of some of the nematodes occurred by 4 h post injection for H. bacteriophora in both L. decemlineata and G. mellonella, and by 2 h pi for S. feltiae in L. decemlineata. The percentage of encapsulation from 24 h to 72 h pi in L. decemlineata was 86.2% for S. feltiae and 39% for H. bacteriophora. In G. mellonella there were no encapsulation or melanization responses against S. feltiae, whereas when H. bacteriophora was encapsulated and melanized (16.7%) the encapsulation level was lower than in L. decemlineata. This study may contribute to effectively selecting entomopathogenic nematode species active against significant economic pests based on the latter's cellular immune response.

Bacillus thuringiensis var. kurstaki (Berliner) has been suggested as a biological control agent for Tuta absoluta (Meyrick). The objective of this study was to determine the interaction between abamectin, azadirachtin, indoxacarb chlorantraniliprole, dichlorvos and metaflumizone with Bt. Effect of recommended doses of the chemical insecticides on colonization of Bt was also investigated in culture medium. Except for metaflumizone, none of the chemicals tested reduced the colonization of Bt compared with control. Interaction between Bt and the chemical insecticides on 2 nd instar larvae was also assessed. In interaction tests, Bt was applied at LC50 * Corresponding author: mjhejazi@tabrizu.ac.ir, Downloaded by [UQ Library] at 02:03 03 February 2015A c c e p t e d M a n u s c r i p t 2 level, 0, 12, 24 or 36 h after treating the larvae with LC10 or LC25 of the chemical insecticides.An antagonistic effect was observed in all treatments where Bt was applied immediately after the chemical insecticide. Also, antagonism was observed when treatment with Bt was done 12 h after azadirachtin and metaflumizone applications. Applying Bt 12 and 24 h after treatment with LC25 of chlorantraniliprole, dichlorvos and abamectin resulted in synergism. But, synergism with LC10 of dichlorvos and abamectin was observed only after 12 h. Additive effect was observed in the rest of the time and concentration combinations. Based on the results obtained, simultaneous use of the chemical insecticides tested and Bt is not recommended for T. absoluta control; and an appropriate time interval should be taken into consideration accordingly.

To determine the LC 50 values of two entomopathogenic nematodes against Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) prepupae, different concentrations of the nematodes were tested in soil. Because of the different temperature requirements of the two nematode species, bioassay experiments were conducted at 20 ± 1°C and 27 ± 2°C for Steinernema feltiae Filipjev (Rhabditida: Steinernematidae) and Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae), respectively. Both the isolates were effective against L. decemlineata. LC 50 values of H. bacteriophora against progeny of field-collected adults and laboratory-reared adults were estimated as 8.5 and 7.6 IJ per prepupa, respectively. For S. feltiae the value was calculated as 51.2 IJ per prepupa against offspring of laboratory-reared adults of L. decemlineata only. Cellular encapsulation of both nematode species was observed. Sublethal nematode concentrations caused wing deformation and delayed metamorphosis which may affect Colorado potato beetle adult fitness.

Longidorus kheirii n. sp., a parthenogenetic species, was found in soil samples collected from the rhizosphere of Rosa sp. growing in a natural mountainous region close to Maragheh city, northwestern Iran. It is characterised by having a long body (6.7-9 mm), a 19.5-23 mum wide head continuous with the body contour, a truncate and slightly concave lip region with convex sides between the anterior end and the guide-ring, an odontostyle 113-130 mum long, an odontophore 69-97.5 mum long, a body width of 90.5-117.5 mum at the mid-body, a long, wide oesophageal bulb (149.5-193.5 x 39.5-48 mum), a tail length of 47-72 mum, a male with 11 ventromedian supplements and spicules of 85 mum in length, and four juvenile stages. The ribosomal 18S rDNA gene of L. kheirii n. sp., L. leptocephalus Hooper, 1961, L. profundorum Hooper, 1966 L. euonymus Mali & Hooper, 1973 and two unidentified species listed as Longidorus sp. 1 and Longidorus sp. 2, all recovered from northwestern Iran in the same survey, and the ITS1 of L. kheirii n. sp. and Longidorus sp. 1 were sequenced in order to investigate the phylogenetic relationships with other previously sequenced Longidorus species.

Xiphinema iranicum n. sp. is described from soil samples collected about the rhizosphere of Rosa sp. growing in a natural mountainous region close to Maragheh city, north-western Iran. The new species belongs to group 6 of the polytomous key to species identification and is unique by having a medium body length (3.8-4.3 mm), odontostyle length of 141-162 μm, odontophore length of 90-98 μm, mid-body diam. of 69-88 μm, presence of spines in the uterus and a hemispherical to conoid tail with a rounded terminus or minute bulge. It resembles X. ingens, X. aceri, X. aequum, X. smoliki, X. illyricum, X. macedonicum and X. vuittenezi but differs from X. aceri and X. aequum by having different tail shape, longer odontophore, lower ratio a, higher ratio c and lower ratio c . Compared to X. ingens and X. smoliki, it differs by having lower ratio a, lower ratio b, spines in uterus vs crystalline bodies plus pseudo Z-organ in X. ingens and spines plus pseudo Z-organ in X. smoliki and also by the presence of rare males, and, finally, it can be distinguished from X. vuittenezi by body and odontostyle length, characters of juveniles and molecular differences. The new species has similar polytomous identification codes to X. illyricum and X. macedonicum but can be differentiated from both by longer body, higher ratio c, higher V, longer odontostyle and odontophore and larger body diam. at mid-body and anus level. Ribosomal gene 18S rDNA and ITS1 of X. iranicum n. sp., X. aceri, X. montenegrinum and X. macedonicum, all obtained from north-western Iran in the same survey, were sequenced to investigate the phylogenetic relationships with other sequenced Xiphinema species.

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