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During a survey for entomopathogenic nematodes in northern China, a new species of Steinernema was isolated from soil samples collected from Xinhin county, Liaoning province. This nematode was obtained by the insect-baiting technique using last instar larvae of Gallería mellonella. It is described herein as S. xinbinense n. sp. The nematode can be separated from other described species of the group by morphological and morphometric characteristics of the different stages and by characterisation and phylogeny of DNA sequences of the D2D3 domain of the LSU or ITS regions of rDNA. This new species is characterised by the following morphological characters: infective third-stage juvenile with a body length of 694 (635-744) pm, distance from head to excretory pore of 51 (46-53) μm, tail length of 73 (61-81) μzm, E = 71 (65-78)%, presence of eight unevenly spaced and developed ridges in middle lateral field (i.e., nine lines). First generation male with well curved, yellowish spicules 56 (49-62) μm long and gubernaculum 35 (30-41) μm long, small mucron mostly present, first generation female with protruding vulva, tail conical with one or two small muerons and D = 45 (41-50)%. Cross hybridisation tests with S. tielingense, S. kraussei, S.feltiae and S. hebeiense showed that this species was reproductively solated. The analyses of ITS-rDNA and D2D3 sequence confirm that the studied nematode isolate is a valid new species belonging to the 'feltiae-kraussei-oregonense' group. [ABSTRACT FROM AUTHOR]

A new species of Steinernema was isolated from shrub soils in Liaoning province during a survey for entomopathogenic nematodes in north China. This nematode was obtained by the insect-baiting technique using last instar larvae of Galleria mellonella (Lepidoptera: Pyralidae). This new species is described herein as S. tielingense n. sp. It belongs to the 'feltiae-kraussei-oregonense' group and is characterised by infective third-stage juvenile (IJ) with a body length of 915 (824-979) μm, distance from head to excretory pore of 69 (64-73) μm, tail length of 81 (74-85) μm, ratio E=88 (85-94)%, lateral field with eight ridges at mid-body, first generation male spicule 88 (79-98) μm and gubernaculum 61 (49-70) μm long, and first generation female with a vulval protrusion and ratio D=41 (32-49)%. The new species distinctly differs from the related species S. kraussei, S. silvaticum, S. oregonense and S. cholashanense in the different number of ridges in the lateral fields and hyaline tail length as % of total tail length of IJ and male body length and distance from head to excretory pore. Cross hybridisation tests showed that these species were reproductively isolated. The sequences analyses of the internal transcribed spacers (ITS) and D2-D3 regions of the ribosomal DNA confirm this to be a new species. [ABSTRACT FROM AUTHOR]

Bursaphelenchus nematodes, extracted from 12 samples taken from imported packaging wood originating from seven countries and regions at Nanjing, China, during 2003 and 2004, were identified using morphology, morphometric data and ITS-RFLP patterns. Two samples were identified as B. xylophilus: one, from Canada, was the M-form and another, from Japan, the R-form. Five samples were identified as B. mucronatus, three belonging to the European genotype and two to the East-Asian genotype. Two samples (from Germany and South Korea) were recognised as B. rainulfi. Two samples (South Korea and Japan) were identified as B. doui and a sample from Hong Kong was identified as B. thailandae. Additional morphometric data are provided for the identified species, especially with respect to spicule morphometrics. The CDA of morphometric data discriminated the five species by nine male and eight female characters. The characters used for this analysis corresponded partly to the main taxonomic-informative characters for the genus Bursaphelenchus, viz., body length, stylet length, spicule length, a, c and c′ values. The phylogenetic trees constructed from the D2D3 sequence data supported the division of East Asian and European genotype groups of B. mucronatus. Bursaphelenchus doui grouped with B. xylophilus and B. mucronatus, all members of the xylophilus-group, which was separated from B. rainulfi and B. thailandae. [ABSTRACT FROM AUTHOR]

Bursaphelenchus chengi sp. n. is described and illustrated. Dauer juveniles were isolated from imported wood packaging materials from Taiwan to Nanjing Port, China. Bursaphelenchus chengi sp. n. was reared and maintained on Petri dish cultures of the fungus Botrytis cinerea. The new species is characterised by the medium body size in both sexes, the presence of only two incisures in the lateral field and the robust and strongly curved spicules. The spicule lamina is angular distally, the rostrum digitate and the condylus rounded. The tail is arcuate with a pointed terminus. The bursa is usually truncate with the posterior margin indented in some specimens or rounded with a fine axial point. Females have a small vulval flap formed by a short extension of the cuticle of the anterior lip, and a conical tail that gradually tapers to an almost straight or slightly recurved, pointed or rounded terminus. Because of the presence of two lateral lines, similar spicule shape, tapering female tail and the presence of a small vulval flap, B. chengi sp. n. should be grouped in the abietinus-group sensu Braasch. together with B. abietinus, B. antoniae, B. hellenicus, B. hylobianum and B. rainulfi. ITS-RFLP profiles support the proposal of the new species, and phylogenetic analysis of the 28S rDNA D2/D3 domain sequence places it close to B. antoniae and other species of the abietinus-group. [ABSTRACT FROM AUTHOR]

The pine wood nematode (PWN), Bursaphelenchus xylophilus, which in China and East Asia is vectored by Monochamus alternatus, is the causal agent of pine wilt disease of Japanese black pine, Pinus thunbergii. The vector emergence and the transmission of nematodes through vector feeding on pine twigs were monitored during 2004 and 2005 in Nanjing, China. The emergence started from late April to the end of June and peaked from late May to early June. There were 438 and 927 adults collected in 2004 and 2005, respectively, and approximately 70% of the beetles emerged during the peak period. Visual estimation of the nematode burden on vectors by observation of the atrium of the first abdominal spiracle gave unreliable information. The percentage of beetles carrying PWN of the total number of emerged beetles was between 20 and 30%. Seventy percent of the nematodes were released from beetle cadavers after 3 days of extraction. The sex and longevity of the beetle had no significant relationship with the number of nematodes that remained in cadavers. Transmission of nematodes into pine twigs through beetle feeding started 10 days after emergence of the vector. The period of nematode transmission could last for up to 79 days after beetle emergence. Two types of nematode-transmission curve were found by measuring the number of nematodes transmitted into pine twigs per day. The unimodal pattern peaked between 3 and 6 weeks after adult emergence; the bimodal pattern had two transmission peaks: one between 2 and 3 weeks, and another between 5 to 7 weeks after beetle emergence. [ABSTRACT FROM AUTHOR]

A new species of Steinernema (Rhabditida), S. hebeiense sp. n. was isolated from sandy soil, Hebei Province, China. Diagnostic characters of infective juveniles of S. hebeiense sp. n. include total body length of 658 (610-710) μm, distance from anterior end to excretory pore of 48 (43-51) μm, tail length of 66 (63-71) μm, and E% ratio of 72 (65-80). The lateral field has eight ridges at the mid-body region (two very thin submarginal ridges, poorly discernible under light microscope, but visible in SEM); and the anterior end is slightly offset and flattened. First generation males have a body length of 1177 (1036-1450) μm, spicule length = 57 (51-63) μm, and gubernaculum length = 46 (38-50) μm. The spicules are light brown in colour and slightly curved; the manubrium is longer than wide. A tail mucron is present in second generation males. These morphometrical and morphometric features classify S. hebeiense sp. n. within the ' feltiae-kraussei-oregonense ' group. Molecular data also classify the new species within this group. Within this group, the smallest differences between the sequences of S. hebeiense sp. n. is with S. weiseri – 73 bp in the ITS rDNA and 13 bp in the studied partial sequence of the D2D3 expansion segment of LSU rDNA. [ABSTRACT FROM AUTHOR]

Highlights: [•] Virulence of EPN isolates against Bradysia odoriphaga differs between isolates. [•] Heat tolerance (40°C, 2h) differs between EPN species. [•] Cold tolerance (−5°C, 8h) differs between EPN species. [•] Survival of heat or cold-treated EPN is affected by time and IJ concentration. [•] Desiccation tolerance (25% glycerol, 25°C, 72h) differs between EPN species. [ABSTRACT FROM AUTHOR]