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The Korean cyst nematode, Heterodera koreana, was recorded for the first time from Japan and characterised morphologically, morphometrically and molecularly. In total, 41 populations were detected from soil samples collected from the rhizosphere of four bamboo species in Japan: 31 populations from moso bamboo (Phyllostachys edulis), seven from madake (P. bambusoides), two from henon bamboo (P. nigra var. henonis) and one from fish pole bamboo (P. aurea). The morphology and morphometrics of the Japanese population were in agreement with those of the original description of H. koreana from South Korea and other subsequent descriptions from China and Iran, with the exception of some minor differences. The results of the phylogenetic analyses of the D2-D3 expansion segments of 28S rRNA gene and ITS rRNA gene sequences confirmed the species identification and phylogenetic relationship of H. koreana with other Heterodera species. The COI mtDNA gene sequences were obtained for the first time for H. koreana. Three COI haplotypes found in Japanese H. koreana populations showed a characteristic geographical distribution in Japan.

The reniform nematodes of the genus Rotylenchulus are semi-endoparasites of numerous herbaceous and woody plant roots and are mainly distributed in tropical and subtropical regions. In this study, we provide morphological and molecular characterisation of six out of ten presently known valid species of Rotylenchulus: R. clavicaudatus, R. leptus, R. macrodoratus, R. macrosoma, R. reniformis and R. sacchari from South Africa, USA, Italy and Spain. Rotylenchulus parvus was only studied morphologically. A new species, R. macrosomoides sp. n., isolated from soil and roots of sugarcane in South Africa, is described. The phylogeny of Rotylenchulus, as inferred from the analyses of D2-D3 of 28S rRNA, ITS rRNA, coxI mtDNA and hsp90 gene sequences, is presented. The study revealed that R. reniformis and R. macrosoma have a sister relationship, but that relationships between other Rotylenchulus species remain unresolved. The phylogenetic analysis also confirmed the hypothesis that this genus originated from the Afrotropical zoogeographical region. Our study revealed that R. reniformis and R. macrosomoides sp. n. have two distinct rRNA gene types and R. macrosoma have three rRNA gene types in their genomes. PCR with species-specific primers was developed for rapid diagnostics of R. reniformis., Pablo Castillo acknowledges support from the grant AGL2012-37521 from the ‘Ministerio de Economía y Competitividad’ of Spain, grant P12-AGR 1486 and grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía and Unión Europea, Fondo Europeo de Desarrollo regional, ‘Una manera de hacer Europa’ and Sergei A. Subbotin acknowledges support from the Russian Foundation of Basic Research, project number 14-04-00953.

A lesion nematode population infecting citrus in the state of Sao Paulo, Brazil is described and named Pratylenchus jaehni sp. n. Biological, molecular and morphological characteristics of this new species are compared with those of the morphologically similar P. coffeae and P. loosi. Results of mating experiments showed that R jaehni is reproductively isolated from P coffeae. Molecular (D2/D3 DNA sequences) dissimilarities among P. jaehni sp, n., P. coffeae and P. loosi were documented in a previous study. The morphology of seven R coffeae populations from tropical America and eastern Java and a P loosi population from Sri Lanka is used for comparison with the morphology of P. jaehni sp. n. Pratylenchus jaehni differs from R coffeae and P. loosi by only a few morphological ;characters of the females. The mean values of stylet length, stylet knob height, and vulva position are smaller (less than or equal to15 vs greater than or equal to15 mum, less than or equal to2.7 vs greater than or equal to2.7 mum, less than or equal to79 vs greater than or equal to79%) than those in P coffeae and P loosi. The tail terminus is usually subhemispherical and smooth in P jaehni sp. n.. whereas it is commonly truncate and indented in most P. coffeae populations and bluntly or finely pointed in P. loosi. Because of the morphological similarities among P. jaehni sp. n., P. coffeae and P. loosi, examination of at least ten specimens is required to obtain a reliable diagnosis based on morphology. Nineteen morphometric parameters for P. jaehni sp. n. and P. coffeae ranged from 0-13% smaller in fixed than in live specimens.

Systematic nematode surveys for criconematids in the coastal sand dunes of southern Spain and on the Atlantic coast of Florida, USA, revealed the presence of three populations of sheathoid nematodes identified as Hemicriconemoides promissus, H. ortonwilliamsi and H. wessoni. All of them belong to the fourth group proposed by Decraemer and Geraert (1992) as they are characterised by wide body annuli ca ≥ 5 μm wide and a stylet ca 50 μm long, although all have a distinctly different female tail shape. Comparative SEM studies on H. cocophillus, H. mangiferae, H. brachyurus and H. promissus were done. SEM studies from paratype material and female specimens of a newly discovered population from Spain, confirmed the absence of lateral vulval flaps for both H. promissus populations, justifying the rejection of the synonymy proposed by Germani and Anderson (1991), and the re-establishment of H. promissus as a species distinct from H. brachyurus. The present records of H. promissus and H. ortonwilliamsi extend their geographical distribution from Italy to an additional Mediterranean country and constitute the first reports of both species in Spain. Additional morphometric data and illustrations of a Pensacola, FL, USA, population of H. wessoni, the type species of the genus, are also presented.

Abstract The evolutionary relationships of 82 species of tylenchid and aphelenchid nematodes were evaluated by use of sequence data of the D2 and D3 expansion fragments of the 28S ribosomal RNA genes. Nine automatic and one culled sequence alignments were analysed using maximum parsimony and Bayesian inference approaches. The molecular data sets showed that the order Tylenchida comprises lineages that largely correspond to two suborders, Hoplolaimina and Criconematina, and other taxonomic divisions as proposed by Siddiqi (2000). Several significant results also derived from our study include: i) the basal position of groups that include entomoparasitic nematodes within tylenchid trees; ii) paraphyly of the superfamily Dolichodoroidea sensu Siddiqi (2000); iii) evidence for a Pratylenchus, Hirschmanniella and Meloidogyne clade; and iv) lack of support for widely held traditional placement of Radopholus within Pratylenchidae and placement of this genus within Hoplolaimidae or Heteroderidae. Congruence and incongruence of molecular phylogeny and traditional classifications and morphological-based hypotheses of phylogeny of tylenchids are discussed.

The foliar nematode species Aphelenchoides ritzemabosi is reported attacking sweet basil in glasshouses in the province of Imperia, northwest Italy. The nematode colonised and reproduced within the leaf, petiole and stem tissues. The epidermis and mesophyll were invaded by the nematode which caused internerval discoloration and necrosis and collapse of the palisade and spongy parenchyma. All nematode developmental stages, including eggs, were observed in the leaf tissues. Morphology and morphometrics of A. ritzemabosi from chlorotic and necrotic leaf tissues are presented. Possible control measures, which are complicated by the short life cycle of the nematode, the broad host range, and the short productive cycle of basil, are also discussed, together with the risk of an erroneous field diagnosis caused by difficulty in differentiating the symptoms of basil downy mildew and basil black spot from those of the foliar nematode.

The suborder Criconematina is a large group of ecto- and endoparasitic nematodes, including several species of major agricultural importance. The D2-D3 expansion segments of the 28S nuclear ribosomal RNA gene were amplified and sequenced from 23 nominal and six unidentified species from the genera Mesocriconema, Criconemoides, Ogma, Criconema, Xenocriconemella, Hemicriconemoides, Hemicycliophora, Paratylenchus, Tylenchulus, Trophonema and Sphaeronema, together with outgroup taxa from Tylenchidae (Aglenchus) and Atylenchidae (Eutylenchus). A sequence alignment optimised using the secondary structure model was analysed using maximum parsimony, maximum likelihood and Bayesian inference approaches under two models. All analyses yielded a similar topology with differences primarily in the position of poorly supported clades. Although some molecular trees differ from the previous morphologically based hypotheses of criconematid phylogeny, maximum likelihood tests did not yield statistically significant differences between some of the tested classical morphological and molecular topologies. DNA data support monophyly for the genera Mesocriconema, Hemicriconemoides and Criconema and reject the hypothesis of a single origin of criconematids with a cuticular sheath or 'double cuticle'. Application of the complex model of rRNA evolution, considering paired nucleotides for the stem and unpaired nucleotides for the loop region, resulted in a majority rule consensus Bayesian tree with unresolved relationships between main clades. This lack of resolution is expected by the low number of independently evolving nucleotides. Sequence divergence in this DNA segment between populations of Mesocriconema xenoplax, M. sphaerocephalum and Hemicriconemoides cocophillus suggest the presence of several sibling species under these taxa names.

6 pages, 2 figures.-- Full-text version available at: http://www.ias.csic.es/pcastillo/nematology-6-749-754.pdf, SEM studies on a Meloidogyne baetica population provided additional details of the external morphology for female, male and second-stage juveniles. The labial disc in female and male specimens is fused with the medial lips forming a single structure. In second-stage juveniles the lateral lips are triangular with rounded margins. The amphidial opening for all life stages appears oval to rectangular in shape and is located between the labial disc and lateral lips. Lateral fields of male and second-stage juveniles have four incisures irregularly areolated along the entire body. The results of a host-range study for additional natural hosts of M. baetica conducted in wild olive communities growing at Vejer de la Frontera (Cádiz province) in southern Spain are also reported. Apart from the type host, M. baetica was found to infect two natural woody host plants, lentisc (Pistacia lentiscus) and Aristolochia baetica. Hostparasite relationships in these new hosts confirmed the typical susceptible reaction observed in wild and cultivated olives. Similarly, the reproductive fitness, evaluated as the number of eggs per egg mass, was not significantly different in all plant hosts. No infections or galled roots were observed in herbaceous plant species studied and M. baetica must therefore be considered as a parasite of woody plants.

Abstract Severe root infection of wild olive (Olea europea L. ssp. sylvestris), together with heavy soil infestation by the reniform nematode Rotylenchulus macrosoma, was detected in a natural wild olive orchard on sandy soil in Cádiz province, Andalucía, southern Spain. Most, but not all, of the morphometric characters of this population agreed with those reported for immature and adult females and males in previously studied populations. Sedentary immature and mature females showed a semi-endoparasitic feeding habit in wild and cultivated olives (cvs Arbequina and Picual). Naturally infected roots of wild olive responded to nematode infection identically to artificially infected olive planting stocks. The feeding site induced by R. macrosoma on olive roots consists of a stelar syncytium, which originates from an endodermal cell enlarging by a curved sheet of pericycle cells formed by hypertrophy of pericycle cells adjacent to the feeding cell. There were obvious anatomical differences between the feeding sites induced by R. macrosoma and R. macrodoratus on olive roots.

Trophonema okamotoi populations from Florida showed intraspecific morphometric variability and did not differ from those from Costa Rica and Venezuela. Swollen females of these populations had tapering tails with bluntly rounded or small rounded termini like those of T. okamotoi paratypes from Japan and unlike the pointed or minutely digitate tail termini of T. arenarium paratypes from California. Hosts of T. okamotoi were Liquidambar syraciflua and an uncultivated tropical grass in Florida, and Gyranthera caribensis in Venezuela. At 22 ± 2° C embryogenic development of T. okamotoi was completed in 14 days and the first-stage juvenile moulted in the egg 16 days after egg deposition. Swollen females, males, second-stage juveniles, and eggs (50-120 eggs per female) were covered by a soft or hardened gelatinous matrix, which was produced by the secretory-excretory cell, and exuded through the secretory-excretory pore. Histological observations of L. styraciflua and tropical grass roots infected by T. okamotoi showed this species to be a cortical feeder. Females penetrated the epidermis of L. styraciflua roots and also 5-6 cortical layers in the roots of the tropical grass. They established a syncytium in the cortex.