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As a result of the scarcity of informative morphological and anatomical characters, nematode systematics have always been volatile. Differences in the appreciation of these characters have resulted in numerous classifications and this greatly confuses scientific communication. An advantage of the use of molecular data is that it allows for an enormous expansion of the number of characters. Here we present a phylogenetic tree based on 1215 small subunit ribosomal DNA sequences (ca 1700 bp each) covering a wide range of nematode taxa. Of the 19 nematode orders mentioned by De Ley et al. (2006) 15 are represented here. Compared with Holterman et al. (2006) the number of taxa analysed has been tripled. This did not result in major changes in the clade subdivision of the phylum, although a decrease in the number of well supported nodes was observed. Especially at the family level and below we observed a considerable congruence between morphology and ribosomal DNA-based nematode systematics and, in case of discrepancies, morphological or anatomical support could be found for the alternative grouping in most instances. The extensiveness of convergent evolution is one of the most striking phenomena observed in the phylogenetic tree presented here - it is hard to find a morphological, ecological or biological characteristic that has not arisen at least twice during nematode evolution. Convergent evolution appears to be an important additional explanation for the seemingly persistent volatility of nematode systematics. [ABSTRACT FROM AUTHOR]

The root-knot nematode Meloidogyne ulmi is synonymised with Meloidogyne mali based on morphological and morphometric similarities, common hosts, as well as biochemical similarities at both protein and DNA levels. M. mali was first described in Japan on Malus prunifolia Borkh.; and M. ulmi in Italy on Ulmus chenmoui W.C. Cheng. Morphological and morphometric studies of their holo- and paratypes revealed important similarities in the major characters as well as some general variability in a few others. Host test also showed that besides the two species being able to parasitize the type hosts of the other, they share some other common hosts. Our study of the esterase and malate dehydrogenase isozyme phenotypes of some M. ulmi populations gave a perfectly comparable result to that already known for M. mali. Finally, phylogenetic studies of their SSU and LSU rDNA sequence data revealed that the two are not distinguishable at DNA level. All these put together, leave strong evidences to support the fact that M. ulmi is not a valid species, but a junior synonym of M. mali. Brief discussion on the biology and life cycle of M. mali is given. An overview of all known hosts and the possible distribution of M. mali in Europe are also presented. [ABSTRACT FROM AUTHOR]

Meloidoderita salina sp. n. is described and illustrated from the halophytic plant Atriplex portulacoides L. (sea purslane) growing in a micro-tidal salt marsh in the Mont-Saint-Michel Bay in France. This new species is the first member of Meloidoderita Poghossian, 1966 collected from a saline environment, and is characterized by the following features: sedentary mature females having a small swollen body with a clear posterior protuberance; slightly dorsally curved stylet, 19.9 μm long, with posteriorly sloping knobs; neck region irregular in shape and twisted; well developed secretory-excretory (S-E) pore, with markedly sclerotized S-E duct running posteriorly; prominent uterus bordered by a thick hyaline wall and filled with eggs. The adult female transforms into a cystoid. Eggs are deposited in both egg-mass and cystoid. Cystoids of Meloidoderita salina sp. n. display a unique sub-cuticular hexagonal beaded pattern. Male without stylet, pharyngeal region degenerated, S-E duct prominent, deirids small, developed testis 97.5 μm long, spicules 18.4 μm long, cloacal opening ventrally protruded, small phasmids posterior to cloaca opening and situated at 5.9 (3.2-7.7) μm from tail end, and conical tail ending in a rounded terminus marked with one (rarely two) ventrally positioned mucro. Additionally, some young males of the new species were observed enveloped in the last J2 cuticle. Second-stage juvenile body 470 μm long, with a 16.4 μm long stylet, prominent rounded knobs set off from the shaft, hemizonid anterior and adjacent to S-E pore, small deirids located just above S-E pore level, genital primordium located at 68-77% of body length, phasmids small and located at about 19 μm from tail tip, and tail 38.7 μm long, tapering to finely pointed terminus with a finger-like projection. Phylogenetic analyses based on the nearly full length small subunit ribosomal DNA sequences of Meloidoderita salina sp. n. revealed a close relationship of the new species with Sphaeronema alni Turkina & Chizhov, 1986 and placed these two species sister to the rest of Criconematina. [ABSTRACT FROM AUTHOR]

Radopholus arabocoffeae sp. n., a new nematode pathogenic on Coffea arabica cv. Catimor, is described from Vietnam. Females of R. arabocoffeae sp. n. are characterised by the broad amphidial apertures with prominent margins. Males are characterised by the bursa extending to one third, rarely middle, of the tail. The new species belongs to the group of species with a long tail in the female. Radopholus arabocoffeae sp. n. is easily distinguished from R. similis by the bursa reaching to only one third of the tail vs extending to the tail terminus. Radopholus arabocoffeae sp. n. is differentiated from R. bridgei by the lateral field having three bands of equal width (vs middle one narrower than others), lateral field completely areolated over whole body vs not areolated except irregularly in neck and tail, hemizonid distinct vs indistinct, four lateral field incisures terminating far behind phasmid vs three incisures terminating at or just behind phasmid, lateral lines fusing at two thirds of tail vs fusing at one third of tail, longer spicule length (18-21 vs 15.5-18.0 μm), and male bursa usually extending to only one third of tail vs mid tail. Radopholus arabocoffeae sp. n. differs from R. colbrani by the rod-like vs round sperm, spicule length (18-21 vs 13-16 μm), tail length to stylet ratio (4.1-4.9 vs more than 5.1) and presence vs absence of a bursa. Radopholus arabocoffeae sp. n. differs from R. duriophilus by the rod-like vs kidney-shaped sperm. Males further differ from R. duriophilus by shorter stylet length (8.2-11.6 vs 11.5-15 μm), smaller distance between dorsal pharyngeal gland orifice and stylet base (1.7-3.4 vs 4-9.5 μm), shorter hyaline tail (2.6-3.4 vs 4-9.5 μm), and bursa extending to one third of tail vs mid-tail. Female R. arabocoffeae sp. n. differ from R. duriophilus by the broad amphidial aperture with prominent margin present vs absent. Males of R. arabocoffeae sp. n. differ from R. musicola by the rudimentary and amalgamated stylet base (vs with knobs), and inner lateral lines fusing at two thirds of the tail vs just posterior to the phasmid. The high level of ITS-rDNA sequence divergence of R. arabocoffeae sp. n. from other Radopholus spp. and the presence of nucleotide autapomorphies support a separate specific status of this new species. On carrot disks, the two species reproduced from 15-30°C; optimum reproduction occurring at 28°C. The reproductive capacity of R. duriophilus was higher than that of R. arabocoffeae sp. n. Radopholus duriophilus reproduced from single juveniles; R. arabocoffeae sp. n. did not. The correlation between initial densities of Pratylenchus coffeae, R. duriophilus and R. arabocoffeae sp. n. and the weight of C. arabica cv. Catimor fitted the Seinhorst model Y = ym for Pi ≥ T, and Y = ym m + ym(1–m)z(Pi–T). Coffea arabica cv. Catimor was very susceptible for to all three nematode species tested, but especially so to R. arabocoffeae sp. n. The reproductive capacity of R. arabocoffeae sp. n. on C. arabica cv. Catimor was higher than P. coffeae or R. duriophilus. [ABSTRACT FROM AUTHOR]

A population of a root-knot nematode species was isolated from Zoysia japonica in a turf nursery in Israel. Measurements and morphology of the second-stage juveniles and adult females, including perineal pattern, indicated this nematode to be Meloidogyne marylandi. In addition, esterase (Est) and malate dehydrogenase (Mdh) isozymes were studied for the first time for this species which is shown to be characterised by VS1 Est band and a N1c Mdh pattern. Host range tests showed that the turf grasses Stenotaphrum secundatum, Dactyloctenium australe and Paspalum vaginatum, corn (Zea mays) and oat (Avena sativa) were non-hosts or resistant. Kikuyu grass (Pennisetum clandestinum), wheat (Triticum aestivum), barley (Hordeum vulgare), bristle oat (Avena strigosa), Siberian millet (Echinochloa frumentaceae) and pearl millet (Pennisetum glaucum) were susceptible to the nematode. The second-stage juveniles of M. marylandi penetrated the elongation zone of wheat roots but did not reach the meristematic zone and settled with their anterior end toward the root tip. This contrasted with M. javanica or M. incognita which migrated to the meristematic zone, and turned around with their anterior toward the root base. Meloidogyne marylandi juveniles induced giant cells from vascular parenchyma cells and caused no or only small galls on the roots. [ABSTRACT FROM AUTHOR]

An overview is presented of all plant parasitic and soil inhabiting nematodes found in Slovenia. Most of the nearly 50 records, representing 115 nematode genera and 112 different species, have been published in national journals or technical reports and are therefore not directly available. These records include plant- and animal-parasitic nematodes, free-living nematodes and marine nematodes. The greater part of them was isolated from agricultural areas, while others were found in natural areas such as the Adriatic sea and caves. [ABSTRACT FROM AUTHOR]

Gonads from living young females, representing 23 different species, were extracted to study the cellular structure of the female genital structure within the Meloidogyninae and Heteroderinae. All genera studied can be characterised by their cellular spermatheca morphology. Within Meloidogyne a spherical spermatheca is found with lobe-like protruding cells, most species having 16 to 18 spermatheca cells with interlaced cell boundaries while M. microtyla and M. ichinohei have more spermatheca cells with different cell boundaries. Heterodera and Globodera reveal a comparable gonad structure. The spermatheca cells of Heterodera are columnar and arranged in a restricted number of rows, whereas in Globodera the spermatheca cells are squarish to rounded, depending on the species. The gonad morphology of Afenestrata koreana is clearly different from what would be expected based on the related genera Globodera and Heterodera. The apparently simplest genital system was found in Meloidodera floridensis where the uterus has a limited number of cells. In the other genera studied a large and variable cell number was found. [ABSTRACT FROM AUTHOR]

Additional detailed morphological information on features of the marine nematode Epsilonema pustulatum is presented for the first time. Lip structure, amphideal fovea, cuticular appendages (setae, spines, anal and copulatory thorns), annules and vacuoles, body inversion, setae ambulatoriae region, vulva, cloaca/anus and tail end are SEM studied and illustrated. Additionally, E. pustulatum (from Spain, Italy and Lebanon) is compared with other former Bathyepsilonema species. E. anulosum (Verschelde & Vincx, 1992) is proposed as a junior synonym of E. pustulatum. Observations au microscope électronique à balayage sur le nématode marin côtier Epsilonema pustulatum (Gerlach, 1952) Lorenzen, 1973 (Nematoda: Epsilonematidae) - Des données morphologiques nouvelles concernant le nématode marin Epsilonema pustulatum sont présentées pour la première fois. Sont étudiés en microscopie électronique à balayage et illustrés des caractères tels que la structure labiale, les fovea amphidiales, les appendices cuticulaires (sétes, épines du corps, épines anales et copulatoires), anneaux et vacuoles, courbure du corps, région des sétes ambulatoires, vulve, cloaque/anus et extrémité de la queue. De plus, E. pustulatum (provenant d'Espagne, Italie et Liban) est comparé avec d'autres espèces auparavant placées dans le genre Bathyepsilonema. E. anulosum (Verschelde & Vincx, 1992) est proposé comme synonyme mineur d'E. pustulatum. [ABSTRACT FROM AUTHOR]

Reniform nematodes of the genus Rotylenchulus are semi-endoparasites of numerous herbaceous and woody plant roots that occur largely in regions with temperate, subtropical, and tropical climates. In this study, we compared 12 populations of Rotylenchulusborealis and 16 populations of Rotylenchulusmacrosoma, including paratypes deposited in nematode collections, confirming that morphological characters between both nematode species do not support their separation. In addition, analysis of molecular markers using nuclear ribosomal DNA (28S, ITS1) and mitochondrial DNA (coxI) genes, as well as phylogenetic approaches, confirmed the synonymy of R. macrosoma with R. borealis. This study also demonstrated that R. borealis (= macrosoma) from Israel has two distinct rRNA gene types in the genome, specifically the two types of D2-D3 (A and B). We provide a global geographical distribution of the genus Rotylenchulus. The two major pathogenic species (Rotylenchulusreniformis and Rotylenchulusparvus) showed their close relationship with warmer areas with high annual mean temperature, maximum temperature of the warmest month, and minimum temperature of the coldest month. The present study confirms the extraordinary morphological and molecular diversity of R. borealis in Europe, Africa, and the Middle East and comprises a paradigmatic example of remarkable flexibility of ecological requirements within reniform nematodes. [ABSTRACT FROM AUTHOR]

Discusses the routine identification of the Pratylenchus crenatus (P. crenatus) Loof nematoda. Description of the secretory-excretory duct of the nematode; How the character of the P. crenatus species can be useful to the examination of Pratylenchus.

Provides information on the parthenogenetic nematode Pratylenchus crenatus where males have never been found with certainty. Morphological characteristics of the male nematode; Use of a light microscope using differential interference contrast; Important diagnostic features confirming that the male belongs to Pratylenchus crenatus.