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Plant-parasitic nematodes (PPNs) are significant pests that result in considerable economic losses in global crop production. Due to the high toxicity of chemical nematicides, there is a need to develop new strategies for nematode control. In this context, nematophagous fungi may offer a viable option for biological control. Two fungal strains (GUCC2212 and GUCC2232) were isolated from cysts of Globodera sp., identified as Neocosmospora stercicola. The fungal filtrates of the strains were evaluated for their nematicidal activity against three species of PPNs: Aphelenchoides besseyi, Bursaphelenchus xylophilus and Ditylenchus destructor. The fermentation filtrates of two strains exhibited substantial toxicity towards the evaluated nematodes, with mortality rates reaching up to 100% within 72 h. Concurrently, N. stercicola also demonstrated predatory and parasitic behavior. The eggs of Globodera sp. were parasitized by the two strains. N. stercicola represents a newly recorded species in China and a novel nematophagous species. In conclusion, the two strains of N. stercicola show promise as biocontrol agents for PPNs management.

A new cyst-forming nematode, Heterodera microulae sp. n., was isolated from the roots and rhizosphere soil of Microula sikkimensis in China. Morphologically, the new species is characterized by lemon-shaped body with an extruded neck and obtuse vulval cone. The vulval cone of the new species appeared to be ambifenestrate without bullae and a weak underbridge. The second-stage juveniles have a longer body length with four lateral lines, strong stylets with rounded and flat stylet knobs, tail with a comparatively longer hyaline area, and a sharp terminus. The phylogenetic analyses based on ITS-rDNA, D2-D3 of 28S rDNA, and COI sequences revealed that the new species formed a separate clade from other Heterodera species in Goettingiana group, which further support the unique status of H. microulae sp. n. Therefore, it is described herein as a new species of genus Heterodera; additionally, the present study provided the first record of Goettingiana group in Gansu Province, China.

A new cyst-forming nematode, Cactodera tianzhuensis n. sp. was isolated from the rhizosphere soil of Polygonum viviparum L. in Tianzhu county, China. Morphologically, the new species is characterized by lemon-shaped or rounded cysts that have protruding necks and vulval cones. The vulval cone of the new species appeared to be circumfenestrate without bullae and underbridge, vulval denticle present and anus distinct. Second-stage juveniles are vermiform, stylet well-developed with the rounded stylet knobs to slightly concave anteriorly. Lateral field with four incisures. Tail gradually tapering to a finely rounded terminus with a length of ca 54 (47–59) µm, outline of hyaline portion is V-shaped or U-shaped. Egg shells without visible markings or punctations. The phylogenetic analyses based on ITS-rDNA, D2-D3 of 28S-rDNA clearly revealed that the new species formed a separate clade from other Cactodera species, which further support the unique status of C. tianzhuensis n. sp. Therefore, it is described herein as a new species of the genus Cactodera.

During a survey for the cyst nematodes (Heterodera elachista) from May to June of 2011, cyst nematodes were detected in hilly rice fields in five counties (Changsha, Pingjiang, Hengdong, Shaoyang, and Xiangxiang) of Hunan Province, China. Cyst nematodes obtained from soil samples and harvested rice root samples at these five locations had uniform morphological and molecular characteristics. Cysts (n = 20) had the following characteristics: spherical to lemon shaped, vulval cone ambifenestrate, vulval bridge narrow, medium sized underbridge, with a few dark brown bullae, body length (not including the neck) ranging from 354 to 586 μm (mean = 438.9 μm, st. dev. = 63.7); body width ranged from 283 to 495 μm (354.5, 60.1); fenestrate length of 30 to 50 μm (37.4, 5.0) and width of 25 to 47.5 μm (35.1, 7.1); underbridge length from 70 to 95 μm (83.4, 8.2); and vulval slit length from 30.3 to 55.5 μm (40.3, 9.1). J2 (n = 20) had the following characteristics: body length ranging from 404 to 525 μm (mean of 461.6 μm, st. dev. = 34.5); stylet length from 20 to 25 μm (22.5, 1.1) with rounded knob; tail length of 60 to 87.5 μm (67.3, 6.9); and hyaline terminal tail ranged from 30 to 50 μm (37.5, 6.4); lateral field with three lines. The mean and range of J2 were longer than those reported for H. elachista by Nobbs et al. (1) and Tanha et al. (4), but other morphological character values were within the range of those reported (4). DNA from a single cyst was extracted, the rDNA-internal transcribed spacer (ITS) and D2/D3 fragments of the 28S RNA were amplified with universal primers TW81 and AB28, D2A and D3B, respectively. Five ITS sequences (JN202913, JN202914, JN202915, JN202916, and JN202917) and five D2/D3 sequences (JN202918, JN202919, JN202920, JN202921, and JN202922) from nematode samples collected in Changsha, Hengdong, Shaoyang, Pingjiang, and Xiangxiang, respectively, were submitted to GenBank. These ITS sequences were remarkably similar to each other and exhibited 98.6 to 99.3% similarity with that of H. elachista isolate from Iran (AF498391), and 98.8 to 99.4% similarity with that of H. elachista isolates from Ningxia Province, China (HM560778 and HM560779). The D2/D3 sequences exhibited 99.7 to 100% similarity with that of H. elachista isolates from Ningxia Province, China (HM560842 and HM560843). These characteristics indicated that the five populations were H. elachista belonging to the ‘cyperi’ group (1,2). In glasshouse evaluations of the pathogenicity of these isolates, 500 second-stage juveniles were inoculated onto five 20-day-old seedlings of rice (Weiyou No.227) in 4.5-cm diameter 30-cm high tubes with six replicates. After 8 weeks, stunting and reduction of leaf length were observed and cysts were extracted from dried soil of each tube using sieves. Brown cysts (92 to 204) and white females (14 to 40) were obtained from inoculated rice from each tube. H. elachista can decrease yield by 7 to 19% and has the most severe impact during the later stages of plant growth (3). H. elachista has been previously identified from rice fields in Japan and Iran (3). To our knowledge, this is the first report of H. elachista on rice in Hunan Province, China. References: (1) J. M. Nobbs et al. Fundam. Appl. Nematol. 15:551, 1992. (2) S. A. Subbotin et al. Mol. Phylogenet. Evol. 21:1, 2001. (3) S. A. Subbotin et al. Systematics of Cyst Nematodes (Nematoda: Heteroderinae). Volume 8 Part B. Brill, Leiden, the Netherlands, 2010. (4) M. Z. Tanha et al. Nematology 5:99, 2003.

Data of the current knowledge about the number of incisures in the lateral fields of secondstage juveniles and males, shape of phasmids and tip of spicules of the 158 recognised species in the 19 genera in the family Heteroderidae are reviewed and compiled. All characters are of diagnostic value in distinguishing genera and intrageneric species groups, but more detailed studies are needed. Differences in the number of incisures or in the size of phasmids among species of Cryphodera, Meloidodera and Atalodera are considered as an indication of paraphyly. In agreement with results of molecular analyses, three additional species groups are proposed for Heterodera species with Poales as hosts (Cardiolata, Koreana and Orientalis groups), and in Globodera designation of Rostochiensis, Millefolii and Zelandica groups. Information on host ranges and host reaction to parasitism has great relevance for the study of phylogenetic relationships and estimation of the age of taxa. Evaluation of biogeographical data restricted to ‘natural’ occurrence as well as consideration of geological and palaeoclimatic events are essential for the recovery of putative ancestral areas of origin of taxa. Heteroderid populations tentatively identified as Meloidodera, Hylonema and Sarisodera are briefly characterised from Africa (the first two genera) and Vietnam (the third genus). Other populations of unidentified species or representatives of still unknown genera are reported from Borneo, the Canary Islands, the Dominican Republic, New Zealand, Thailand, Tunisia and Vietnam.

Heterodera hainanensis n. sp. is described and illustrated from bamboo (Phyllostachys pubescens) based on morphology and molecular analyses of rRNA D2D3 region of LSU and ITS. This new species belongs to the Afenestrata group and is characterised by lemon-shaped cyst with prominent vulval cone and vulval cone without fenestration and bullae but with weak and furcate underbridge. The second-stage juvenile (J2) has two lip annuli, a 15.8-17.5 μm long stylet with rounded knobs sloping slightly posteriorly, three incisures in the lateral field and a conical tail with hyaline portion forming 52.3-71.1% of the tail length. Heterodera hainanensis n. sp. most closely resembles species in the Afenestrata group but is distinguished from these species by a number of characters, including cyst shape and size, the presence of an underbridge, vulval slit length, J2 stylet length, stylet knobs shape, incisure number and lip annule number. Molecular analysis reveals that this species has unique LSU D2D3 and ITS rRNA sequences and RFLP-ITS-rRNA profiles, and it is most closest to H. koreana in dendrograms inferred from both markers. A key to all species of the Afenestrata group is presented.

The cellular morphology of the gonoduct of six Pratylenchus species, three Pratylenchoides species, Radopholus similis, Zygotylenchus guevarai, Hirschmanniella loofi and Nacobbus aberrans was revealed by dissection and light microscopy. Except for Nacobbus aberrans, all studied species show an overall similarity in gonoduct construction, i.e., an ovary often ending with a ring of cells, an oviduct formed from two rows of four cells and a 12-celled spermatheca followed by a tricolumella containing 16-24 cells. Pratylenchoides magnicauda and Z. guevarai did not diverge from the other Pratylenchidae in this respect, although their gonoduct differs from that of Amplimerlinius and Meloidogyne, both formerly postulated as related genera. The spermatheca structure observed in N. aberrans has not been reported elsewhere in the Nematoda, although the uterus is similar to that reported within the Heteroderinae and Meloidogyninae and the uterus comprises more than 300 cells, enlarging from a tricolumella to a polycolumella. Transmission electron microscopy of Z. guevarai revealed details of the cytoplasmatic contact between epithelial cells and the germ cells; a finger-like ovarian wall cell extension was found penetrating the oocyte. The oviduct lacks a preformed lumen and comprises eight cells with highly plicated cell membranes. The spermatheca is constructed from flattened wall cells and is followed by columnar uterus cells where evidence of eggshell formation was demonstrated.

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.

The first comparative study of head patterns in tylenchs was that of Sher & Bell (1975). De Grisse (1911) and Coomans & De Grisse (1981) srudied rhe underlying nervous system. The new information added since then is reviewed in this paper to see if the various patterns are characteristic of higher groupings (e.,9. families) within the Tylenchoidea. Therefore I used published and unpublished scanning electron micrographs (sEM) to produce schematized drawings. Comparing the photographs it was obvious that variation was found in the expression of pattems and sensilla. The schematized drawings give the maximum infbrmation obtained: e.g. whatever sensillum, distinct on a single photograph of a species or genus, was added on the drawing. In contrast to other nematodes there are no distinct lips in tylenchs. The head is an amalgamated lip region, internally strengthened by a cephalic framework and often including annuli, perhaps derived from ones formerly part of the body. The head can be continuous with the body, or variously offset but is always small to very small and unspectacular. It bears the mouth opening, which is nlinute and situated apically and centrally. There are two consecutive openings: the mouth opening seen at the outside is the prestoma opening: small, rounded to oval in Tylenchoidea and Aphelenchina, dorso-ventral slit to I-shaped slit in Criconematoidea. The stoma opening is found less than a micrometer to the

The fine structure of sperm of Heterodera schachtii and Punctodera chalcoensis demonstrates a high degree of interspecific morphological and developmental diversity, particularly in comparison with previously examined Heteroderinae that develop cysts, including Globodera tabacum, as well as out-groups that lack cysts, including species of Verutus, Meloidodera, and Ekphymatodera. Sperm of P. chalcoensis are much smaller and have fewer filopodia than those of species of Heterodera and Globodera. However, the distribution of filopodia on only part of the body, the smooth surface of the filopodia, and the presence of cortical microtubules are traits shared by the three genera with cysts. Unique features shared by P. chalcoensis and Globodera species include the short persistence of fibrous bodies after spermiogenesis and the lack of sperm polarization in the female genital tract. These traits are absent in Heterodera species. Conversely, chromatin remains unchanged with respect to condensation during sperm development in P. chalcoensis and species of Heterodera but not in Globodera. Patterns of evolution of sperm may be useful for testing hypotheses of the phylogeny of Heteroderinae, but the diversity is so great that character coding will be required for a large number of representative species.

The fine structure of sperm of one representative species each of Verutus and Meloidodera was compared through development from the pre-adult male as a starting point for the discovery of new phylogenetically informative characters for Heteroderinae. Males of both V. volvingentis and M. floridensis have a single tubular genital tract, including a telogonic testis and a wall consisting of a single layer of epithelial cells enclosing conspicuous vesicles believed to be secretory. As in other nematodes, the sperm lack a flagellum, acrosome, and axoneme, and the nuclear envelope is lost during spermatogenesis. Nevertheless, the sperm are highly divergent between the two representative species. Those of V. volvingentis are about twice the size of those of M. floridensis, and the former can also be distinguished from the latter by the asymmetrical distribution of their filopodia and the relative lack of change in condensation of chromatin after insemination. In addition, fibrous bodies are less persistent in sperm of V. volvingentis than in those of M. floridensis. Since both representative species lack cortical microtubules, which are present in other Heteroderinae, examination of additional out-groups may support this loss as a synapomorphy between Verutus and Meloidodera.

Evolution and diversity of Heteroderinae are of special interest because worldwide the subfamily includes some of the most destructive plant-parasitic nematodes of agriculture. Some Heteroderinae form resistant cysts which may protect eggs in the soil for years. Other Heteroderinae lack a cyst, but typically these forms are not a threat to agriculture. Seventeen genera and more than one hundred species are recognized (Table I). Phylogenetic analysis of this diverse group is important to a sound taxon­ omy of Heteroderinae. Because a natural classification that reflects genealogi­ cal history has predictive value it will readily adapt to accommodate newly discovered taxa and characters. Classifications that attempt to reflect evolu­ tionary history have a basis for stability not inherent to artificial classifica­ tions. Heteroderinae may provide a useful metazoan model for interpreting evolu­ tion in other small invertebrates. Global knowledge of extant genera and species of Heteroderinae is undoubtedly more complete, and living specimens of most species are more readily available than specimens of species of invertebrate groups often considered to be of lesser economic importance

The female body wall cuticle of Bellodera utahensis and Ekphymatodera thomasoni (Heteroderinae) has an external sub-crystalline layer and four concentric layers, A, B, C, and D. Surface striae of the cuticle of B. utahensis are transverse, whereas those of E. thomasoni are longitudinal. The surface patterns are reflected in the A layer, which is thickest in the elevated regions between striae. The B layer consists of vertical columns and is continuous in young females but is broken into discontinuous patches as the female increases in girth. The C layer and adjacent D layer tend to merge at an intermediate zone in B. utahensis and E. thomasoni. The D layer is composed of fibrils about 31 nm in diameter arranged in a helicoidal pattern. An E layer adjacent to the hypodermis is present only in B. utahensis. The D layer is not resolved in newly molted females of B. utahensis, contrary to E. thomasoni. The presence of a D layer is a phylogenetic character shared with most other Sarisoderini. Although further investigation of Rhizonema and Hylonema is needed, existing knowledge of the body wall cuticle in females strengthens hypotheses of the monophyly of Sarisoderini.

Taxonomic schemes for the Heteroderinae Filip'ev & Schuurmans Stekhoven, 1941, sensu Luc et al., (1988) have been unstable due to the large number of genera and the paucity of known reliable characters. Reliable characters are essential when using phylogenetic inference in developing a natural classification. Morphological and developmental studies using light, scanning and transmission electron microscopy have revealed the new characters of host response, en face patterns, phasmid structure and female cuticular layers. These techniques also gave us insight into the homoplasy and polarity of many characters, revealed previously undetected character states and clarified misinterpreted character states. A matrix with the 19 most reliable characters is proposed for 20 operational taxonomic units (OTUs) and we employ this matrix for comparing computer generated phylogenetic analyses of the PHYLIP and PAUP packages. PAUP was deemed the more reliable parsimony algorithm for phylogenetic analysis of the Heteroderinae (Fink, 1986; Platnick, 1987). Monophyly of Atalodera + Sherodera + Thecavermiculatus (tribe Ataloderini), and Cactodera + Heterodera + Afenestrata, as well as Punctodera + Globodera + Dolichodera is supported by both programs. Most importantly, analyses strongly support monophyly of all cyst-forming genera (tribe Heteroderini) contrary to previous hypotheses of repeated evolution of the cyst (Wouts, 1985). In addition, monophyly of the Heteroderini with the Ataloderini is demonstrated. PAUP indicates monophyly of Sarisodera + Rhizonema + Bellodera + Hylonema and Ekphymatodera (tribe Sarisoderini new rank). Monophyly of the Sarisoderini was at first only weakly supported, but, subsequently, the reduced width of the submedial lips of second stage juveniles and males was recognized as a synapomorphy which strengthened subsequent PAUP trees and monophyly of the tribe. The present study rejects as paraphyletic or polyphyletic several previously proposed combinations, including Thecavermiculatus sequoiae (versus Rhizonema sequoiae), Sarisodera africana (versus Afenestrata africana), Dolichodera andinus (versus Thecavermiculatus andinus). The question whether T. andinus is a distinct genus, was not resolved due to insufficient data. PAUP supports our previous observations that Cactodera betulae is intermediate in a transformation series between other Cactodera and Heterodera: it also indicates these species as bring monophyletic with Heterodera + Afenestrata, but not with other Cactodera. Although these phylogenetic analyses strongly support some relationships, they indicate unresolved alternative hypotheses for others. Meloidodera (tribe Meloidoderini) and Cryphodera (tribe Cryphoderini) must be investigated for consideration of a possible synapomorphy not included in the present data matrix. Future studies are proposed to more clearly define the monophyly of the Heteroderini, as well as the Sarisoderini. Tests are also proposed to clarify questions of the monophyly of Verutus (tribe Verutini new rank) with the Heteroderinae versus other Tylenchida.

The ITS1, ITS2, and 5.8S gene sequences of nuclear ribosomal DNA from 40 taxa of the family Heteroderidae (including the genera Afenestrata, Cactodera, Heterodera, Globodera, Punctodera, Meloidodera, Cryphodera, and Thecavermiculatus) were sequenced and analyzed. The ITS regions displayed high levels of sequence divergence within Heteroderinae and compared to outgroup taxa. Unlike recent findings in root knot nematodes, ITS sequence polymorphism does not appear to complicate phylogenetic analysis of cyst nematodes. Phylogenetic analyses with maximum-parsimony, minimum-evolution, and maximum-likelihood methods were performed with a range of computer alignments, including elision and culled alignments. All multiple alignments and phylogenetic methods yielded similar basic structure for phylogenetic relationships of Heteroderidae. The cyst-forming nematodes are represented by six main clades corresponding to morphological characters and host specialization, with certain clades assuming different positions depending on alignment procedure and/or method of phylogenetic inference. Hypotheses of monophyly of Punctoderinae and Heteroderinae are, respectively, strongly and moderately supported by the ITS data across most alignments. Close relationships were revealed between the Avenae and the Sacchari groups and between the Humuli group and the species H. salixophila within Heteroderinae. The Goettingiana group occupies a basal position within this subfamily. The validity of the genera Afenestrata and Bidera was tested and is discussed based on molecular data. We conclude that ITS sequence data are appropriate for studies of relationships within the different species groups and less so for recovery of more ancient speciations within Heteroderidae.

Amplified fragment length polymorphism (AFLP) was used to obtain information on the within-species geneticvariability of the tobacco cyst – nematode (TCN) complex. AFLP was found to be well suited to this type ofstudy. The current classification of TCN was confirmed. Results indicate that the Globodera tabacum solanacearumgroup, believed to be restricted to the U.S.A., also occurs in Mexico. The within-species variability of TCN is considerable.Populations from Mexico may form a new subgroup. AFLP group-specific markers were identified for two ofthe TCN subgroups: Globodera tabacum tabacum and Globodera tabacum solanacearum.; La technique dite de l'AFLP a été utilisée sur les nématodes à kystes du tabac (TCN) afin d'acquérir des connaissances sur leur polymorphisme moléculaire intra-spécifique. L'efficience de la technique AFLP pour ce type d'études a été réaffirmée. La classification intra-spécifique des TCN communément admise est confirmée. Les résultats indiquent que le groupe Globodera tabacum solanacearum, jusqu'à présent décrit uniquement aux États-Unis, existe également au Mexique. Une variabilité intra-spécifique élargie est mise en évidence au sein des TCN. Des populations originaires du Mexique pourraient former un nouveau sous-groupe. Des marqueurs AFLP spécifiques pour deux des sous-groupes du complexe des TCN, Globodera tabacum tabacum et Globodera tabacum solanacearum, sont mis en évidence.Mots clés : Heteroderinae, classification, marqueurs, diversité génétique, distribution géographique.

A non cyst-forming heteroderid nematode, Cryphodera brinkmani n. sp., is described and illustrated from the roots of Pinus thunbergii Parlatore from Japan; this new species is characterised by globose female with annulated cuticle and curved projecting neck; stylet 41.5 mum long, with rounded knobs, set off from the shaft; excretory pore located 120 to 157 mum from the anterior end, vulva terminal, with a vulva-anus distance of 49 mum and slightly protruding vulval lips, vulva-anus area ranging from flat to concave, subcrystalline layer present, eggs retained in the body; males rare, with head region set off, two lip annules present, stylet 37.5 mum long, rounded knobs set off, anteriorly slightly pointed, lateral field with three incisures, areolated; second-stage juvenile body 493 mum long, head region set off, four cephalic annuli present, stylet 33.5 mum long, with large anteriorly concave knobs, set off from the shaft, tail 70 mum, tapering towards a pointed hyaline tail terminus of 37 mum in length, areolated lateral field with three incisures, phasmids with a lens-like structure located 6 to 10 mum posterior to the anus. A key for the Cryphodera species is proposed. Description de Cryphodera brinkmani n. sp. (Nematoda: Heteroderidae) parasite de Pinus thunbergii Parlatore au Japon et clef des especes du genre Cryphodera Colbran, 1966 - Un nematode Heteroderide ne formant pas de kyste, Cryphodera brinkmani n. sp., provenant des racines de Pinus thunbergii au Japon, est decrit et illustre; cette nouvelle espece est caracterisee par les femelles globuleuses a cuticule annelee et extremite anterieure courbe, stylet long de 41,5 mum a boutons basaux arrondis bien individualises, pore excreteur situe a 120-157 mum de l'extremite anterieure, vulve terminale (distance vulve-anus 49 mum) et levres vulvaires legerement saillantes, aire perineale plate a concave, presence d'une couche subcristalline, oeufs retenus dans le corps. Les males, rares, ont une region labiale separee du reste du corps, deux anneaux cephaliques, un stylet long de 37,5 mum avec boutons basaux arrondis, bien individualises et legerement pointus anterieurement, des champs lateraux avec trois incisures, areoles. Les juveniles de deuxieme stade, longs de 493 mum, ont une region cephalique separee avec quatre anneaux, un stylet long de 33,5 mum avec des boutons basaux de grande taille, bien individualises et a face anterieure concave, une queue longue de 70 mum, amincie a extremite effilee avec une zone hyaline longue de 37 mum, des champs lateraux marques de trois incisures et areoles, des phasmides a structure lenticulaire situees 6-10 mum posterieurement a l'anus. Une clef pour la determination des especes du genre Cryphodera est proposee.

Cyst nematodes (Heteroderinae) comprise at least 17 different genera and include many important species of plant-parasitic nematodes that interfere with agricultural production (Sasser and Freckman, 1987; Baldwin and Mundo-Ocampo, 1991). Infection by cyst nematodes on numerous host plants species around the world causes significant yield losses. Major species of cyst nematodes, such as Heterodera schachtii Schmidt, 1871 on sugar beet, H. glycines Ichinohe, 1952 on soybean, and Globodera rostochiensis (Wollenweber, 1923) Behrens, 1975 and G. pallida (Stone, 1973) Behrens, 1975 on potato, etc., remain of major economic importance worldwide. These costly pests have been the focus of numerous research on various aspects of host-parasite relationships (Wyss and Zunke, 1986a, b).

The cyst nematodes, subfamily Heteroderinae (sensu Luc, Maggenti and Fortuner, 1988) are sedentary endoparasites of plant roots in three juvenile stages, and sedentary semiendoparasites in the adult female stage. Adult males exit the root and do not feed. The female body forms a hardened cyst that encases viable eggs (Luc, Maggenti and Fortuner, 1988). Most species of cyst nematodes have a narrow host range, which creates some unique possibilities for crop rotation. However, the adaptive disadvantage of a narrow host range is often offset by long survival in the absence of a food source, adding complexity to the design of management strategies. While a few species are well-known for their devastating effect on crops, approximately 50% of the known species are exclusively parasites of grasses and sedges (Table 10.1).

The family Heteroderidae of plant parasitic nematodes contains the cyst-forming species within the sub-family Heteroderinae, within which the numbers of genera (not all cyst-forming) and species described have increased greatly over the last five decades. When Franklin (1951) published her book on “The cyst-forming species of Heterodera”, cyst nematodes were already a major concern and were known to cause serious yield losses in important food crops such as potatoes, cereals, brassicas, tomatoes and sugar beet. The genus Heterodera Schmidt 1871 was, at that time, considered to be largely temperate, with about 12 species. Today, 67 valid species are recognized in the genus Heterodera alone (Table 1.1). After many studies and revisions in classification (Mulvey, 1972; Stone, 1977; Luc, Maggenti and Fortuner, 1988; Baldwin and Schouest, 1990), the specific characters of many other species that were once members of the genus Heterodera have been accommodated in new genera. These new genera of cyst-forming species are Globodera, Punctodera, Cactodera, Afenestrata and Dolichodera, which are listed with the species they contain in Table 1.2. The cyst-forming genera of the Heteroderinae seem, in general, to have hosts within particular plant families. For instance, the Poaceae support many species of Heterodera and Punctodera. On the other hand, there are examples of unusual host specificity within genera, such as Cactodera betulae, found normally on birch and occasionally alder whilst other species of Cactodera are found on members of the Cactaceae, Amaranthaceae and Chenopodiaceae.

Heterodera guangdongensis n. sp. is described from bamboo (Phyllostachys pubescens Mazel) based on morphology and molecular analyses of rRNA D2D3 expansion domains of large subunit (LSU D2D3) and internal transcribed spacer (ITS) sequences. This new species can be classified in the Cyperi group. Cysts are characterized by a prominent, ambifenestrate vulval cone with weak underbridge, a vulva-anus distance of 28.9–35.9 μm and a vulval slit of 31.1–41.0 μm, but without bullae. Females are characterized by a 25.1–27.6 μm stylet with rounded knobs sloping slightly posteriorly. Males are characterized by a 21.5–23.0 μm stylet with knobs slightly projecting or flat anteriorly, lateral field with four lines, and a 22.0–26.0 μm spicule with bifurcate tip. Second-stage juveniles are characterized by a 19.3–21.3 stylet with slightly projecting or anteriorly flattened knobs, lateral field with three lines, a 41.7–61.3 μm tail with finely rounded terminus and hyaline portion forming 43.0–57.1% of the tail length. Molecular analyses show that the species has unique D2D3 and ITS rRNA sequences and RFLP-ITS-rRNA profiles.

During a survey for cyst nematodes from August to September 2011, nearly 15% of cactus (Cereus jamacaru) plants exhibited yellowing and wilting symptoms in greenhouses from Shenyang Botanical Garden, Liaoning Province, China. Cysts (averaging 50 per 100 g of samples) were detected by the sieving-decanting method on the roots and in rhizospheric soil. Second stage juveniles and eggs were isolated directly from cysts. Cysts, juveniles, and eggs were identified by morphology. Cysts (n = 12) were rounded to lemon-shaped with a protruding neck and vulva. The cyst wall had a zig-zag pattern. The vulval cone was circumfenestrate without underbridge and bullae but generally with vulval denticles. The cysts were characterized by body length excluding neck (range = 399.5 to 622.0 μm, mean = 524.9), body width (300.4 to 469.9 μm, 383.4), length to width ratio (1.1 to 1.7, 1.4), neck length (41.0 to 130.9 μm, 61.5) and width (55.0 to 98.7 μm, 76), and circumfenestral diameter length (24.6 to 30.2 μm, 28.4). Measurements of second-stage juveniles (n = 20) included length of body (range = 467.3 to 542.5 μm, mean = 513.8), stylet (23.0 to 25.8 μm, 24.6) with knobs rounded to slightly projecting anteriorly and concave on anterior surface, tail (45.9 to 59.5 μm, 52.2), and hyaline tail terminal (16.3 to 23.2 μm, 19.1). Eggs (n = 20) had heavy punctations on the shell surface. All morphological data and characteristics were consistent with Cactodera cacti (3). Molecular evidence confirmed the identification. DNA from a single cyst was extracted by using the protocol described by Subbotin et al. (2), the rDNA-internal transcribed spacer (ITS) and D2-D3 fragments of the 28S rDNA were amplified with universal primers TW81 (5′-GTTTCCGTAGGTGAACCTGC-3′) and AB28 (5′-ATATGCTTAAGTTCAGCGGGT-3′), D2A(5′-ACAAGTACCGTGAGGGAAAGTTG-3′) and D3B(5′-TCGGAAGGAACCAGCTACTA-3′), respectively. The ITS PCR product was digested with eight restriction enzymes (AluI, AvaI, Bsh1236I, BsuRI, CfoI, MvaI, PstI, and RsaI) to obtain restriction fragment length polymorphism profiles (4). The ITS and D2D3 sequences were cloned and assayed using an ABI-PRISM 3730 Genetic Analyzer (Applied Sangon, Shanghai, China) and were subjected to a database search using BLAST (National Centre for Biotechnology Information). The 980-bp ITS sequence exhibited 99% similarity with that of a C. cacti isolate from Iran (GenBank Accession No. AF498393.1) and the 787-bp D2D3 sequence exhibited 99% similarity with a C. cacti isolate from Germany (GenBank Accession No. DQ328702.1). Cactus cyst nematode has been mainly reported on ornamental plants of the family Cactaceae grown in greenhouses. Infested plants become reddish brown to yellow in color, wilted, stunted, with reduced flower production and shortening flower period. With high population densities of C. cacti, death of plants may occur (1). To the best of our knowledge, this is the first report of C. cacti in northern China. References: (1) R. P. Esser. Division of Plant Industry, 197:3, 1992. (2) S. A. Subbotin et al. Nematology, 2:153, 2000. (3) S. A. Subbotin et al. Systematics of Cyst Nematodes (Nematoda: Heteroderinae). Volume 8 Part A. Brill, Leiden, the Netherlands, 2010. (4) M. Z. Tanha et al. Nematology, 5:99, 2003.

The family Heteroderidae is revised. On the basis of shared, derived characters sister groups are established and arranged in a phylogenetic tree. A hypothetical, primitive ancestor for the family is defined. The genus Verutus has a large equatorial vulval slit and is considered to be the most primitive form. The genus Meloidodera developed by a reduction in vulval size. Genera which developed later exhibit a subterminally located vulval slit and progressively lost the annulation of the female cuticle. In this process four evolutionary lines emerge: (i) a posterior shift of the vulva and the formation of more or less distinct vulval lips gave rise to the genera Zelandodera and Cryphodera; (ii) changes in the lip configuration of the second-stage juvenile gave rise to the genera Hylonema, Afrodera n.g., Heterodera and Bidera; (iii) changes in the composition of the female cuticle resulted in the genera Thecavermiculatus, Atalodera, Sherodera, Sarisodera and Bellodera n.g. and; (iv) a reduction in vulval slit size led to the development of the genera Dolichodera, Globodera, Cactodera and Punctodera. The genera Ephippiodera and Rhizonema are synonymized with Bidera and Sarisodera respectively. Verutus and Meloidodera are recognized as subfamilies Verutinae and Meloidoderinae and the genera in the four evolutionary lines are recognized as subfamilies Cryphoderinae, Heteroderinae, Ataloderinae and Punctoderinae respectively. Two new genera, Afrodera and Bellodera, are erected for species originally described in Sarisodera and Cryphodera. Both new genera are characterized by a depressed vulval slit and the anus located on the dorsal side of the vulval cone. Differences in lip configuration of the infective juvenile and a postulated difference in female cuticle justifies their placement in different subfamilies. The lip configuration of the infective juveniles in the subfamilies Verutinae, Meloidoderinae, Cryphoderinae, Ataloderinae and Punctoderinae remains basically unchanged. The possible development of this character in the subfamily Heteroderinae is discussed and illustrated. The family Heteroderidae, its six subfamilies and 17 genera are defined or redefined, and for each of the genera the nominal species and their synonyms are listed. New synonyms introduced are: Heterodera rumicis and H. scleranthi of H. trifolii, H. ustinova of Bidera avenae and H. mali of Globodera chaubattia. Cactodera acnidae (Schuster & Brezina, 1979) n. comb. and Dolichodera andinus (Golden, Franco, Jatala & Astogaza, 1983) n. comb. are transferred from Heterodera and Thecavermiculatus respectively. Keys are provided for all taxa for which no suitable keys are available in the literature. Species inquirendae are listed. ac]19840606

The family Heteroderidae and the subfamilies Heteroderinae and Meloidoderinae are redefined. The subfamily Meloidogyninae is raised to family Meloidogynidae. The genus Meloidoderita Poghossian, 1966 is transferred to the family Meloidogynidae. Ataloderinae n. subfam. is proposed and diagnosed in the family Heteroderidae. A key to the three subfamilies is presented and a possible phylogeny of the family Heteroderidae is discussed.

The significance of gnotobiology, that is the study of a single species in the absence of others or in the presence of only known species, was reviewed for phytonematology by Zuckerman (1971). As early as 72 years ago Berliner and Busch (1914) tried to cultivate a cyst nematode (Heterodera schachtii Schmidt) on seedling roots in agar, but Widdowson et al. (1958) were probably the first to observe the development of such a nematode (Globodera rostochiensis (Woll. Behr.)) in sterile root culture. Now it has become a common practice to cultivate members of the Heteroderinae (which comprise the cyst-forming genera) under gnotobiotic conditions on roots in agar medium. Lauritis et al. (1983b) list the species of cyst nematodes so far successfully maintained in monoxenic culture.

Taxonomy of Heteroderinae Luc et al. (Heteroderidae sensu lato) is changing rapidly with descriptions of many new species and genera in recent years (Table 1). Contrasting approaches to classification and disagreement of synonymies are reflected in systematics of Wouts (1985), Siddiqi (1986). and Luc et al. (1988). These frequent changes and general instability of systematics contribute to identification difficulties, especially for non-specialists. One result of controversial and rapidly changing classifications is that it becomes practical and convenient to use terms that describe discrete groups but that have no taxonomie standing. For example we commonly speak and write of “heteroderids” or “ataloderines” (Table 1).