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Mediante fotografie effettuate al microscopio elettronico a scansione sono state illustrate tre specie di Acari Eriofidi infeudate all'Alloro (Laurus nobilis L.) e già conosciute: Cecidophyopsis malpighianus (Can. e Massai.) Calepitrimerus russai Di St. e Diptacus camarai Carm.; di una di tali specie, il C. russai, sono riportati anche disegni per definire meglio alcuni caratteri morfologici; è ricordato anche l'Epitrimerus carmonae K., noto per l'Alloro, ma non osservato nelle nostre ricerche. Sono inoltre descritte e illustrate con disegni e fotografie al microscopio elettronico a scansione tre nuove specie, pure viventi sull'Alloro: Cecidophyes lauri n. &p., Phytoptus lauricolus n. sp., e Calepitrimerus cerosus n. sp. ERIOPHYID MITES (Acarina: Eriophyoidea) LIVING ON LAUREL WITH DESCRIPTION OF THREE NEW SPECIES Morphological characters of Cecidophyopsis malpighianus (Can. e Massai.), Calepitri- merus russai Di St. and Diptacus camarai Carm. are illustrateci by scanning electron micrographs . The Authors describes the new species also with draws. Cecidophyes lauri n. Female. - 150 ,um long, 35 ,um thick, 37 ,um wide; fusiform in shape; color light yellowish-wite. Rostrum 23 ,um long; curved down; antapical seta present. Shield 28 ,um long, 27 ,um wide; shield design nearly obsolete. Sides of shield with some latera! lines and granules. Forelegs 26 ,um long; Tibia 5 ,um long with seta 7 ,um long at 1/3; tarsus 6 ,um long; featherclaw 5 ,um long 5-rayed . Hind-legs 26 ,um long; tibia 4 ,um long ; tarsus 6 ,um long; featherclaw 5 ,um long. Coxae divergent with short centra! contact of anterior coxae. First setiferous coxal tubercles ahead of anterior coxal approximation; second setiferous coxal tubercles wel! ahead of line across third; second tubercles sur- rounded by curved lines. Abdominal thanosome with about 35 tergites and 47 sternites; the microtubercles elongate subdorsally and dorsally; touching rear ring margin'; slightly acuminate at rear. Latera! seta 19 ,um long on ring 8; first ventral seta 50 ,um long on ring 18; second ventral seta 9 f'ffi long on ring 29. Abdominal telosome with about 6 rings; telosomal seta 16 1-'ffi long. Accessory seta absent. Female genitalia 18 f'm wide and 12 f'ffi long; coverflap with about 16 longitudinal ribs, partly broken into two uneven ranks; seta 10 f'm long. Male . - about 125 f'm long T ype locality : Bari, September 1976 Collected: by N. VovLAS Host: Laurus nobilis L. Relation to host: the mites make small erineum tufts on the underside of the leaves; this erineum is of single hairs and is situated at the angle between the midrib and a main side vein. Type material: a type slide, six paratipe slide, a slide sent to H. H. KEIFER and a paratipe slide sent to « Istituto Sperimentale per la Zoologia agraria di Firenze»., Entomologica, Vol 13 (1977)

Trabajo presentado en la APS Annual Meeting (2015), celebrada en Pasadena del 1 al 5 de agosto de 2015., Reniform nematodes of the genus Rotylenchulus comprise a few species, which kidney-shaped mature females are semi-endoparasitic on roots. These nematodes are widely distributed across tropical and subtropical regions of the world and associated with numerous agricultural and horticultural crops. Nematode surveys of plant-parasitic nematodes undertaken during the last years in several crops including sugarcane, sorghum, maize, grapevine and wild and cultivated olives in Italy, South Africa, Spain and USA revealed heavy soil infestations by several reniform nematodes, including Rotylenchulus clavicaudatus, R. leptus, R. macrosoma, R. macrodoratus, R. reniformis, R. sacchari and an unknown species parasitizing sugarcane in South Africa. These species were characterized and differentiated from each other using the D2-D3 of 28S rRNA, ITS rRNA, hsp90 and coxI mtDNA gene sequences. In this study we also provided phylogenetic relationships within Rotylenchulus as inferred from the Bayesian analysis of these genes. PCR with species-specific primers was developed for rapid and accurate diagnostics of the pathogenic species R. reniformis. Sequence and phylogenetic analysis revealed two distinct and divergent paralogs of rRNA genes for R. reniformis and an unknown Rotylenchulus species.

The genus Hemicycliophora (Nematoda: Hemicycliophoridae) contains 132 valid species of plant-parasitic nematodes, collectively known as ‘sheath nematodes’. Hemicycliophora spp. are characterized morphologically by a long stylet with rounded basal knobs and a cuticular sheath, present in juvenile and adult stages. Populations of 20 valid and 14 putative species of Hemicycliophora and Loofia from several countries were characterized morphologically using light (LM) and scanning electron microscopy (SEM) and molecularly using the D2-D3 segments of 28S rRNA and internal transcribed spacer (ITS) rRNA gene sequences. LM and SEM observations provided new details on the morphology of these species. PCR-restriction fragment length polymorphisms (PCR-RFLPs) of the D2-D3 of 28S rDNA were proposed for identification of the species. Phylogenetic relationships within populations of 36 species of the genus Hemicycliophora using 102 D2-D3 of 28S rDNA and 97 ITS rRNA gene sequences as inferred from Bayesian analysis are reconstructed and discussed. Ancestral state reconstructions of diagnostic characters (body and stylet length, number of body annuli, shape of vulval lip and tail), using maximum parsimony and Bayesian inference, revealed that none of the traits are individually reliable characters for classifying the studied sheath nematode. The Shimodaira–Hasegawa test rejected the validity of the genus Loofia. This is the most complete phylogenetic analysis of Hemicycliophora species conducted so far. Fil: Subbotin, Sergei A.. California Department of Food and Agriculture; Estados Unidos. Institute of Ecology and Evolution of the Russian Academy of Sciences; Rusia Fil: Chitambar, John J.. California Department of Food and Agriculture; Estados Unidos Fil: Chizhov, Vladimir N.. Institute of Ecology and Evolution of the Russian Academy of Sciences; Rusia Fil: Stanley, Jason D.. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Inserra, Renato N.. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Doucet, Marcelo Edmundo. Universidad Nacional de Cordoba. Facultad de Cs.exactas Fisicas y Naturales. Centro de Zoologia Aplicada; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Diversidad y Ecologia Animal; Argentina Fil: Mcclure, Michael. University Of Arizona; Estados Unidos Fil: Ye, Weimin. North Carolina Department of Agriculture & Consumer Services; Estados Unidos Fil: Yeates, George. Fil: Mollov, Dimitre S.. University Of Minnesota; Estados Unidos Fil: Cantalapiedra Navarrete, Carolina. Consejo Superior de Investigaciones Científicas. Instituto de Agricultura Sostenible; España Fil: Vovlas, Nicola. Istituto per la Protezione delle Piante; Italia Fil: Van Den Berg, Esther. ARC-Plant Protection Research Institute; Sudáfrica Fil: Castillo, Pablo. Consejo Superior de Investigaciones Científicas. Instituto de Agricultura Sostenible; España

The nematode Rotylenchus paravitis n. sp. infesting roots of commercial sunflowers in southern Spain is described. The new species is characterised by a truncate lip region with 7¿9 annuli and continuous with the body contour, lateral fields areolated at pharyngeal region only, body without longitudinal striations, stylet length of 44¿50m, vulva position at 43¿54%, tail rounded to hemispherical with 12¿18 annuli. A comparative phenetic study based on a multivariate principal component analysis was developed to determine potential species discrimination. The degree of variation for most characters among specimens of Rotylenchus paravitis n. sp. and R. vitis was comparable to that observed among specimens belonging to each of the two studied populations of R. robustus from Spain and USA. Molecular comparison of the partial 18S, D2-D3 expansion segments of 28S-rRNA, ITS1-rRNA, partial COI and hsp90 from R. paravitis n. sp. and R. vitis, and other species in the genus, clearly supports the proposal of R. paravitis n. sp. as a new species. Consequently, R. paravitis n. sp. should be considered as an example of cryptic speciation within the genus Rotylenchus. PCR-ITS-RFLP was provided for diagnostics of R. paravitis n. sp. and PCR with specific primers were also developed for diagnostics of this new species, R. vitis and R. robustus. The results of the phylogenetic analysis based on the sequences of the D2-D3 expansion regions of the 28S, ITS1-rRNA genes, and the partial COI, have proven to be a powerful tool for providing accurate species identification and assessing phylogenetic relationships within the genus Rotylenchus. Phylogenetic testing of D2-D3 expansion segments of 28S-rRNA gene sequences did not refute the monophyly of the genera Rotylenchus, Helicotylenchus, Hoplolaimus, based on tree topologies and the Shimodaira¿Hasegawa test even with the split in several clades for some of the genera., This research was supported by grant AGL2009-06955 from ‘Ministerio de Ciencia e Innovación’ of Spain, grant AGR-136 from ‘Consejería de Economía, Innvovación y Ciencia’ from Junta de Andalucía, and the European Social Fund.

Editors: Schena L., Agosteo G.E., Cacciola S.O.

An account is given on the 39 arthropod species which were found on different Ficus trees in the Maltese Islands. Seventeen species represent new records for Malta including Anothopoda fici, Asetadiptacus emiliae, Astichus bachmaieri, Ecphylus caudatus, Empoasca alsiosa, Eupristina verticillata, Ficocyba ficaria, Gynaikothrips ficorum, Josephiella microcarpae, Philotrypesis caricae, Pleistodontes sp., Rhaphitelus maculats, Rhyncaphytoptus ficifoliae, Scobicia chevrieri, Silba adipata, Singhiella citrifolii and Zanchius breviceps. Anothopoda fici and Zanchius breviceps, also represent new records for the entire European territory. Of the 39 arthropods, 33 feed on Ficus trees, whereas the rest are either parasitoids or predators of some of these plant feeders. The 33 species which use Ficus as their host-plant spend most of their development on and utilise the aforementioned trees as their main source of food, at least during their larval development., peer-reviewed

Morphologial, biochemical, molecular and karyological analyses of different populations and races of the stem and bulb nematode Ditylenchus dipsaci have suggested that it represents a species complex, of which only D. dipsaci sensu stricto and its morphologically larger variant, known as the giant race of the stem and bulb nematode, are plant parasites of economic importance. The present study singles out the giant race from this complex, herein described as a new species named Ditylenchus gigas n. sp., on the basis of morphological and molecular data obtained from several populations collected from broad beans in southern Italy, southern Spain and Lebanon. The new species epithet, which refers to the large body size of the nematode with respect to the normal races, must be considered to be conspecific with the D. dipsaci'giant race' from Fabaceae in recent literature. Morphologically, the new species is characterized by a body size 1·5-2 times longer than the 'normal race', stylet delicate (11·5-13·0μm long) with knobs distinctly sloping backwards, and long post-vulval uterine sac (81-150μm long). Results of molecular analysis of rDNA sequences including the ITS1-5.8S-ITS2 region, the D2-D3 fragment of the 28S gene, the small 18S subunit, the partial mitochondrial gene for cytochrome c oxidase I (mtCOI), and hsp90 gene sequences, support the new taxonomic species status for the former D. dipsaci giant race from Vicia faba, and clearly distinguish D. gigas n. sp. from D. dipsaci sensu stricto. © 2011 The Authors. Plant Pathology © 2011 BSPP., This study was partially supported by MIUR/FAR No. 2628 ‘Molecular Biodiversity Laboratory’.

Ponencia presentada en el XLIII ONTA Annual Meeting, celebrado en Coimbra (Portugal/ del 4 al 9 de septiembre de 2011. Organización de Nematólogos de los Trópicos Americanos (ONTA), Root-lesion nematodes of the genus Pratylenchus are migratory endoparasites that are distributed worldwide and are regarded as severe constraints of many crops. Proper identification of these nematodes (> 70 species) is critical for their management and phytosanitary purposes. The morphological separation of Pratylenchus species is complicated due to their high morphological plasticity, the small number of the differential characters available and high intraspecific variability of some of these characters. During the last decades, new approaches based on biochemical, molecular and phylogenetic analyses have provided powerful tools to nematode systematics and reliable identification of Pratylenchus spp. In particular the ITS, 18S and 28S ribosomal regions have been largely used to discriminate among different populations and species of Pratylenchus. The need for applying a polyphasic approach to characterize Pratylenchus species, and, in addition, to demonstrate the existence of cryptic or complex species, which are morphologically indistinguishable but genetically divergent, has been shown in recent morphological and molecular studies of members of this genus. The findings of these studies, conducted in the last decade, have produced a great number of new sequences and taxa used for testing hypotheses of phylogenetic relationships within Pratylenchus and have emphasized the importance of polyphasic taxonomy as a better strategy to delimit species and to infer phylogenetic relationships in this complex group of nematodes.

Trabajo presentado en la The Society of Nematologists 50th Anniversary Meeting, celebrada en Corvallis (Oregon, Estados Unidos) del 17 al 21 de julio de 2011.

Póster presentado en el 20th Nematology Symposium of the NSSA, celebrado en Sudáfrica del 16 al 18 de mayo de 2011., Trichodoridae are polyphagous root ectoparasites occurring worldwide. Their major pest status is as virus vector of Tobraviruses. Currently, the family has 102 species classified within 6 genera. 88% of the species belong to the didelphic genera (females with two well developed genital branches) with the genus Trichodorus being the largest in number of species (56). Trichodorus species predominantly occur in temperate regions. Surveys for trichodorids were carried out in cultivated and natural habitats in Spain and compared with the trichodorid fauna from Portugal. A comparative morphological study was carried out together with molecular analyses based on nuclear ribosomal RNA genes (D2-D3 expansion segments of 28S and partial 18S gene). Characteristic for the Iberian Peninsula is the high number of morphologically closely resembling species but clearly separated molecularly (cryptic species), characterized in males by slightly ventrally curved spicules with a mid-blade constriction with bristles and females with relatively large vaginal sclerotized pieces, quadrangular to triangular in shape. Molecular analyses demonstrated that D2-D3 expansion segments are suitable diagnostic markers for Trichodoridae. Comparative morphology and molecular analyses provide support for the Iberian Peninsula as an apparent centre of speciation. South Africa is another known centre of speciation of Trichodorus.

3 páginas, 2 figuras., A root-knot nematode was frequently detected on the roots of peony (Paeonia lactiflora Pall.) in northern Italy, inducing typical spherical galls with large egg masses (each averaging 320-350 eggs). According to its typical cuticular perineal pattern, esterase and malate dehydrogenase phenotypes, and morphological observations on adults and juveniles, the nematode was identified as Meloidogyne hapla. Galls induced by the nematode on the roots of peony were variable in size but relatively small (only two to three times the healthy root diameter), located mostly along the root axis and less frequently at the root tips. Numerous lateral roots arising from galled main roots were also galled. Comparative histopathological observations of healthy and M. hapla-infected roots of peony showed cellular alterations induced by the nematode in the cortex, pericycle and vascular parenchyma. Permanent feeding sites of the nematode within root tissues consisted of 3-8 giant polynucleate cells surrounding the lip region of females., Work partially supported by the project FLORPRO - CRA FSO (Sanremo, Italy).

Stunted growth of large patches of cabbage cv. Lupini, associated with severe soil infestations by the root-knot nema- tode Meloidogyne javanica and the protist Plasmodiophora brassicae , the casual agent of clubroot disease, was observed in several fields at Castellaneta, province of Taranto, in southern Italy. The host-parasite responses of cabbage roots to parasitism by t he two soil-borne pathogens was studied and compared. In roots infected by P. brassicae , the plasmodia were present in cortex and peri- cycle cells, causing hypertrophy and hyperplasia, and developed into resting spores within host tissues. Parasitism of M. javanica was characterized by the establishment of distinct permanent feeding sites with giant cells in the cortex, endodermis and vascu lar parenchyma, which limit water and nutrient translocation.

Resumen del trabajo presentado en el 9th International Congress of Plant Pathology, celebrado en Torino (Italia) del 24 al 29 de agosto de 2008., The primary goal of this study was to determine the extent of soil infestation and rootstock infection by plant-parasitic nematodes in 75 commercial vineyards distributed over the main grapevine-growing areas of Andalusia, southern Spain. Plant-parasitic nematodes potentially damaging grapevine rootstocks in the surveyed area included root-knot (Meloidogyne arenaria, M. incognita, M. javanica), ring (Mesocriconema xenoplax), and rootlesion (Pratylenchus vulnus) nematodes, as well as the virus-vector, dagger nematodes (Xiphinema index, and Xiphinema italiae). High level of field infestations by X. index, and X. italiae (more than 50 nematodes/100 cm3 soil) were found in vineyards affected with severe decline and reduced vigour in two locations. Soil infestations by X. index and X. italiae have the potential to impair root function. Moreover, infection of grapevines by Grapevine fanleaf virus (GFLV) transmitted by those nematodes can further result in a reduction in the lifespan of vineyards by about 12-20 years. Therefore, research is in progress for the detection of GFLV in the nematode-infected plants and in nematodes from soil that might be related to the severe plant decline. Histopathological observations of Meloidogyne-infected rootstocks revealed important alterations in roots which would negatively affect capacity for nutrient and water uptake and transport. Furthermore, our histological observations and data on nematode reproduction in infected roots indicate that some of the most commonly used rootstocks in Andalusia, including Paulsen 1103, Richter 110, Rupestris du Lot, and SO4, which previously were considered moderately resistant to Meloidogyne spp., should now be considered susceptible to the populations of these nematodes prevailing in vineyard soils in Andalusia.

Plant-parasitic nematodes are an important group of soil borne pathogens causing yield loss to crop plants. The spiral plant-parasitic nematode genus Rotylenchus is a cosmopolitan group of nematodes which is predominantly found in temperate regions of the world. In this genus are included a number of species of significant economic importance in agriculture. They parasitise a wide-range of hosts, including vegetables, ornamentals, and fruit and forest trees. We therefore considered it useful to collect in a book all the information available in the current literature. Our views, which are the result of hard and patient work, are offered in this volume. The book comprises seven sections and presents summarised and specialised information on various aspects of the spiral nematodes belonging to the genus Rotylenchus. Sections 1 and 2 describe the importance of Rotylenchus species in agricultural crops, their distribution and numerous aspects of their biology, feeding habits, pathogenicity to vegetables, fruit and forest trees, and ecology. Section 3 presents different management strategies for the most important and pathogenic species of Rotylenchus, including chemical control, crop rotation, and biological control by means of nematophagous fungi, entomopathogenic nematodes, the hyperparasitic bacteria Pasteuria penetrans, and nematicidal plants. Sections 4 and 5 describes the most important morphological characters used in characterising and diagnosing species, as well as a broad discussion on the taxonomy and systematics in Rotylenchus and related genera, including a list of nominal species. These sections also include morphometric and cluster analyses in order to separate groups of species in order to facilitate identification. Section 6 provides a complete description and measurements of all populations characterised for each species, as well as their world distribution. Finally, Section 7 includes comprehensive tabular and dichotomous keys for species identification. Whilst recognising the complexity of creating a system to identificate such a large number of species, we are nevertheless confident that, by using both systems, the reader has the wherewithall to identify the species of Rotylenchus they are dealing with.