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The occurrence of Xiphinema species in the rhizosphere of vineyards showing general decline phenotype in North Italy was investigated. Most of the collected soil samples contained two Xiphinema species belonging to X. americanum-group, along with X. index. Using the integrative taxonomy approach, combining morphological, molecular and multivariate morphological analyses, the two populations of the X. americanum-group were identified as X. rivesi and X. pachtaicum. Furthermore, one male specimen of X. rivesi was recovered and the presence of three juvenile developmental stages was confirmed based on the scatter diagram. D2-D3 expansion domains of LSU, ITS region and partial COI were used to determine the phylogenetic relationships of the two Xiphinema species from North Italy with other species belonging to X. americanum-group. Five other Xiphinema populations from different geographical areas were included in this study and only molecularly identified as X. rivesi, X. pachtaicum and X. incertum by sequencing the ITS and D2-D3 expansion domains of LSU rDNA. [ABSTRACT FROM AUTHOR]

The eriophyoid mite Aceria massalongoi (Canestrini) was collected from globoid leaf galls on severely injured chaste trees, Vitex agnus-castus L. (Lamiaceae), in Bari and Bernalda (southern Italy), and on the Ionian island Leukade (Greece). Female, male and nymph were described in detail, following the current morphometric descriptive scheme, supplementing older and incomplete descriptions. Molecular characterization of A. massalongoi from Italy and Greece was conducted by amplifying and sequencing the ribosomal ITS, the D2–D3 expansion domains of the 28S rRNA gene and the mitochondrial COI, for the first time. Phylogenetic trees based on the three molecular markers showed congruent results, confirming that Italian and Greek A. massalongoi populations are the same species that cluster together with some intraspecific variability. Galls, ranging from 0.5 to 2.8 mm in diameter, were randomly distributed on both leaf surfaces, and protruded ca. 1 mm from the leaf surface. Sometimes they were closely aggregated on midrib and leaves, which, consequently, appeared strongly deformed. Close-up observations revealed that gall induction causes hyperplastic proliferation of leaf tissues around the gall chamber hosting mites. The uniserial cell lining inside this chamber provides the nutritional tissue for the mites. All feeding cells contained one or more (frequently 2–3) hypertrophied nuclei and dense granular cytoplasm. [ABSTRACT FROM AUTHOR]

During nematode surveys in France and in South Italy, several Pratylenchus populations were collected which were morphologically related to P. penetrans. The root-lesion nematode P. penetrans is widely distributed across the world and is considered one of the most economically damaging species in the genus. Correct identification of this species is needed. Unfortunately, most of the species belonging to the penetrans group are very difficult to identify morphologically. Thus DNA-based identification can be used as a rapid diagnostic tool. Therefore the ITS, the D2-D3 expansion domains of the 28S rRNA gene and the hsp90 gene of P. penetrans and of other Pratylenchus species were amplified. Sequence analyses of all molecular markers confirmed the high variability of P. penetrans genome. The phylogenetic reconstruction based on the sequences of the ITS and D2-D3 expansion domains confirmed the high sequence variability among the different populations of P. penetrans and the close relationships with the penetrans group. Furthermore, the isolation of two variants of the hsp90 gene in P. penetrans may be related to adaptation to environmental changes and different host plants. [ABSTRACT FROM AUTHOR]

Cyst nematodes obtained from commercial carrot fields in Ontario (Canada) and northern and southern Italy were subjected to morphological and molecular examination. Morphology of cyst cone tops, males and second-stage juveniles (J2) indicated the nematode species was the Carrot Cyst Nematode (CaCN), Heterodera carotae. The sequence of the Internal Transcribed Spacer (ITS), D2-D3 region of the 28S gene of ribosomal RNA, cytochrome oxidase I of mitochondrial DNA (coxI), and a heat shock protein gene (hsp90), from single cysts were also examined. Sequences of ITS and D2-D3 placed all the nematodes with Heterodera carotae and other Heterodera spp. belonging to the Goettingiana group in the same clade. The novel nine coxI sequences obtained also clustered in a well-supported phylogenetic clade for H. carotae. Similarly, the six new hsp90 sequences of H. carotae generated in this study were placed in a well-supported clade (PP = 1.00) together with other two sequences of H. carotae from Greece. Restriction Fragment Length Polymorphism (RFLP) of ITS-PCR products gave a restriction pattern for RsaI different than H. carotae but the other 6 restriction patterns were similar as described in former research. A diagnostic conventional PCR method was developed based on a primer set to be specific for H. carotae using coxI sequence. These primers were also used in real time PCR to generate a melt curve specific to H. carotae. Limit of detection for CaCN in conventional PCR reaction was a single J2. [ABSTRACT FROM AUTHOR]

The spiral nematode Helicotylenchus oleae is an ectoparasite of olive roots and is distributed in some countries in the Mediterranean Basin. In this study, we provided morphological and molecular characterisation of topotypes from southern Italy, as well as of several other populations from Crete (Greece) and Spain. Correct identification of plant-parasitic nematode species is essential to establish appropriate control strategies and for preventing their spread to other areas. Helicotylenchus oleae is reported for the first time in Greece (Crete). Integrative morphometric and molecular data for H. oleae populations using D2-D3 expansion segments of 28S rDNA, ITS-rDNA, and the cytochrome c oxidase subunit 1 (coxI), were in agreement with the original descriptions of the species, except for some minor differences, which may be a result of intraspecific variability. The phylogenetic relationships of this species with other representatives of Helicotylenchus spp. using D2-D3 expansion segments and the ITS-rRNA region was studied showing a low intraspecific diversity for H. oleae species. For the first time, coxI molecular data is obtained for the genus Helicotylenchus [ABSTRACT FROM AUTHOR]

This research carried out an accurate identification of the root-knot and cyst-forming nematode species parasitizing white clover at the Laceno Lake area in Southern Italy. Two species, the root-knot nematode Meloidogyne hapla and the cyst nematode Heterodera daverti were identified by integrative taxonomic approaches (classical, isozyme pattern, and D2-D3 expansion segments of 28S rRNA, ITS rRNA and coxI of mtDNA gene sequences) and found parasitizing white clover roots. These nematodes were detected in stunted plants with a reduced number of rhizobium nodules and the host suitability was confirmed by the high nematode population densities ranging from 53 to 2350 eggs and J2s per g of fresh roots for M. hapla, and 1.36 eggs and J2s/cm of soil for H. daverti; and cyst nematode females were also detected on the roots of clover. The studies on the host-parasite relationships of nematode-feeding sites in white clover roots infected by these nematodes showed a high susceptible response. Meloidogyne hapla and H. daverti infections were also observed on nitrogen-fixing root nodules of white clover, where well established feeding sites allowed active nematode reproduction. Histological examination of nitrogen-fixing root nodule tissues revealed that the nematodes established their permanent feeding sites in the vascular bundles of nodules which appeared enlarged deformed and disorganised by the expansion of nematode feeding cells (giant cells and syncytium) and hyperplasia of the nodule cortex. Additionally, coxI of mtDNA gene is an efficient barcoding sequence for discriminating the identification of H. daverti from H. trifolii. [ABSTRACT FROM AUTHOR]

During a survey, in the Perthshire hills, Scotland, altitude 800-900 m a.s.l., samples of Dryas octopetala leaves showing concomitantly symptoms of galls and discolored spots, were collected. Several nematodes, juveniles and adults, were isolated by dissecting foliar tissues. Two species of nematodes, recovered and identified at morphological and molecular level as Aphelenchoides sp. and Subanguina radicicola, are herein reported. The most significant diagnostic characters for species identification of nematode specimens extracted from Dryas leaf galls fitted well with those previously reported for S. radicicola. Concerning the Aphelenchoides sp., the diagnostic characters were very similar to those reported for A. ritzemabosi.The ITS and the D2-D3 expansion domain analyses confirmed the presence of S. radicicola from galls, while Aphelenchoides specimens from discoloured leaf areas), despite the morphological similarity with A. ritzemabosi, were genetically distinct from A. ritzemabosi based on two genomic regions (LSU and ITS). The 18S rRNA gene (SSU) was only amplified in S. radicicola. Phylogenetic analyses using ITS and LSU sequences placed S. radicicola with other populations of the same species and Aphelenchoides sp. with species of the same genus. The histopathology, caused by both endoparasites in naturally infected leaves, was examined via serial sections mounted on glass slides. Green Dryas leaves infected by Aphelenchoides sp. appeared discolored (yellowish spots), slightly deformed with a population density of four specimens/cm per single leaf blade. Dryas octopetala leaves infected by S. radicicola showed an average of three galls/leaf, located randomly, mainly at the upper leaf edge. Dissected galls contained a central cavity with a variable number of adult females (3-6)/gall and males, together with several immature females, juvenile stages and eggs. The present study reports on a new host plant and an undescribed type of sedentary parasitism of the root-gall nematode, S. radicicola on D. octopetala leaves with the concomitant infection of specimens of Aphelenchoides sp. [ABSTRACT FROM AUTHOR]

The reniform nematodes of the genus Rotylenchulus are semi-endoparasites of numerous herbaceous and woody plant roots and distributed in regions with Mediterranean, subtropical and tropical climates. In this study, we provide morphological and molecular characterisation of three out of 11 valid species of the genus Rotylenchulus: R. macrodoratus, R. macrosoma, and R. reniformis from Greece (Crete), Italy and Spain. The overall prevalence of reniform nematodes in wild and cultivated olives in Greece, Italy, and Spain was 11.5%, 19.0% and 0.6%, respectively. In Greece, R. macrodoratus and R. macrosoma were detected in cultivated olive with a prevalence of 8.2% and 6.2%, respectively, but none of them were found in wild olive. This is the first report of R. macrosoma in Greece. Only one reniform nematode species was detected in olive from Italy and Spain, viz. R. macrodoratus and R. macrosoma, respectively. The parasitism of R. macrosoma on hazelnut in northern Spain was also confirmed for the first time. This study demonstrates that R. macrodoratus and R. macrosoma have two distinct rRNA gene types in their genomes, specifically the two types of D2-D3 for R. macrosoma and R. macrodoratus, the two types of ITS for R. macrodoratus and the testing of the ITS variability in other R. macrosoma populations in different countries. Rotylenchulus macrosoma from Greece and Spain showed differences in nucleotide sequences in the ITS region and D2-D3 of 28S rRNA gene. [ABSTRACT FROM AUTHOR]

A survey was conducted in 16 fields cultivated with broad bean ( Vicia faba L.) and garden pea ( Pisum sativum L.) in nine localities of Apulia, southern Italy, to determine whether annual weeds were susceptible to the pea cyst nematode (PEACN), Heterodera goettingiana, and could therefore serve as alternate host for the nematode. The results of this study showed that black medick ( Medicago lupulina L.) is a good host for the nematode increasing its population levels in the soil in the absence of the primary hosts. The identity of the PEACN was confirmed by integrative taxonomic approaches (classical, and molecular), resulting identical in all cases (broad bean and garden pea, as well as the spontaneous black medick infections). The phylogenetic analyses using ITS and coxI gene regions strongly support the identification of the populations of H. goettingiana from Italy. Also, ITS and coxI gene sequences were obtained from the same cyst, confirming the species identity in comparison to other nematodes and populations in the Goettingiana group, demonstrating that ITS and coxI gene regions of the PEACN are suitable molecular markers for accurate and unequivocal identification of the PEACN. Reproduction and histopathological analyses demonstrated a good host-suitability of black medick to the PEACN. This record enlarges the relatively narrow host-range of the pea cyst nematode and indicates the need to control M. lupulina to avoid the increase of the nematode population in the absence of the main host crop. [ABSTRACT FROM AUTHOR]

A new longidorid nematode, Longidorus asiaticus n. sp., is described and illustrated from a population extracted from soil associated with the movement of crape myrtle ( Lagerstroemia indica) flowering bonsai trees imported from China into Italy. The new needle nematode is characterised by a small body size (2.74-3.52 mm), a bluntly-rounded lip region, ca 12 μm wide, continuous with body contour, amphidial fovea pocket-shape with posterior end rounded not bilobed, a moderately long and flexible odontostyle ca 85 μm long, stylet guiding ring located at ca 37 μm from anterior end, vulva almost equatorial (48-54 %), tail short, about 2/3 of its width, dorsally convex-conoid, with rounded terminus, with a c' ratio ca 0.7, bearing two pairs of caudal pores and male absent. Integrative diagnosis was completed with molecular data obtained using D2-D3 expansion segments of 28S rDNA, ITS-rDNA, and partial 18S-rDNA. The phylogenetic relationships of this species with other Longidorus spp. using D2-D3 expansion segments, ITS and partial 18S-rDNA indicated that L. asiaticus n. sp. clustered together with L. hangzhouensis, Longidorus sp. JH-2014, and L. camelliae: all of them sharing a common Asiatic geographic origin. [ABSTRACT FROM AUTHOR]

The adults' mobility and oviposition preferences of Zerynthia cassandra have been studied for the first time, with the aim of integrating auto-ecological information into recommendations for the habitat's management of this species. Results of our mark-release-recapture study have highlighted that Z. cassandra is a strictly sedentary species, since detected movements only occurred over very short distances (≤200 m) and mainly within the species' reproductive habitat (i.e. around Aristolochia rotunda stands), with males moving further than females. Our study shows that the main oviposition habitat of Z. cassandra is found where A. rotunda plants are growing in large stands; sites where plants growing in half to full sun and mostly oriented to the south are preferred. The distance of deposited eggs from the plants' roots was narrowly correlated with the plants' length. Eggs were deposited singly, mainly on the underside of leaflets. Management strategies necessary for improving the most important habitat features for the conservation of this species are suggested. [ABSTRACT FROM AUTHOR]

The camellia root-knot nematode Meloidogyne camelliae was detected in Italy parasitizing roots of Japanese camellia ( Camellia sasanqua) flowering bonsai trees imported from Japan, and it represents a new record for Europe. Morphology and morphometrical traits analysis of the intercepted population of M. camelliae were in agreement with those of the original description of the species, except for some minor differences in second-stage juvenile stylet length and c ratio, spicules and gubernaculum in males, which may be a result of intraspecific variability. Integrative molecular data for this species were obtained using D2-D3 expansion segments of 28S rDNA, ITS1-rDNA, and the protein-coding mitochondrial gene COI. The phylogenetic relationships of this species with other representatives of Meloidogyne spp. using D2-D3 expansion segments and ITS1 indicated that M. camelliae clustered together with M. artiellia and M. baetica. Histological observations of C. sasanqua feeder roots infected by M. camelliae reveal slight swellings of the root feeding sites, and most egg-laying females protruding from the root. The anatomical alterations at feeding sites consist of 3-8 hypertrophied, polinucleate giant cells/female, but no hyperplasia was induced unlike what commonly occurs for most members of the genus. [ABSTRACT FROM AUTHOR]

The Japanese cyst nematode Heterodera elachista was detected parasitizing corn cv Rixxer in Bosco Mesola (Ferrara Province) in Northern Italy. The only previous report of this nematode was in Asia (Japan, China and Iran) attacking upland rice; being this work the first report of this cyst nematode in Europe, and confirmed corn as a new host plant for this species. Integrative morphological and molecular data for this species were obtained using D2-D3 expansion regions of 28S rDNA, ITS1-rDNA, the partial 18S rDNA, the protein-coding mitochondrial gene, cytochrome oxidase c subunit I ( COI), and the heat-shock protein 90 ( hsp90). Heterodera elachista identified in Northern Italy was morphologically and molecularly clearly separated from other cyst nematodes attacking corn (viz. H. avenae, H. filipjevi, H. delvii, H. oryzae, H. sacchari, H. sorghi, H. zeae, Punctodera chalcoensis, and Vittadera zeaphila) and rice ( H. oryzae, H. sacchari). The phylogenetic relationships of H. elachista from Northern Italy with other cyst-nematodes using rDNA and mtDNA showed a separation of the genus Heterodera in various morphospecies groups based on vulval cone structures. The development and parasitic habit of H. elachista on naturally infected corn cv Rixxer confirmed a typical susceptible reaction, including multinucleate syncytial cells in parenchymatic cells. Under greenhouse conditions, H. elachista successfully reproduced on two crops widely used in Northern Italy, such as corn (cv PR 33) and rice (cv Baldo). Considering the limited host-range of this nematode, that include two of the three world's most important crops, special attention is needed for avoiding the dispersal of this nematode into new areas, by movement of soil on equipment, water, and contaminated containers infested soil, or agricultural practices. [ABSTRACT FROM AUTHOR]

A population of Xiphinema macroacanthum Lamberti, Roca & Agostinelli, 1989 originating from olive orchards in Brindisi, Italy and containing both adults and all juvenile stages, is described and illustrated. The first juvenile stage is reported for the first time. Molecular characterisation of this species, using the D2-D3 expansion domains of the 28S rDNA and ITS region, was carried out. PCR-RFLP analyses of the ribosomal gene regions determined species-specific patterns that clearly differentiate X. macroacanthum. Sequences of the D2-D3 domains and the partial 18S-ITS1 rRNA genes were analysed using several methods for inferring phylogeny to reconstruct the relationships between X. macroacanthum and other Xiphinema species. [ABSTRACT FROM AUTHOR]

The non-cyst forming heteroderid nematode Cryphodera brinkmani was detected in Italy parasitizing roots of Japanese white pine bonsai ( Pinus parviflora) trees imported from Japan. Morphology and morphometrical traits of the intercepted population on this new host for C. brinkmani were in agreement with the original description, except for some minor differences on male morphology. Integrative molecular data for this species were obtained using D2-D3 expansion regions of 28S rDNA, ITS1-rDNA, the partial 18S rDNA, and the protein-coding mitochondrial gene, cytochrome oxidase c subunit I ( COI). The phylogenetic relationships of this species with other representatives of non-cyst and cyst-forming Heteroderidae using ITS1 are presented and indicated that C. brinkmani clustered together with other Cryphodera spp. and with Meloidodera alni suggesting a monophyletic origin of non-cyst forming nematodes (Heteroderinae sensu Luc et al. ), which have been considered close to the ancestor of most species of Heteroderidae. Histological observations of P. parviflora feeder roots infected by C. brinkmani indicated that nematode females induce similar anatomical alterations to those reported for C. kalesari, consisting of formation of a single uninucleate giant cell (nurse cell) with hypertrophied nucleus, prominenet nucleolus, thickened cell wall and expanding into the stele and in contact of xylem, vacuum cambium and phloem. These findings are in agreement with the results of the phylogenetic analysis and indicate a close relationship in the plant responses induced by Cryphodera nematode females with those caused by the genetically related Meloidodera spp., which also induce formation of a uninucletate giant cell. [ABSTRACT FROM AUTHOR]

During nematode surveys in southern Spain and Italy 14 populations of Xiphinema species tentatively identified as Xiphinema americanum-group were detected. Morphological and morphometrical studies identified three new species and six known Xiphinema americanum-group species, viz.: Xiphinema parabrevicolle n. sp., Xiphinema parapachydermum n. sp., Xiphinema paratenuicutis n. sp., Xiphinema duriense, Xiphinema incertum, Xiphinema opisthohysterum, Xiphinema pachtaicum, Xiphinema rivesi, and Xiphinema santos. The Xiphinema americanum-group is the most difficult Xiphinema species group for diagnosis since the morphology is very conservative and morphometric characters often overlap. This group includes vectors of several important plant pathogenic viruses that cause significant damage to a wide range of agricultural crops. Molecular characterisation of these species using D2-D3 expansion regions of 28S rRNA, 18S rRNA, ITS1-rRNA and the protein-coding mitochondrial gene, cytochrome oxidase c subunit 1 was carried out and maximum likelihood and Bayesian inference analysis were used to reconstruct phylogenetic relationships among these species and with other Xiphinema americanum-group species. [ABSTRACT FROM AUTHOR]

The biological and molecular characterization is reported of a Watermelon mosaic virus isolate, denoted WMV-Le, associated with a necrotic phenotype of watermelon plants grown in the Provinces of Lecce and Taranto (Apulia, southern Italy). The fully sequenced WMV-Le genome consists of 10,045 nucleotides and is 99.1% similar to that of WMV-C05-270, a French isolate from melon of the WMV molecular group 3. Using recombination detection program RDP3, putative recombination breakpoints were identified close to nucleotide positions 42 to 1892, covering the 5′UTR/P1/HC-Pro region. The event represents the insertion of a sequence fragment of an isolate similar to WMV-FBR04-37 in the background of an isolate similar to WMV-FMF00-LL1. The field symptomatology was reproduced in watermelon plants grown in an experimental greenhouse but the virus induced severe symptoms also in Cucumis sativus, C. melo, Cucurbita maxima and C. pepo . [ABSTRACT FROM AUTHOR]

During a nematode survey, severe infections of tobacco feeder roots and heavy soil infestations by Meloidogyne incognita race 1 were found in S. Miguel (Azores islands, Portugal). This is the first record of M. incognita infection of tobacco in Azores. Morphology of various life stages, analysis of the esterase electrophoretic pattern and differential host tests were used for nematode characterization and identification. Nematode-induced mature galls were spherical and/or ellipsoidal and usually contained more than one female, males and egg masses with eggs. Feeding sites were characterized by the development of giant cells that contained granular cytoplasm and many hypertrophied nuclei. Giant cell cytoplasm was aggregated along a thickened cell wall. Vascular tissues within galls appeared disorganized. The relationship between the initial nematode population density and growth of tobacco plants was tested in a glasshouse experiment in which inoculum levels varied from 0 to 512 eggs and juveniles (J2) cm−3 of soil. Seinhorst’s model was fitted to height and top fresh weight data of the inoculated and control plants. Tolerance limits with respect to plant height and fresh top weight of tobacco cv. ‘Erzegovina’ plants to M. incognita race 1 were estimated as 1.25 eggs and J2 cm−3 of soil. The maximum nematode reproduction rate was 404.7 at an initial population density of 4 eggs and J2 cm−3 of soil. [ABSTRACT FROM AUTHOR]

A cucumber mosaic virus (CMV) isolate supporting a natural 390-ribonucleotide satellite was used to reproduce under experimental conditions a disease of processing tomatoes called fruit necrosis. The virus induced incomplete differentiation of the vascular tissue of fruit stalks, which was the likely cause of the disease. On the other hand, the satellite RNA attenuated viral symptoms on tomato leaves reproducing the disease pattern typically observed in the field. The biological properties of this seemingly new variant of cucumoviral satellite RNAs were determined. [ABSTRACT FROM AUTHOR]

Results Paragraph: Ribosomal sequence characterization. Fig. 1: This figure is missing and the legend of Fig. 1 is erroneously labeled as Fig. 2, and associated to the phylogenetic tree which corresponds to Fig. 2. [ABSTRACT FROM AUTHOR]