bluuebunny/crossref_metadata_2025 huggingface dataset:
Present status of verticillium wilt of olive in Andalucía (southern Spain)1
Authors: JURADO D. RODRIGUEZ , LÓPEZ M. A. BLANCO , RAPOPORT H. F. , DIAZ R. M. JIMENEZ
Published: April 2008

Verticillium wilt caused by Verticillium dahliae is a disease highly prevalent in newly established olive orchards in Andalucía, southern Spain. Two syndromes of the disease occur in Andalucia, namely apoplexy and slow decline. Apoplexy is characterized by quick dieback of twigs and branches while slow decline consists of rapid drying out of inflorescences together with leaf chlorosis and necrosis. Systematic disease observations carried out in two experimental orchards planted with susceptible cv. Picual indicated that natural recovery of diseased trees occurred over time. Infection and vascular colonization of olive plants by V. dahliae were studied in susceptible (Picual) and resistant (Oblonga) cultivars inoculated with a mildly virulent or a highly virulent cotton‐defoliating isolate of V. dahliae. Disease symptoms developed 24–32 days after inoculation in cv. Picual, but at that time plants of cv. Oblonga remained free from symptoms. However anatomical observations and isolations indicated that systemic infections by the two isolates had occurred to a large extent in both cultivars.
Verticillium wilt of olive in Syria1
Authors: AL‐AHMAD M. A. , MOSLI M. N.
Published: April 2008

Verticillium wilt of olive was first recorded in Syria in mid‐1978 and confirmed as due to Verticillium dahliae. This article reports observations made in a comprehensive survey of the disease in nine provinces over 7 years. Percent infection varied from 0.85 to 4.5 in different provinces. Newly planted groves in lowland areas showed more infection than older groves in hilly areas. Isolation of V. dahliae was possible at all times of year. Young trees were more susceptible to wilt than older ones. The performance of 13 local cultivars against wilt was studied under natural field conditions and found to vary greatly from susceptible to resistant. Agricultural practices greatly affect spread of the disease. High disease incidence was observed in irrigated groves compared with non‐irrigated, and correlated positively with number of ploughings. Verticillium wilt causes a loss between 1 and 2.3% of total olive production annually.
Systems of designation of pathotypes of plant pathogens12
Authors: LIMPERT E. , CLIFFORD B. C. , DREISEITL A. , JOHNSON R. , MÜLLER K. , ROELFS A. , WELLINGS C.
Published: April 2008

A variety of systems of designation has evolved to name pathotypes of plant pathogens. The systems were evaluated to determine those best suited for particular purposes. Virulence and avirulence/virulence formulae of pathotypes have advantage over the use of consecutive numbers or letters given in chronological order of pathotype discovery. As soon as pathotype information exceeds a certain level of complexity, mathematical codes are most advantageous, in particular two codes, octal notation and coded triplets. A more universal adoption of the most appropriate codes is recommended to ease communication and comparisons of results.
Viability test for Peronospora tabacina in stored Greek oriental tobacco
Authors: ZHANG Z. , LI Y. Z. , QI L. J. , ZHANG L.
Published: April 2008

During recent years, Peronospora tabacina has frequently been intercepted on leaves in lots of imported Greek oriental tobacco at ports of entry in China. The question arises whether such infected leaf debris can be a source of primary inoculum. The present study has examined the pre‐export viability of P. tabacina on stored Greek oriental tobacco. Firstly, basic experiments were done: (1) to find a suitable medium (2% Bacto (Difco) agar) for in vitro germination of P. tabacina sporangia; (2) to determine the optimum (15–21 °C), maximum (30°C) and minimum (2°C) temperatures for sporangial germination; (3) to devise a suitable method of inoculation for an infectivity test. Secondly, viability tests were done on stored Greek oriental tobacco harvested in 1986 and 1987. In vitro germination tests and infectivity tests were conducted separately, according to microscopic grading of the apparent turgidity of sporangia and sporangiophores collected from lesions of infected tobacco leaves of different cultivars and crop years. The tests were maintained for a much prolonged incubation period as compared with the controls. Neither in vitro germination nor infectivity tests showed any sporangia to be viable. Further work is needed to determine what period of storage is rationally acceptable for both plant quarantine and commercial trade.
First occurrence of fireblight in Romania
Authors: BAICU T. , SEVERIN V. , BRANISTE N. , RACHITEANU A. , AMZAT V. , VAN DER ZWET T.
Published: April 2008

Fireblight was first observed in Romania in 1992‐08 near Braila, and shortly after in the pear collection of the Fruit Research Institute in Pitesti‐Maracineni. Advanced symptoms indicated that the disease was present at least one year earlier. Symptomatology, fruit pathogenicity, selective culture media, hypersensitivity, agglutination and fatty acid class analysis confirmed the authenticity of the pathogen as Erwinia amylovora. Of the native Romanian fruit cultivars affected, apple cv. Delicios de Voinesti and pear cv. Aromat de Bistrita appear the most susceptible to fireblight.
Assessment of brown rot severity on the basal part of wheat stems
Authors: ROSSI V. , BATTILANI P. , CHIUSA G. , RACCA P.
Published: April 2008

A new scale (the BFR scale) for the assessment of Brown Foot Rot severity on wheat stems is described. Six classes of percentage of affected stem circumference are considered (0, 5, 25, 50, 75 and 100%) applied using a standard diagram. Replicability, reproducibility, accuracy and resolution of disease symptoms assessment made by five observers are discussed. The BFR scale allows accurate estimates of disease severity of brown foot rot on wheat when assessments are carried out by skilled observers. This is of particular importance given that both the object (the stem) and the extent and range of disease symptoms are difficult to assess.
The various means of dissemination of the fire blight bacterium Erwinia amylovora
Authors: VAN DER ZWET T.
Published: April 2008

A brief review is presented of the means of dissemination of Erwinia amylovora. The bacterium exists in the form of ooze, strands, epiphytic populations and endophytic populations. The status of endophytic bacteria in budwood and fruits is discussed. International dissemination of fire blight has taken place by wind, probably by birds, and by movement of budwood. It has been suggested that fruits may be involved, but there is international disagreement whether measures should be taken to protect against this pathway of dissemination.
Viruses of grapevine in Albania
Authors: MERKURI J. , MARTELLI G. P. , BOSCIA D. , SAVINO V.
Published: April 2008

Grapevines were surveyed for the presence of virus and virus‐like diseases in the Albanian viticultural districts of Shkoder, Lesh, Kruje, Durres, Tirana, Elbasan, Lushnje and Vlora. Symptoms of grapevine degeneration, leafroll and rugose wood were observed in all areas surveyed, whereas fleck was found in volunteer plants of Vitis rupestris at Elbasan, and enation disease in a few vines near Durres. Viruses identified were grapevine fanleaf nepovirus, grapevine fleck virus, grapevine virus A, and grapevine leafroll‐associated closteroviruses I and III. ELISA tests showed that 83.5% of 530 Vitis vinifera vines and 46% of 24 American rootstocks individually checked were infected by one or more viruses. The presence of Xiphinema index, the major vector of grapevine fanleaf nepovirus, was recorded from vineyards affected by yellow mosaic.
Plum pox: advances in research on the disease and its causal agent, and possible means of control1
Authors: DUNEZ J. , RAVELONANDRO M. , CANDRESSE T.
Published: April 2008

Tremendous progress has been made in research on plum pox potyvirus (PPV) in recent years, allowing significant improvements in disease control to be expected in the near future. First, new detection techniques, especially the Polymerase Chain Reaction (PCR) coupled with an immunocapture step, provide sensitivity 2000 times better than that obtained with ELISA; in addition, several techniques (PCR, western blotting, monoclonal antibodies) now allow precise strain identification. Secondly, the organization of the viral genome has been described, genome expression studied and infectious transcripts obtained which allow investigation of the molecular basis of the properties of PPV. Thirdly, significant progress has also been made in obtaining apricot hybrids with a high level of resistance. Breeding for resistance in peach is carried out by interspecific hybridization. In addition, the first transgenic Prunus plants expressing the PPV coat‐protein gene have been obtained; they are now under investigation for resistance to PPV and the coat protein strategy has already proved to be effective against PPV in Nicotiana plants. Over the next 5 years, we can expect the introduction in the field of the first resistant cultivars and therefore a progressive reduction in disease impact.
Detection of plum pox potyvirus and analysis of its molecular variability using immunocapture‐PCR1
Authors: CANDRESSE T. , MACQUAIRE G. , LANNEAU M. , BOUSALEM M. , WETZE T. , QUIOT‐DOUINE L. , QUIOT J. B. , DUNEZ J.
Published: April 2008

We have developed an immunocapture‐PCR (IC‐PCR) detection technique for plum pox potyvirus (PPV) which is both simple and highly sensitive. This single‐day assay can detect about 2000 virus particles (200 fg of virus) diluted in 100 μl of crude plant sap, which is equivalent to a sensitivity about 2000 times better than that of a standard ELISA assay. RFLP analysis and sequencing of the amplified cDNA fragment indicate that three groups of strains with limited intra‐group variability can be discriminated. Two of these groups correspond to the previously described D and M serotypes of PPV. The third group contains, so far, only the El Amar Egyptian isolate. Strains belonging to the D or M serotypes can easily be discriminated by Rsal polymorphism in the amplified cDNA fragment. Synthetic oligonucleotides allowing specific amplification of PPV strains belonging either to the D or to the M serotypes have also be designed.
A simple and rapid method for processing tissue infected with plum pox potyvirus for use with specific 3’non‐coding region RT‐PCR assays1
Authors: LEVY L. , HADIDI A.
Published: April 2008

A rapid, simple method for preparing plant tissue infected with plum pox potyvirus (PPV) using a commercial product known as Gene Releaser is described. The Gene Releaser polymeric matrix method produces plant extracts suitable for PCR amplification without the use of organic solvents, ethanol precipitation, or additional nucleic acid purification techniques. We also describe the development of a PPV‐specific amplification assay based on the unique 220 nucleotides present in the 3’non‐coding region of the PPV genome. This paper demonstrates the simplicity of the Gene Releaser method combined with the accuracy of the PCR assay for the detection of multiple PPV strains from Spain, France, Greece, Italy, Germany, Egypt, Hungary, and Romania. Amplification of the 3’non‐coding region of potato Y potyvirus (PVY) using primers for the 3’non‐coding region of the PVY genome was also possible with Gene Releaser preparation of viruliferous Myzus persicae to demonstrate the potential usefulness of this work for PPV detection from aphids.
Cross reactions of an antiserum to plum pox potyvirus1
Authors: JAMES D. , THOMPSON D. A. , GODKIN S. E.
Published: April 2008

In the early spring of 1992, plum pox‐like viruses (PPLVs) were detected by standard ELISA in some Prunus species. The isolates reacted positively with plum pox potyvirus (PPV) antisera in immunosorbent electron microscopy and Western blot analysis. In Western blot analyses, bands associated with the coat protein subunits of the PPLVs were 48–56 kDa, whereas bands associated with the coat protein subunits of known PPV isolates were 32–37 kDa in size. Also, the PPLVs differed from known PPV isolates in their symptoms on woody and herbaceous indicators, and in their herbaceous host range. None of these PPLVs appears to be an isolate of PPV.
Plum pox potyvirus on sour cherry in Moldova
Authors: KALASHYAN YU. A. , BILKEY N. D. , VERDEREVSKAYA T. D. , RUBINA E. V.
Published: April 2008

Plum pox potyvirus (PPV) was identified in six cultivars of sour cherry in the collection orchard of the Moldavian Horticultural Research Institute. Study of biological properties of the sour cherry isolate in herbaceous indicators showed its similarity or identity with the PPV isolate of Van Oosten and a significant difference from isolates widespread in Moldova. A purified viral preparation was used to develop antiserum with a working titre of 1:1024. Comparative serological examination of the sour cherry and conventional plum PPV isolates using ELISA, ISEM and SDS‐PAGE of the protein capsid could not differentiate these isolates. The sour cherry isolate was transferred to plum resulting in weak but distinctive PPV symptoms in susceptible cv. Sopernitsa.
Le point sur l'utilisation de sérums anti‐protéines non structurales pour l'étude de la sharka1
Authors: ADAMOLLE C. , QUIOT L. , BOUSALEM M. , BOEGLIN M. , QUIOT J. B.
Published: April 2008

Une voie possible pour la détection et la caractérisation des souches du plum pox potyvirus (PPV) peut être l'utilisation de sérums préparés contre des protéines non structurales, en particulier la protéine des inclusions cylindriques (CIP) et la protéine ‘a’ des inclusions nucléaires (NIaP) qui induisent des inclusions volumineuses dans les cellules infectées. Ces deux types d'inclusion ont été purifiés à partir de plants de Pisum sativum infectés par le PPV. Des antisérums ont ensuite été préparés contre leur monomère respectif. Pour la détection de l'infection, des essais comparatifs de tests ELISA montrent que, malgré une optimisation des tests utilisant les antisérums des protéines non structurales du PPV sur Prunus, l'antiserum dirigé contre la capside du sérotype D demeure, actuellement, le plus performant pour une détection de la virose en verger. Cependant, les sérums anti‐protéines non structurales se sont révélés utilisables pour des applications utilisant d'autres techniques comme, par exemple, la détection et la localisation tissulaire des protéines grâce à l'immuno‐empreinte. Ces sérums, qui ont présenté en électroimmunoblot une bonne spécificité pour le PPV et une grande polyvalence vis‐à‐vis des isolats de PPV testés, ont permis de constater que, contrairement à la sous‐unité capsidiale, les sous‐unités de CIP et de NIaP ne présentaient pas, entre souches, de difference de mobilitéélectrophorétique.
Transmission of plum pox potyvirus in Spain1
Authors: AVINENT L. , DE MENDOZA A. HERMOSO , LLÁCER G.
Published: April 2008

Transmission tests were conducted in the laboratory to determine which are the aphid species responsible for the great natural spread of plum pox potyvirus (PPV) observed in the field in Spain. Woody hosts were used in these tests and different transmission techniques were compared. The aphid species tested were Myzus persicae, Aphis gossypii, A. spiraecola, A. fabae, Hyalopterus pruni and Brachycaudus prunicola. Although the transmission rates obtained were, in general, quite low, it can be stated that, except for B. prunicola (pending confirmation of results), all species tested transmitted PPV under the conditions of the trial.
Current status of sharka disease in Puglia (Italy) and implementation of an eradication programme1
Authors: DI TERLIZZI B. , DIGIARO M. , SAVINO V.
Published: April 2008

Plum pox potyvirus (PPV) was introduced into Puglia (IT) a few years ago with infected propagative material coming from nurseries outside the region. Infections were detected in commercial plum and apricot orchards, but not in local nurseries. Extensive surveys were carried out in young apricot, plum and peach orchards to assess the distribution, incidence and spread of PPV infections, with a view to possibly enforcing an eradication programme. Surveys were based on visual inspections of about 300 commercial orchards and nurseries (covering an area of more than 550 ha) in the whole of Puglia, by ELISA and IBM tests, and by biological testing on GF305 of field samples. A total of 23,000 plants were individually checked by ELISA and IEM. The eradication involved 13 plum (35 ha) and 2 apricot (5 ha) orchards showing different levels of PPV infection. Six of the plum plantings showed infection exceeding 30% and were completely uprooted; in the remaining orchards, infection did not exceed 10% and uprooting was limited to infected trees. PPV was never detected in peach. The high incidence of PPV in some plum orchards was due to the heavy initial contamination of propagating material. Secondary virus spread was monitored in apricot orchards and found to occur at a low rate.
Approaches to pathogen‐mediated resistance breeding against plum pox potyvirus in stone‐fruit trees1
Authors: DA CÂMARA MACHADO A. , KNAPP E. , PÜHRINGER H. , SEIFERT G. , HANZER V. , WEISS H. , KATINGER H. , DA CÂMARA MACHADO M. LAIMER
Published: April 2008

In a programme for developing systems which allow the transfer of foreign genes into apricot cultivars, we have tested cotyledons of immature embryos, somatic embryos and leaf discs. Apricot plants have been transformed, and then regenerated, with Agrobacterium tumefaciens strain LBA 4404 containing various binary plasmids: pBinGUSint, carrying the marker gene β‐glucuronidase (GUS), and pBinPPVm, carrying the coat‐protein gene of plum pox potyvirus (PPV). The marker gene GUS was used for visual evaluation of the efficiency of the transformation system. The coat‐protein gene was used in the hope of introducing coat protein‐mediated resistance to one of the most important stone‐fruit pathogens in Europe and the Mediterranean area.
Production of plants of Nicotiana benthamiana and Prunus domestica transgenic for plum pox potyvirus coat protein, and demonstration of PPV resistance in transformed N. benthamiana1
Authors: RAVELONANDRO M. , SCORZA R. , CALLAHAN A. , CORDTS J. , MONSION M. , FUCHS M. , DELBOS R. , BACHELIER J. , GONSALVES D. , DUNEZ J.
Published: April 2008

Leaf discs of Nicotiana benthamiana plants were transformed with Agrobacterium tumefaciens and transgenic plants expressing plum pox potyvirus (PPV) coat protein (CP) were generated. Homozygous R2 progeny from these plants were inoculated with PPV. Plants were scored for the appearance of symptoms and tested for infection by DAS‐ELISA. Various levels of resistance were obtained after an initial stage in which PPV was able to multiply in all the transgenic plants. Within 2–3 weeks after inoculation, the transgenic resistant plants fully recovered from virus infection. Conversely, control and susceptible transgenic lines developed severe symptoms and high virus titres. Prunus domestica (plum) was transformed by inoculating hypocotyl slices with A. tumefaciens containing a binary plasmid which included the NPTII, GUS, and PPV CP genes within its T‐DNA region. Transgenic shoots were rooted and established in the glasshouse. Analysis of selected transformants by PCR showed that the engineered foreign genes had been integrated, including that for PPV CP. Histological assays on young leaves of these putative transformants gave a positive reaction. This suggests that all genes transferred are expressed in these transformed plums.
Une souche nécrogène du plum pox potyvirus provoque un dépérissement sur certains cultivars de pêcher1
Authors: ADAMOLLE C. , BOEGLIN M. , LABONNE G. , CANDRESSE T. , QUIOT J. B.
Published: April 2008

Une souche du plum pox potyvirus, PPV. SP, collectée dans un verger de pêcher du sud‐est de la France, a été sélectionnée après transmission par Myzus persicae et maintenue sur Prunus persica GF305. L'étude de la vitesse de migration de la sous‐unité de la protéine capside en électro‐immunoblot, critère de différenciation efficace des souches et isolats de PPV, a permis de classer cette souche dans le sérogroupe M de Kerlan & Dunez. Ce résultat a été confirmé par PCR sur la base d'un polymorphisme de restriction du fragment amplifié de cette souche par rapport à des souches de référence. Cependant, la souche PPV. SP se différencie de la souche M, ainsi que des isolats du sérogroupe D, dans l'extériorisation de la maladie. En effet, sur certains cultivars de pêcher, nous avons observé des symptômes foliaires caractérisés par des éclaircissements très forts des nervures secondaires et principales, qui rapidement évoluent en nécroses. Des chutes précoces de ces feuilles, observées dès le mois de mars, entraînent un dépérissement de l'arbre. Ce type de souche est collecté principalement sur pêcher bien qu'étant capable d'infecter l'abricotier. Par ailleurs, les observations effectuées en conditions naturelles sur la vitesse de propagation de la maladie suggérent que l'épidémie évolue trés rapidement dans les vergers de pêchers contaminés par cette souche.
Utilisation de la technique d'immunoempreinte pour l'étude de la résistance à la sharka chez les Prunus1
Authors: DICENTA F. , AUDERGON J. M.
Published: April 2008

La localisation du plum pox potyvirus (PPV) dans les tissus végétaux peut fournir une information intéressante sur les mécanismes de résistance de la plante à ce virus. Elle a été suivie par immunoempreinte, technique immunoenzymatique qui permet la localisation de l'enveloppe protéique (capside) du PPV dans les tissus de l'abricotier. Neuf cultivars d'abricotier présentant des niveaux de sensibilité différents à la maladie ont étéétudiés: Colomer, Screara, Tirynthe, Bebeco, Manicot, Henderson, Stark Early Orange, Stella et Harcot, ainsi que deux indicateurs sensibles à la maladie: le pêcher GF305 et Nicotiana benthamiana. L'analyse a porté sur des échantillons de feuilles, de tiges et de racines, inoculés ou non. Les résultats traduisent les différences de localisation du virus à l'intérieur des tissus et selon les espèces. La technique semble adaptée à l'étude de la sensibilité variétale en relation avec les mécanismes de résistance.
Evaluation of peach and nectarine cultivars in Bulgaria for their resistance to plum pox potyvirus
Authors: GABOVA R.
Published: April 2008

In spring and summer 1989, it was established that plum pox potyvirus (PPV) was present in certain peach cultivars in Bulgaria. At the same time, we started to investigate the distribution of PPV in naturally infected 4–5 year‐old peach and nectarine cultivars and hybrids in order to optimize PPV detection. Over 160 peach and nectarine cultivars and hybrids were evaluated. In about 40% of the genotypes, typical plum pox symptoms were observed. The latter were estimated and divided into groups depending on their susceptibility to PPV. Observations were made on the population density of seven aphid species established in the peach orchards. Five proved to be vectors of the virus. Myzus persicae was the vector that played the main role in spreading the virus on peach.
Breeding for resistance to plum pox potyvirus in the Czech Republic1
Authors: POLÁK J.
Published: April 2008

Breeding for plum cultivars resistant to plum pox potyvirus (PPV) is in progress in the Czech Republic, while projects for apricot and peach have started in 1991. The aim is to create an assortment of apricot and peach cultivars for northern regions of Europe in which PPV is widely distributed.
Assessment of varietal reactions to potato wart (Synchytrium endobioticum) in Germany
Authors: LANGERFELD E. , STACHEWICZ H.
Published: April 2008

A key for official assessment of potato cultivars for their resistance to Synchytrium endobioticum (potato wart) is presented. The margin between resistant and susceptible reactions is determined solely by the intensity of necrosis. Low numbers of ripe wart sori can be tolerated, if substantial necrosis occurs simultaneously. The key is a combination of the testing procedures of the two former German States and has been officially applied in Germany since 1992.
The Mediterranean fruit fly, Ceratitis capitata, a major pest of citrus in Israel, its regulation and control
Authors: ROSSLER Y. , CHEN C.
Published: April 2008

In order to export citrus and subtropical fruits, Israel has to regulate and control Ceratitis capitata, to ensure that harvested fruits are free from the pest. Legislative provisions allow the establishment of a centralized Control Programme. Monitoring and control operations are carried out by a central unit, funded by growers and subsidized by the Ministry of Agriculture. Monitoring in orchards is performed with trimedlure traps. Control is by aerial spraying with malathion bait. The Inspection Service verifies the absence of C. capitata in fruits for export. When required, the fruits may also be subject to a post‐harvest cold treatment, on shipboard (USA) or on shore (Japan).
Ecology of Xiphinema vuittenezi and Xiphinema pachtaicum in vineyards of north‐east Croatia1
Authors: SAMOTA D. , IVEZIC M. , RASPUDIC E.
Published: April 2008

During a 3‐year field study on two vineyards of north‐eastern Croatia, the qualitative and quantitative composition as well as the vertical dynamics of Xiphinema spp. were determined each month. The greatest number of fertile X. vuittenezi females was noted in August‐September at a soil moisture of 18–20%. The greatest number of larvae of this species was determined in September‐October in a temperature range of 14–18°C and soil moisture of 18–22%. The development cycle of X. vuittenezi lasts about 24–33 months under natural conditions and that of its larval stages 3–8 months. The nematodes of this species are susceptible to high temperatures (above 20°C) and drought (under 13%). The greatest number of fertile females of X. pachtaicum was determined in July at a soil temperature of 20–24°C, absolute soil moisture of 16–20%. The greatest number of larvae was noted in September‐October at a soil temperature of 16–21°C and soil moisture of 13–23%. The development cycle of X. pachtaicum in field conditions lasts about 12–13 months and that of the larval stages 2–3 months. This species demonstrated reduced activity at soil temperatures under 10°C and at soil moisture under 13%; larvae were less active than females at temperatures over 20°C. On the basis of the results obtained, it is suggested that sampling of vineyards to determine the distribution and population density of the two Xiphinema spp. should be performed at depths down to 50 cm in spring and autumn, which are also the most favourable times for nematicide application.
Nematodes of food legumes in the Mediterranean Basin1
Authors: GRECO N. , DI VITO M.
Published: April 2008

Several endoparasitic nematodes have been reported on leguminous plants in the Mediterranean area. The most widespread are the root‐lesion nematodes Pratylenchus mediterraneus, P. penetrans and P. thornei. Symptoms induced by these nematodes usually are not very impressive, but 50% yield loss of chickpea may occur. Among root‐knot nematodes, Meloidogyne artiellia is associated with severe yield losses of chickpea in Italy, Spain and especially Syria. Tolerance limits of 0.14 and 0.02 of this nematode per ml soil are reported for winter and spring‐sown chickpea, respectively. Meloidogyne incognita and M. javanica can be noxious to French bean and cowpea in sandy soil. The cyst nematode Heterodera goettingiana reduces yields of pea, broad bean and vetch when its population densities exceed 0.5, 1, and 2.1 eggs per g of soil, respectively. Heterodera ciceri occurs in northern Syria and Turkey and is responsible for economic yield losses of chickpea and lentil in fields infested with more than 1 or 2.5 eggs per g of soil, respectively. Pea and grass pea also suffer from infestation of this nematode. The stem and bulb nematode Ditylenchus dipsaci causes severe decline of broad bean, pea and probably lentil during wet seasons. Other nematodes, although present in moderate numbers, appear to have little importance.
Root‐knot nematodes (Meloidogyne spp.) in Hungary1
Authors: AMIN A. W.
Published: April 2008

During a routine survey which was conducted in three successive years, 1990–1992, in southeastern Hungary, it was found that Meloidogyne spp. are common on a wide host range in fields, glasshouses and polythene tunnels, especially in sandy soil between the Danube and Tisza rivers. Meloidogyne incognita, M. incognita acrita and M. arenaria were recorded to be the most important in glasshouses (at Hódmezóvásárhely, Csongrád, Mindszent, Fábiánsebestyén, Kistelek, Balástya, Szatymaz, Bordány, Mórahalom, Szeged, Apátfalva and Szegvár); M. hapla was found to be the most important species in the field (at Hódmezóvásárhely, Makó, Szeged, Szatymaz, Szentes, Domaszék, Mórahalom, Asotthalom, Bordány, Ulés, Zsombó, Balástya, Kistelek, Csanytelek, Forráskút and Rúzsa). M. thamesi was detected in certain cultivated plants and weed hosts (at Kistelek, Balástya, Rúzsa, and Gyula). Besides the cultivated plants, 41 weed plants, belonging to 34 genera in 22 families, were also found to be hosts for root‐knot nematodes in fields and glasshouses. Meloidogyne naasi was found for the first time in Hungary on some grass hosts.
The main parasitic nematodes on agricultural crops in Albania and their control1
Authors: JOVANI V.
Published: April 2008

From studies carried out on soil and root samples from the different agricultural crops in Albania, the following nematode genera have been detected: Meloidogyne, Ditylenchus, Tylenchulus, Globodera, Heterodera, Xiphinema, Pratylenchus, Helicotylenchus, Paratylenchus, Longidorus and Rotylenchus. The commonest species of nematodes are: M. incognita, X. pachtaicum, D. dipsaci, D. destructor, T. semipenetrans, G. rostochiensis, H. schachtii and P. penetrans. Trials on chemical control of root‐knot nematodes on tomato have indicated that methyl bromide (500 kg ha‐1) and dichloropropane/dichloropropene are still the best chemicals. Certification of garlic crops, with selection of bulbs before and after sowing, has increased garlic yields to 5–10t ha‐1. Chemical methods to control D. dipsaci are not usually economical.
Identification of plant‐parasitic nematodes by PCR amplification of DNA fragments1
Authors: DE GIORGI C. , SIALER M. FINETTI , DI VITO M. , LAMBERTI F.
Published: April 2008

A study concerning the detection and characterization of a DNA fragment from plant‐parasitic nematodes to be used as a molecular marker for the identification of different nematodes is described. A fragment of DNA, which is known to consist of a variable region flanked by two conserved regions, has been studied by using PCR amplification. A portion of about 600 nucleotides at the 5’end of the larger rRNA gene has been amplified in different nematodes, using heterologous primers which hybridize with the conserved regions. The results obtained clearly indicate that the same primers can be used for the amplification of this segment in nematodes of different species and of different genera: Meloidogyne artiellia, M. incognita, Xiphinema index, X. diversicaudatum and Globodera pallida. The amplified regions have been partially sequenced. The nucleotide sequences have been analysed by comparison with the published sequence of Caenorhabditis elegans.
Potential for identification of quarantine nematodes by PCR1
Authors: VRAIN T. C. , McNAMARA D. G.
Published: April 2008

Quarantine nematodes often pose particular problems of precise identification. Restriction fragment length differences in some fragments of DNA can easily separate species and races of nematodes that are difficult to identify by morphometrics. Amplification of DNA sequences allows accurate identification using one individual or very few nematodes of any stage. The DNA amplification is simple, and the pattern of DNA restriction bands are easily read, without training in molecular biology. It is suggested that international cooperation is needed in order to build up banks of DNA restriction patterns characteristic of each quarantine nematode species.
Plant‐parasitic nematodes associated with pine trees in Bulgaria1
Authors: PENEVA V. , CHOLEVA B.
Published: April 2008

Literature data on the nematode fauna of Pinus spp. in Bulgaria are summarized. 48 plant‐parasitic nematodes have been reported so far associated with six pine species and a variety of one of these species. In the course of the present study of pine nematode fauna in Rila and Rhodope mountains, Crossonema menzeli, Criconemella xenoplax, Bursaphelenchus sp., Longidorus vineacola, L. leptocephalus, Longidorus sp. and Trichodorus similis were found. Morphological data on some of the species studied are given. The males of L. leptocephalus was more common than the females. L. leptocephalus and Bursaphelenchus sp. are new geographical records. Pinus sylvestris is a new plant host for C. menzeli and L. leptocephalus.
Résistance des arbres fruitiers à noyau aux nématodes à galles: étude du modèle Prunus cerasifera1
Authors: ESMENJAUD D. , SALESSES G. , MINOT J. C. , VOISIN R. , BONNET A.
Published: April 2008

La résistance des arbres fruitiers aux nématodes à galles est étudiée sur le prunier myrobalan, Prunus cerasifera. La mise en évidence d'une variabilité génétique intraspécifique (clones sensibles à très résistants) et les diverses possibilitès de multiplication végétative de cette espèce en font un bon modèle d'étude pour caractériser le phénomène de résistance chez une plante pérenne. Selon les objectifs de l'étude, le matériel végétal utilisé se présente sous forme de boutures ligneuses racinées ou de jeunes plants issus de micropropagation in vitro. Le programme en cours aborde le déterminisme génétique vis‐à‐vis d'une population de Meloidogyne arenaria, le spectre de résistance vis‐à‐vis des autres populations et espèces afin de prendre en compte la variabilité intraspécifique de leur pathogénicité, les variations de la résistance en fonction de la pression d'inoculum et de la température, les mécanismes de résistance, et les interactions avec d'autres ravageurs ou maladies du sol tels que les Pratylenchus spp. ou le crown‐gall.
Control of root‐knot nematodes (Meloidogyne spp.) in Hungary1
Authors: BUDAI Cs.
Published: April 2008

Under Hungarian climatic conditions, root‐knot nematodes, and other phytoparasitic nematodes, generally cause damage in certain plant growing areas. These pests are present in glasshouses throughout the country. In the field the nematodes occur in sandy soil in the vegetable‐growing areas of southern and central Hungary. The following species of root‐knot nematodes have so far been reported to occur in Hungary: Meloidogyne incognita, M. arenaria, M. hapla, M. javanica, M. incognita acrita, M. thamesi and M. naasi. There are 10 specific nematicides registered for nematode control in the country. These chemicals are mainly applied in glasshouses where their use produces most economic return. Nematoderesistant cultivars are only available in the case of tomato. The nematodes cause the heaviest damage on glasshouse cucumber.
Severe attack of Microsphaera platani on Platanus orientalis var. cretica in Crete (Greece)
Authors: VAKALOUNAKIS D. J. , KLIRONOMOU E.
Published: April 2008

The occurrence of a severe attack of Microsphaera platani on Platanus orientalis and on P. orientalis var. cretica in Crete is reported for the first time.
Situation of the Asian form of gypsy moth (Lymantria dispar) in Russia and in the world
Authors: SAVOTIKOV I. F. , SMETNIK A. I. , ORLINSKII A. D.
Published: April 2008

Lymantria dispar occurs in Russia in at least two forms, the European form in European Russia (and also in western Europe) and the Asian form in the Russian Far East (and other far eastern countries). During an outbreak in the Russian Far East in the early 1990s, egg masses of L. dispar were found on Russian ships sailing from the Far East ports to the west coast of North America. Larvae blown from such ships may have been responsible for outbreaks of the Asian form of L. dispar in western Canada and USA. As a result, a Russian‐American lymantriid monitoring programme was set up, using pheromone and light traps to follow the occurrence and flight of Lymantria spp. around ports of the Russian Far East and in adjacent forest areas. These have shown a general decline in populations since 1992.
Plant pest risk information system (PPRIS) for USDA‐APHIS: design of a functional prototype
Authors: COHEN S. D. , CHANG L. W. , GRIFFIN R. L. , ORR R. L.
Published: April 2008

The Plant Pest Risk Information System (PPRIS) is a computerized decision‐support system for plant pest risk assessment in the USA, being developed for use by personnel of the US Department of Agriculture's (USDA) Plant Protection and Quarantine, Animal and Plant Health Inspection Service (APHIS). PPRIS is being designed to retrieve information from such diverse sources as: EPPO PQ database, USDA‐Agricultural Research Service's (ARS) Fungi on Plants and Plant Products database, bibliographic databases on compact disc media, on‐line INTERNET databases and risk assessment documents. PPRIS will offer access to a wide variety of risk assessment processes. A PPRIS evaluation prototype was created in Visual Basic ver. 3.0 operating in a Windows 3.1 environment. EPPO‐PQ and ARS‐Fungi databases were imported and stored in ORACLE ver. 6.0. Query functionality of the prototype was tested by retrieving information from the two internal ORACLE databases. The PPRIS evaluation prototype provides interfaces to the CABPEST bibliographic compact disc and to communication software for on‐line database searches. Three risk assessment processes were incorporated into the evaluation prototype: the decision sheet, generic risk assessment and enhanced hazard identification. The evaluation prototype also includes access to Wordperfect for Windows through the Windows Program Manager for storage and retrieval of risk assessment documents.
Phytophthora root disease of alder in Britain
Authors: GIBBS J. N.
Published: April 2008

A root disease of common alder caused by Phytophthora sp. is widespread in southern Britain. It is estimated that more than 20 000 trees are seriously affected.

Une infection racinaire due àPhytophthora sp. est largement disséminée dans le sud de la Grande‐Bretagne. Plus de 20 000 arbres sont estimés gravement atteints.
Plant quarantine significance of dwarf bunt of wheat to China
Authors: ZHANG Z. , ZHANG C. R. , WANG Z. Z.
Published: April 2008

The adaptability of Tilletia controversa was studied in particular relation to China, where wheat is cultivated under various climatic conditions. Teliospore germination is closely influenced by temperature, light and soil humidity. Establishment of T. controversa depends on: (1) persistent low temperature (0–10°C) within the surface layer of the soil, in combination with adequate soil moisture; (2) presence of seedlings of susceptible wheat cultivars, especially in the early stage of tillering before or during overwintering. The climatic conditions of various wheat‐growing areas in China were compared with the results obtained in this study, and areas of prevalent damage and of marginal damage were predicted. It was concluded that T. controversa presents a considerable hazard to China if it accidentally enters.
Survival of Polymyxa betae during processing of vegetables and sugarbeet
Authors: DICKENS J. S. W. , WRIGHT A. J. , REED P. J.
Published: April 2008

Samples of effluent were taken at various stages in a range of waste‐water treatment systems from seven sugarbeet factories and 14 vegetable processors and tested by a seedling‐baiting method. None of the systems examined appeared completely to remove Polymyxa betae, the fungal vector of beet necrotic yellow vein furovirus, the cause of rhizomania disease of sugarbeet. In laboratory experiments, neither anaerobic conditions, raising the pH to 12 nor treating with peracetic acid had any discernible effect on P. betae viability. It is concluded that there is a risk that rhizomania disease could be spread by waste water from processing infected sugarbeet or vegetables from infested land, although there is some evidence that this risk is reduced where systems involving extensive settlement are used.
A diagnostic network for the EPPO region 1
Authors: VAN HALTEREN P.
Published: April 2008

The occurrence of the quarantine pest Thrips palmi in The Netherlands in 1992 and the difficulties encountered in enforcing legal eradication measures have stimulated discussion concerning a possible network of diagnostic services in Europe. Official services find it increasingly difficult to evaluate and adopt the latest diagnostic techniques produced by research institutes and universities. It is proposed to create international discipline‐oriented working groups to prepare draft identification methods for the official EPPO and EU quarantine pests. These draft methods could be harmonized by the EPPO Panel on Diagnostics and approved by EPPO Council. This is a two‐sided sword: internationally agreed identification methods are produced and a diagnostic network comes into being at the same time.
Le diagnostic sérologique des champignons: quelques exemples pour une stratégie d'utilisation 1
Authors: SPIRE D.
Published: April 2008

Le principal problème posé par les méthodes d'immunodétection pour les champignons phytopathogènes est liéà la présence de très nombreuses protéines fongiques, dont certaines ne sont pas spécifiques de l'espèce. Aussi, chaque préparation fongique contient un nombre important d'antigènes parmi lesquels seuls quelques‐uns sont intéressants pour un diagnostic. Par quelques exemples, nous voulons illustrer les méthodes employées à l'INRA Versailles, où il a été décidé de concentrer les efforts sur une meilleure compréhension de la variabilité des protéines de champignons et d'utiliser des anticorps polyclonaux comme préliminaires à la production d'anticorps monoclonaux. Dans le cas de Peronospora viciae sur semences de pois, ou de Verticillium dahliae sur boutures de pélargonium, il n'y a qu'un pathogène du même genre présent dans la plante. Aussi, une grande spécificité n'est pas nécessaire, et il est facile de produire un bon antisérum détectant le mildiou du pois de semence ou V. dahliae dans les plantes, même si d'autres mildious ou Verticillium réagissent avec l'antisérum. Si deux espèces proches d'un point de vue taxonomique sont présentes sur la même plante, par exemple Sclerotinia sclerotiorum et Botrytis cinerea sur pétales de colza, il est nécessaire d'éliminer les protéines non spécifiques par différents types d'absorption croisée. Si différentes espèces fongiques du même genre infectent la même plante, le problème est plus compliqué. Etudier et choisir des protéines spécifiques, capables de distinguer les champignons, devient nécessaire.
Detection of strawberry black spot (Colletotrichum acutatum) with monoclonal antibodies 1
Authors: COOK R. T. A. , BARKER I. , BREWER G. , CROSSLEY S. , FREEMAN S. , LANE C.
Published: April 2008

Baiting with apple fruit and stimulation of sporulation with paraquat are sensitive tests currently used on strawberry planting/propagating material for the detection of Colletotrichum acutatum. A monoclonal antibody/ELISA technique could make testing shorter and easier. Several monoclonal antibodies distinguished C. acutatum in vitro; one recognized 45 out of 48 isolates believed to be C. acutatum, but not 18 out of 19 typical of closely related C. gloeosporioides. A less specific monoclonal antibody reacted positively with 66 out of 67 Colletotrichum isolates, indicating it was genus‐specific. The antigen was mainly associated with conidia. A dot‐blot test using PALL Biodyne membrane gave qualitative results more quickly and simply than ELISA, reducing time taken from 24 to 3 h. Specific monoclonal antibodies distinguished C. acutatum from C. gloeosporioides on strawberry petioles, but were less sensitive than either plating or paraquat tests, detecting only eight out of 50 potential positives compared with at least 30 out of 50 with the other tests. An immunofluorescence technique confirmed that conidia were the main source of antigen. A specific monoclonal antibody also reacting to mycelium was produced.
Detection of benzimidazole resistance in Rhynchosporium secalis using allele‐specific oligonucleotide probes 1
Authors: WHEELER I. , KENDALL S. , BUTTERS J. , HOLLOMON D.
Published: April 2008

Benzimidazole fungicides are important mixture components in strategies to combat resistance in Rhynchosporium secalis as well as other plant pathogens. This strategy has recently been threatened by the detection of benzimidazole resistance in field strains of R. secalis. To evaluate the significance of this resistance, and to monitor its spread, a rapid and accurate method for identifying resistant alleles is needed. Consequently, we have developed a method for detecting benzimidazole resistance based on the hybridization of allele‐specific oligonucleotide (ASO) probes to PCR‐amplified DNA fragments.
Immunofluorescence colony‐staining (IFC) as a concept for bacterial detection in quality testing of plant materials and ecological research 1
Authors: VAN VUURDE J. W. L. , KASTELEIN P. , VAN DER WOLF J. M.
Published: April 2008

Immunofluorescence colony‐staining (IFC), as a concept in bacterial detection, has developed during the past decade, providing several new options for the study of culturable plant‐associated bacteria: (1) in situ detection of target colony‐forming units on or in plant parts, such as on roots or in stem sections; (2) selective isolation of cross‐reacting bacteria for research on the improvement of the reliability of serological detection systems; (3) distinction between culturable and non‐culturable cells; (4) simultaneous detection of different target bacteria using different fluorescent markers and a dual fluorochrome‐filter system. IFC‐positive colonies can be directly identified by isolation or PCR, which makes it easier to recognize false positive results. The use of IFC for the selective isolation of cross‐reacting bacteria forms a major tool for the further improvement of the specificity of IFC and serological assays.
Action of phthalocyanine on the exopolysaccharides, detectability and survival of Clavibacter michiganensis subsp. sepedonicus1
Authors: LEWOSZ J. , PASTUSZEWSKA T.
Published: April 2008

Phthalocyanine displays high affinity towards various polysaccharides and bacterial exopolysaccharides. A 0.01‐0.02% aqueous solution caused immediate agglutination and loss of infectivity of mucoid strains of Clavibacter michiganensis subsp. sepedonicus. Non‐mucoid strains survive in the presence of phthalocyanine due to impaired exopolysaccharide production. Agglutination and killing of mucoid phenotypes offers a better opportunity for revealing the presence of non‐mucoid phenotypes, which can avoid detection due to slower growth rate and lack of the serologically recognizable epitopes on exopolysaccharides. Phthalocyanine can be used to identify C.m. sepedonicus among other phytopathogenic bacteria and to destroy ring‐rot bacteria on the surface of contaminated tubers or other objects.
Use of ELISA for detection of Clavibacter michiganensis subsp. michiganensis in tomato 1
Authors: KRÄMER I. , GRIESBACH E.
Published: April 2008

A DAS‐ELISA method has been developed to detect the causal agent of bacterial canker of tomato, Clavibacter michiganensis subsp. michiganensis. The high sensitivity of the test can be attributed to antibodies which are produced against soluble antigens (extracellular products). The most suitable part of the tomato plant for reliable detection of the bacterium is the lower stem region. It is possible to differentiate heavy and weak symptom expressions by ELISA. The ELISA procedure also allows detection of C.m. michiganensis in symptomless tomato plants. Furthermore, the bacterium has been detected in tomato seeds harvested from infected plants.