bluuebunny/crossref_metadata_2025 huggingface dataset:
Recherche et caractérisation de sols résistants aux Pythium spp. en Amazonie brésilienne1
Authors: LOURD M. , BOUHOT D.
Published: April 2008

Aux environs de la ville de Manaus (Amazonie brésilienne), les sols sont localisés dans deux écosystèmes: ‘terra firme’ recouverte de foret vierge ou cultivée et ‘varzea’, zones submergées chaque année et cultivées. 160 échantillons de sol ont été prélevés dans ccs deux zones, puis analysés afin de déterminer leur capacité de fonte des semis, causée par les Pythium spp.; 76 de ces sols semblaient non infestés, ou ne l'étaient que faiblement. Afin de déterminer leur réceptivité vis‐à‐vis des Pythium spp., les 76 sols ont été inoculés avec 10% d'un sol infesté naturellement, et la capacité d'infection a étéévaluée aprés des incubations de 4, 8, 12 et 16 semaines par tests biologiques sur jeunes plants de concombre. L'aptitude à supprimer les Pythium spp. n'est apparue que dans les écosystèmes ‘terra firme'et non dans les ‘varzeas’ submergés. La fréquence des sols pouvant supprimer la maladie semblait décroitre en fonction de la mise en culture: 82% dans les sols de foret vierge; 67% dans les sols de pépinières forestiéres; 53% dans les forets gérées; 31% dans les sols forestiers mis en culture avec des cultures variées; 7% dans les sols forestiers mis en culture et portant des cultures maraichères. On a constaté trois types d'aptitude à supprimer les Pythium spp. aprés inoculation des sols: (1) résistance apparaissant rapidement et se maintenant à un niveau élevé et constant (jusqu'à 16 semaines); (2) résistance initiate élevée, mais non durable; (3) résistance initialement faible, mais croissante avec le temps. Une partie de cette dynamique semble etre sous controle microbien. Le développement agricole autour de Manaus ainsi que les systèmes de culture intensifs peuvent rapidement modifier les écosystèmes microbiens des sols et nuire à leur capacité naturelle à supprimer les Pythium spp.
Evaluation of several antagonists and different methods of application against fusarium wilt of carnation1
Authors: GARIBALDI A. , BRUNATTI F. , GULLINO M. L.
Published: April 2008

Saprophytic Fusarium strains, isolated from Fusarium‐suppressive soils, have been tested in pot and glasshouse experiments in order to reduce soil colonization by Fusarium oxysporum f.sp. dianthi. The highest amount of antagonist inoculum tested (200 g m‐2) showed the best results in controlling carnation wilt. The antagonistic Fusarium strains showed good efficacy when applied by dipping rooted cuttings in conidial suspensions of the antagonists or by mixing inoculated wheat kernels or perlite + wheat bran with the soil. The effectiveness of the antagonistic Fusarium strains in reducing incidence of F.o. f.sp. dianthi was improved by combining chemical (benomyl, 20 g m‐2) with biological measures.
Utilisation d'antagonistes pour l'enrobage des semences: efficacité et mode d'action contre les agents de la fonte des semis1
Authors: GORDON‐LENNOX G. , WALTHER D. , GINDRAT D.
Published: April 2008

Le screening de 224 cultures microbiennes a fourni 17 souches de champignons, 5 bactéries et 1 actinomycète efficaces, en enrobage des semences, contre la fonte des semis de la betterave dans un sol contaminé par Pythium spp. en chambre climatisée. L'examen de ces 23 souches a permis de sélectionner Pseudomonas sp., Pythium oligandrum et Chaetomium globosum. Appliqués respectivement sous la forme de cellules bactériennes, d'oospores ou d'ascospores, les trois antagonistes ont présenté une efficacité constante contre Pythium ultimum. Sur les semences stockées, Pseudomonas sp. et P. oligandrum ont conservé leurs propriétés plusieurs mois, C. globosum pendant au moins 2 ans. Pseudomonas sp. et P. oligandrum protégeaient les betteraves contre P. ultimum et Phoma betae (contaminant les semences), mais pas contre Rhizoctonia solani. C. globosumétait efficace contre les trois pathogènes. Il était aussi actif contre P. ultimum et R. solani sur coton. Son efficacité contre Aphanomyces cochlioides sur betterave est à l'examen. Le mycoparasitisme de P. oligandrum, l'antibiose de C. globosum et Pseudomonas sp. ainsi que des dégradations aux hyphes des pathogènes par Pseudomonas sp. et C. globosum ont été observés in vitro.
Perspectives d'utilisation de Hansfordia pulvinata contre la cladosporiose de la tomate1
Authors: TIRILLY Y. , TRIQUE B. , MAISONNEUVE J.
Published: April 2008

La cladosporiose demeure l'une des principales maladies des cultures de tomate en serre car la lutte chimique reste peu satisfaisante. Elle est parfois naturellement ralentie par l'installation spontanée d'un hyperparasite de Fulvia fulva (syn. Cladosporium fulvum), Hansfordia pulvinata, antagoniste actif de l'agent pathogène. L'élaboration d'une méthode de lutte biologique a été envisagée. Une production industrielle de ce biopesticide est en cours de mise au point. En serres de production, 80% ou plus des taches de cladosporiose sont recouvertes par l'hyperparasite. Cependant, l'efficacité du controle est limitée par l'incapacité de H. pulvinataà entrer en contact avec F. fulva lors de sa phase biotrophe ainsi que par la faible autodissémination de l'hyperparasite. Un apport de phoséthyl‐Al (1.6 g l‐1) a amélioré l'efficacité de la méthode. Ce fongicide, compatible avec H. pulvinata, inhibe la germination des spores de F. fulva. Dans cette lutte intégrée, l'hyperparasite abaisse la pression d'inoculum du parasite et le fongicide limite les nouvelles contaminations. Au vu des premières expérimentations en serre, cette méthode pourrait etre préconisée en début d'attaque de cladosporiose et devrait réduire la fréquence des traitements, favorisant en cela une large lutte intégrée et l'emploi des auxiliaires.
Effect of soil solarization on the survival of fungal antagonists of Verticillium dahliae1
Authors: TJAMOS E. C. , PAPLOMATAS E. J.
Published: April 2008

Talaromyces flavus, a fungal antagonist of Verticillium dahliae, naturally occurring in clay loam artichoke fields or sandy loam olive groves, is able to survive following application of soil solarization. Survival was almost always linked to an increase in T. flavus populations detected in the rhizosphere of artichoke plants or olive trees with a verticillium wilt history as compared with the untreated control soils. It was evident that soil solarization resulted in the control of the disease in artichoke fields and the recovery of olive trees from V. dahliae infection. It was furthermore proved that solarization had a beneficial long‐term effect in controlling V. dahliae for a period of 2 or 3 consecutive years. This could at least partially be attributed to the activity of T. flavus in inhibiting the germination of microsclerotia or causing their death. Aspergillus terreus, another potential V. dahliae antagonist, was also found to survive and occasionally increase following the application of the technique.
The citrus nursery site approval program for burrowing nematode and its beneficial effect on the citrus industry of Florida
Authors: ESSER R. P. , O'BANNON J. H. , RIHERD C. C.
Published: April 2008

The nursery site approval program for spreading decline of citrus, caused by the burrowing nematode Radopholus similis1, is evaluated after 33 years of application in Florida (US). The economic benefits of the site approval program have far outweighed the costs engendered by the program. A site approval model is provided for use worldwide by regulatory agencies if similar pest problems are encountered.
In vitro evaluation of the antagonistic properties of Trichoderma spp. against Pyrenochaeta lycopersici and Phomopsis sclerotioides1
Authors: VANACHTER A. , VAN WAMBEKE E. , VAN ASSCHE C.
Published: April 2008

In vitro evaluation of the antagonistic properties of Trichoderma spp. against Pyrenochaeta lycopersici and Phomopsis sclerotioides was carried out, using two different methods: the cellophane‐agar plate method and the duaí culture method. With these methods, the direct interaction between pathogen and antagonist was demonstrated, showing very remarkable differences between the different isolates. Growth inhibition ranging from 20 to 100% was found. Proliferation in non‐sterilized soil was investigated for the isolates showing the most interesting antagonistic properties. A Belgian isolate of Trichoderma hamatum was found to be able to proliferate very well in soil and to maintain a high population density during the whole experimental period.
Antagonisme entre les Pseudomonas fluorescents et plusieurs pathovars de Pseudomonas syringae. Application comme méthode de lutte contre la moucheture bactérienne de la tomate1
Authors: COLIN J. E.
Published: April 2008

Deux Pseudomonas du groupe fluorescens‐putida,à forte activité inhibitrice vis‐à‐vis de bactéries phytopathogènes, ont été confrontéà une gamme de 23 pathovars de Pseudomonas syringae. lis ont confirmé leur activité antagoniste sur ces derniers germes. Deux essais réalisés dans des conditions normales de culture de plein champ ont démontré la potentialité de ces antagonistes comme moyen de lutte contre la moucheture bactérienne, due àP. syringae pv. tomato. Des travaux complémentaires ont montré que ľactivité antagoniste des deux germes inhibiteurs n'est pas semblable, ľun des deux agissant essentiellement par la production ďun sidérophore. Le mécanisme ďaction du second germe n'est pas déterminé.
Microbial control of plant diseases with Streptomyces spp.1
Authors: TAHVONEN R. T.
Published: April 2008

Light‐coloured Sphagnum fuscum peat is the substrate most widely used in glasshouses in Finland. A number of Streptomyces strains which are strongly antagonistic against a number of soil and seed‐borne fungal pathogens, both in vitro and in vivo, have been isolated from light‐coloured peat. Seed dusting with Streptomyces prevented or reduced damping‐off and foot‐rot disease caused by Alternaria brassicicola and Rhizoctonia solani on crucifers. Seed treatment slightly increased yields of cereals in fields experiments. Spraying the substrate with a suspension of Streptomyces reduced root diseases on cucumbers caused by Pythium, and in many cases successfully prevented fusarium wilt of carnations. A dry powder preparation has been made from the Streptomyces isolates, and applied at a dose of 5‐10 g kg‐1 in seed dusting, and 0.1‐10 g 100 m‐2 when spraying the substrate. The microbe was most effective in peat soil, although good results have also been obtained in fine sand and clay soils.
Large‐scale application of biological control of crown gall in Greece1
Authors: PSALLIDAS P. G.
Published: April 2008

Crown gall disease of cultivated plants, caused by Agrobacterium tumefaciens, constitutes a serious problem for the fruit tree, rose and grapevine nurseries in Greece. All three biotypes of A. tumefaciens exist in Greece. Biotypes 1 and 2 have a wide host range being responsible for the disease on fruit trees and roses while biotype 3 isolates have a narrow host range infecting grapevine only. All Greek isolates of biotype 1 and all but 3 isolates of biotype 2 were sensitive to biological control with the antagonistic bacterium A. radiobacter strain K84, but the biotype 3 isolates were insensitive to biocontrol. Experiments on the effectiveness of the method in artificial infections of seedlings as well as in naturally infested soils showed that the method is effective and can be applied without any risk of development of forms insensitive to biocontrol. The use of a lyophilized preparation of K84 with skim milk as suspending medium is recommended. The lyophilized antagonistic bacterium retains its activity and the final concentration (106 cfu ml‐) is adequate to protect treated plants from crown gall.
Lutte biologique contre les Meloidogyne au moyen du champignon prédateur Arthrobotrys irregularis1
Authors: CAYROL J. C.
Published: April 2008

Quatre critères essentiels doivent être retenus pour sélectionner un champignon prédateur comme agent de lutte biologique contre les nématodes: sa spécificité, ses exigences écologiques, son pouvoir compétiteur et son innocuité pour ľhomme et ľenvironnement. En les respectant, on a sélectionné le champignon Arthrobotrys irregularis, actif contre les Meloidogyne, qui est produit industriellement sous forme ďune culture mycélienne vivante sur un milieu à base de céréales cuites (nom commercial: S‐350). Il s'utilise à la dose de 140 g m‐2 par épandage à la surface du sol suivi ďun léger enfouissement. Ľapplication doit être faite un mois au moins avant la plantation pour que le mycélium ait le temps de bien coloniser le sol. Le champignon permet de contrôler des attaques moyennes ou légères de Meloidogyne. En cas ďattaque très forte, il ne permet la destruction des parasites qu'après 2 ou 3 ans et, dans la pratique, il est préférable de procéder ďabord à un traitement chimique qui détruit 70% des nématodes puis ďapporter ensuite le champignon pour éliminer les individus rescapés et établir dans le sol un équilibre biologique durable.
Revue de plusieurs années de recherche en Italie sur la lutte biologique contre les champignons telluriques avec Trichoderma spp.1
Authors: D'ERCOLE N. , NIPOTI P. , FINESSI L. E. , MANZALI D.
Published: April 2008

Des résultats encourageants ont été obtenus au cours de recherches de lutte biologique contre les pathogènes cryptogamiques du sol àľaide de Trichoderma spp. ľaction positive de ces antagonistes a étéétudiée sur les champignons (Fusarium moniliforme, Rhizoctonia solani et Pythium ultimum) responsables de la fonte des semis, de la pourriture des racines et de la pourriture précoce de la tige du maïs et du sorgho. Sur fraisier, les traitements avec Trichoderma spp. se sont révélés très satisfaisants contre les attaques de Botrytis cinerea sur fruits ainsi que contre le pied‐noir ďété après repiquage. En ce qui concerne la fusariose et la verticilliose de la tomate, ďexcellents résultats ont été obtenus pour la réduction des maladies et ľaugmentation des rendements. Les travaux pour combattre la pourriture du collet de la laitue (Sclerotinia minor) ont également donné de bons résultats. Les possibilityés de transposition dans la pratique de ces résultats, obtenus généralement en conditions ďinoculation artificielle, sont étudiées.
Influence de la fertilisation azotée sur la receptivityéďun sol au piétin‐échaudage, le développement de la maladie au champ et les populations de Pseudomonas fluorescents1
Authors: LUCAS P. , COLLET J. M.
Published: April 2008

Différents travaux montrent que le piétin‐échaudage est moins grave quand le blé reçoit une fertilisation azotée sous forme ammoniacale plutôt que sous forme nitrique. Les hypothèses avancées pour expliquer ce phénomène sont une réduction du pH de la rhizosphère, ayant un effet direct sur le développement du champignon, ou indirect par stimulation ďune partie de la microflore, ou encore une incidence de la forme ďazote sur la physiologie de la plante. Dans un essai conduit au champ, trois modalités expérimentales ont été combinées: cultivars, traitement fongicide de semences, fertilisation azotée. Les résultats présentés ici portent sur ce dernier facteur à deux niveaux (sulfate ďammonium ou ammonitrate). Deux notations, à partir de plantes prélevées au champ, ont renseigné sur ľévolution du piétin‐échaudage: seule la fertilisation azotée a eu un effet signiflcatif sur le développement de la maladie, le sulfate ďammonium réduisant de moitié la fréquence de plantes attaquées (15 contre 32%), sans diminuer la gravité des attaques. Parallèlement, des tests réalisés sur échantillons de sols prélevés en décembre, mars et mai, ont indiqué qu'à ces trois périodes les sols fertilisés avec du sulfate ďammonium étaient moins réceptifs que ceux fertilisés avec de ľammonitrate. Enfin, les analyses sur une fraction bactérienne de la microflore ont montré que les Pseudomonas fluorescents étaient quatre fois plus nombreux pour le sulfate ďammonium que pour ľammonitrate.
Predation et lutte microbiologique. Potentialités de ľassociation protozoaires‐microflore1
Authors: PUSSARD M.
Published: April 2008

Les connaissances acquises à propos des protozoaires dans le sol permettent de mieux comprendre ľinfluence de la predation sur la microflora. En présence de protozoaires, les populations bactériennes se maintiennent à un niveau relativement élevé pourvu que les bactéries aient la possibilityé de croître et de se multiplier. Dans ces conditions, la prédation s'accompagne ďune stimulation de ľactivite globale de ces populations. Protozoaires et bactéries sont en fait étroitement associés sur le plan fonctionnel. Vis‐à‐vis des champignons les protozoaires auraient une influence plutôt dépressive, soit directement en détruisant des propagules, soit indirectement en stimulant les bactéries antagonistes. Dans ce domaine, de nouvelles recherches s'imposent. Ces considérations doivent être prises en compte lors des interventions agronomiques ou biotechnologiques sur les communautés microbiennes complexes.
Rodent behaviour in relation to baiting techniques1
Authors: LUND M.
Published: April 2008

The use of poison baits is still the most important control method against commensal as well as field rodents. The baiting techniques used must be adapted to the ecology and behaviour of the target species. The various aspects of rodent behaviour influencing the effect of a control operation are discussed with emphasis on feeding behaviour, exploratory behaviour, neophobia, bait shyness, transporting, hoarding and territoriality. Advantages and disadvantages of sustained versus pulsed baiting techniques are discussed from a behavioural point of view.
The efficacy of two permanent poison‐baiting measures againstMus domesticusliving in farm buildings in the UK1
Authors: ROWE F. P. , SWINNEY T.
Published: April 2008

The effectiveness of two poison bait formulations was examined in trials against infestations ofMus domesticusin farm buildings. Treatment was extensive on each of four farms, covering all buildings and lasting 1 year. In the four trials, bait containing calciferol and warfarin in combination, or difenacoum was used. Mouse infestation level was monitored, using the mark‐recapture trapping technique, before poison‐baiting was begun and every 6 weeks thereafter. Poison bait consumption was high initially and mouse numbers were substantially reduced on all four farms within 6 weeks. Subsequently, the difenacoum treatments were the most effective in keeping infestation levels extremely low. Mice still resident when the treatments were terminated were removed by live and kill traps. Laboratory feeding tests were conducted on the live‐caught survivors; all animals died after consuming poison bait of the kind used in the trials. Additional live‐trapping, 6 months and 1 year later, produced evidence of recolonization and of renewed population growth. It is concluded that sustained control effort is needed to prevent the build‐up ofM. domesticusnumbers in farm buildings.
Observations effectuées au cours d'un essai de lutte contre Apodemus sylvaticus en semis de betteraves1
Authors: MOENS R.
Published: April 2008

L'attaque de mulots sur les semences de betteraves a été suivie en laboratoire et en plein champ. Des observations en cage ont démontré que le rongeur s'attaque aux graines de betteraves à partir du stade 00 (graines sèches) jusqu'au stade 06 (développement de la tigelle dans le sol) avec un maximum pendant le ramollissement de la graine (stades 01 et 02) et le début de la germination (stade 03). L'attaque s'arrête au cours de l'allongement, quand les cotylédons perdent leur contenu farineux (stade 07). Sur le terrain il fut constaté que le rongeur, après avoir détruit 20% d'un premier semis, n'a plus attaqué un second semis, lorsque des postes d'appâtage de noisettes traitées à la chlorophacinone (30 ml du Caïd huileux par kg) ont été installés sur les bords du champ. Les appâts ayant fourni aux mulots une nourriture de substitution, ceux‐ci ont renoncéà rechercher les semences dans le sol. Quant à l'effet toxique du rodenticide, celui‐ci semble insuffisant et trop tardif pour protéger les semis.
Assessing the impact of rodenticides on the environment1
Authors: BROWN R. A. , HARDY A. R. , GREIG‐SMITH P. W. , EDWARDS P. J.
Published: April 2008

As with any pesticides, it is recommended that the environmental safety of a rodenticide is assessed in a stepwise manner, i. e. from basic laboratory studies on chemical behaviour and toxicology, through more detailed, specifically designed, studies of the compound's potential environmental hazard, to field experiments if they are shown to be necessary by the results of the lower tier studies. Following the release of the rodenticide onto the market, its environmental safety should be continually monitored through a formalized system for investigating any reports of wildlife death as a result of pesticides.
Review of non‐target hazards associated with rodenticide use in the USA1
Authors: COLVIN B. A. , HEGDAL P. L. , JACKSON W. B.
Published: April 2008

Relatively few field studies have been conducted to evaluate hazards to wildlife from rodenticide use. In the USA, field studies have been conducted on both acute and chronic compounds, including zinc phosphide, strychnine, 1080 (sodium monofluoroacetate), and the anticoagulants diphacinone and brodifacoum. Techniques employed in these studies have included carcass counts, direct counts, indirect counts, nest site monitoring, radiotelemetry, habitat and diet evaluation, necropsy, and residue analysis. Although zinc phosphide generally is not secondarily hazardous, it can pose primary hazards, especially to seed‐eating and gallinaceous birds and waterfowl. Strychnine can pose primary hazards, such as to seed‐eating birds; secondary poisoning may be minimal unless predators consume stomach or cheek‐pouch contents of poisoned prey. 1080 can result in primary poisoning, but it especially can pose a secondary hazard to mammalian predators; the risk to raptors is minimal. Anticoagulants are toxic both primarily and secondarily; they can pose a substantial hazard to raptors. Gallinaceous birds, however, are quite resistant to them. Hazards associated with any one rodenticide may vary significantly depending upon use pattern (e.g. commensal vs field). Environmental concerns over rodenticide hazards to wildlife are increasing greatly and will affect future registrations.
Relation entre la cinétique et l'efficacité de la bromadiolone chez Rattus norvegicus sauvage1
Authors: NAHAS K.
Published: April 2008

L'efficacité comparée de la bromadiolone et du coumafène contre Rattus norvegicus (souche sensible au coumafène) a étéétudiée en laboratoire avec différentes concentrations en principes actifs et pour différentes durées d'exposition aux appâts. La bromadiolone s'est révélée beaucoup plus active (100% de mortalité en 1 j à 50 ppm) que le coumafène (50% de mortalité en 3 j à 250 ppm). Pour expliquer cette différence d'efficacité, les cinétiques plasmatiques et hépatiques des deux rodenticides ont été comparées chez la même espèce. A une dose équimolaire de 5,69 μmole kg‐1 (correspondant respectivement pour le coumafène et pour la bromadiolone à une seule ingestion d'appâts de 20 et 50 ppm), la bromadiolone a eu une demi‐vie plasmatique de l'ordre de 57,5 h contre 8 pour le coumafène. Le volume de distribution de la bromadiolone était 188 fois plus élevé que celui du coumafène. Le rapport de la concentration hépatique sur la concentration plasmatique a varié en fonction du temps de 14 à 46 pour la bromadiolone et de 0,1 à 0,49 pour le coumafène. Les données cinétiques obtenues montrent que la bromadiolone possède un tropisme et un captage hépatiques importants, qui assurent un blocage prolongé du cycle de la vitamine K et donc une efficacité accrue.
Computers and rodent control research, population monitoring and extension1
Authors: SALMON T. P.
Published: April 2008

Computers, especially microcomputers, are becoming a common tool for researchers, rodent control operators and extension personnel. Gradual but important changes in rodent control are forcing us to review control programmes from both the short‐ and long‐term perspective, including assessing the effects of control on populations over time. In addition, our increased understanding of population dynamics is making population forecasting feasible in a limited number of cases. Computers are becoming an essential component of these activities. From the extension perspective, computers are proving extremely valuable. Information can be stored, searched, updated, and retrieved rapidly, making it readily available to our clientèle. In addition, benefit/cost analyses and management decision scenarios can be demonstrated easily on the computer. This lets growers actively participate in the decision‐making process. The computer is here to stay. We all need to learn its strengths (and weaknesses) and capitalize on them in our rodent control activities.
A detection method for Pseudomonas solanacearum in symptomless potato tubers and some data on its sensitivity and specificity
Authors: JANSE J. D.
Published: April 2008

A detection method is described for latent infections of Pseudomonas solanacearum race 3 in potato. This method is based on extraction of 200 heel ends of potato, followed by screening with an indirect antibody stain (IFAS) and (in IFAS‐positive cases) a pathogenicity test on tomato (PT). Using the method in some sensitivity and specificity tests with more than 600 samples it appears that: (a) its detection level is 104 cells ml‐1 in IFAS and 102— 104 cells ml‐1 in PT; (b) per cent recovery is 0.1–10% (10% at lower contamination levels); (c) false‐positive samples due to cross‐reacting bacteria in IFAS were limited to only 2–3%, using two polyclonal antisera against whole cells of P. solanacearum. The merits of the method in comparison with others (ELISA, selective media) are discussed.
A biotechnological strategy involving monoclonal antibodies for improvement of potato farming by identification and quantification of potato cyst nematodes in soil samples1
Authors: SCHOTS A. , BAKKER J. , GOMMERS F. J. , EGBERTS E.
Published: April 2008

The two closely related nematode species Globodera rostochiensis and G. pallida are one of the major problems encountered in potato cultivation. There is a spectrum of potato plant genes known, which confer resistance to these species and their pathotypes. Potato growing in The Netherlands has to follow strict rules to control spread of the pests. Since distinction between the two nematode species is difficult, a rapid and reliable identification method is needed to allow better use of existing and forthcoming resistant potato cultivars. The aims of this project were: (1) identification and partial purification of species‐specific proteins from the nematodes, (2) production of species‐specific monoclonal antibodies, and (3) development of a screening test for qualitative and quantitative determination of Globodera spp. in soil samples.
Critères de diagnostic des phases d'explosions démographiques et de déclin chez Arvicola terrestris scherman. Exemple de la population du Jura français1
Authors: PASCAL M.
Published: April 2008

Suite à une étude diachronique d'élements de cinétique d'une population locale (Sombacour, Doubs, France) d'Arvicola terrestris scherman, il semblait possible de fonder le diagnostic de la phase de croissance du cycle de pullulation de cette espèce sur le simple examen de l'évolution numérique des effectifs des populations. Afin de vérifier cette hypothèse a l'échelle régionale, un réseau d'observation a été mis sur pied par le Service de la Protection des Végétaux de Franche‐Comté et couvre, depuis octobre 1983, 80 communes du Doubs et du Jura. Il a permis de déclencher une alerte agricole de façon rationnelle et graduellement dans l'espace et le temps, en octobre 1985, avril 1986 et octobre 1987. Une analyse comparative de certains critères morphologiques et de l'intensité du flux de dispersion dans deux situations (la premiere en phase de forte densité du cycle de pullulation, la seconde en phase de déclin) a permis d'échafauder une méthode opérationnelle qui demande confirmation et permettrait le diagnostic fondé de la phase de déclin.
Methods to control the two forms of Arvicola terrestris in orchards in the Federal Republic of Germany1
Authors: PELZ H.‐J. , GEMMEKE H.
Published: April 2008

Different methods had to be developed in the Federal Republic of Germany (FRG) for the control of the fossorial and the aquatic form of Arvicola terrestris. The fossorial form could be controlled on small areas by trapping but, on large areas where this is not feasible, satisfactory results were obtained by fumigation with carbon monoxide or carbon dioxide. The latter was judged superior as it does not endanger man and proved relatively humane. Sound‐emitting devices that were tested against fossorial A. terrestris showed no effect at all. To control the aquatic form, a floating poison‐bait station was developed. It was tested with baits containing bromadiolone, chlorophacinone or calciferol during 2 years on an area of 300 ha. Best results were achieved with fresh carrots soaked with chlorophacinone. Careful checks of the area under investigation did not reveal any evidence of secondary poisoning of non‐target species.
Integrated control of the fossorial form of Arvicola terrestris in orchards1
Authors: JOBSEN J. A.
Published: April 2008

For the replacement of endrin for Arvicola terrestris control in The Netcerlands, an integrated control scheme has been developed. The scheme includes: cultivating arable crops during at least one year before planting of the trees; mole control to prevent easy access of A. terrestris; planting trees in wire netting at the edges of the orchard; early detection of damage, so that spot treatments are still feasible; only when damage is widespread, overall treatment with bromadiolone.
Outbreak of Arvicola terrestris in rice fields in Yugoslavia1
Authors: DUNDJERSKI Z.
Published: April 2008

Macedonia is the southern boundary for the distribution of Arvicola terrestris (water vole) in the Balkan peninsula. Until recently, these voles were found in the region only sporadically, showing none of the cyclic population fluctuations characteristic of microtines in the continental part of Europe. An investigation was started in 1984 when the first visible signs of damage to rice in Kočansko Valley, caused by numbers of voles, were noted. Since then, population numbers have increased, reaching a density of 1000 individuals per ha on one locality. The causes of such an unexpected outbreak and the methods for determining role abundance are discussed. The construction of a dam and the extension of rice cultivation have reduced the natural habitats of both vole predators and their competitors. Increased pesticide and fertilizer usage have also affected the fauna unfavourably. Efficient control was attained by means of zinc phosphide baits, specially before the rice growing season (i. e. in winter and early spring).
Sensibilité de trois espèces de rongeurs commensaux à la brométhaline, en conditions de laboratoire1
Authors: GROLLEAU G.
Published: April 2008

La brométhaline est un produit de synthèse appartenant au groupe des diphénylamines. Ses propriétés rodenticides ont été présentées pour la première fois en 1979 (nom de code = EL 614). Nous avons vérifié, en laboratoire, la sensibilité de Rattus norvegicus, R. rattus et de Mus domesticusà différents appâts contenant 100 ppm de matière active. Deux types d'essais ont été réalisés: sans et avec choix alimentaire. La brométhaline s'est montrée un excellent rodenticide contre M. domesticus, qu'il y ait ou non choix alimentaire. Un tel choix diminue l'efficacité d'environ 10% chez R. norvegicus et R. rattus, ce rodenticide demeurant tout de même très performant. Il ne semble pas y avoir de détection de la matière active dans les appâts, quelle que soit l'espèce de rongeur expérimentée; les consommations journalières réduites, par rapport à ce que nous avons l'habitude d'enregistrer avec les anticoagulants, nous semblent le fait d'une action toxique rapide de brométhaline et non d'une répulsion. Enfin, la brométhaline est efficace contre les R. norvegicus résistants aux anticoagulants, ce qui n'est pas étonnant puisque son mode d'action est totalement différent de celui d'un antivitamine K.
Performance studies with the new anticoagulant rodenticide, flocoumafen, against Mus domesticus and Rattus norvegicus1
Authors: JOHNSON R. A.
Published: April 2008

Flocoumafen is a new, highly potent anticoagulant rodenticide from Shell Research. It is effective against all the economically important species tested to date, including those with warfarin‐resistant strains. This paper is concerned with its performance against two important commensal rodent species, Mus domesticus and Rattus norvegicus. In laboratory studies these two pest species may absorb a lethal dose of flocoumafen by taking a 0.005% (50 ppm) bait as part of their food intake on only one occasion. This single‐feed potency of flocoumafen, combined with its good intrinsic palatability, makes it ideal for use in pulse baiting. Marketed under the Shell trade mark Storm, the principal bait formulation selected for commercialization is the wax‐bound block. Recent advances in formulation development include increased resistance to attack by insects and fungi and the incorporation of a bitter taste which acts as a deterrent for humans without influencing the palatability of the bait to rodents. Flocoumafen's outstanding potency has been confirmed in a wide range of field trials. In the UK alone, almost 70 pen and field trials have been successfully completed with a mean estimated control in excess of 95%.
Control of mole‐rats, Spalax ehrenbergi, with calcium phosphide pellets1
Authors: MORAN S.
Published: April 2008

Control of the mole‐rat, Spalax ehrenbergi, by Polytanol calcium phosphide pellets in field crops and hothouses was evaluated in 11 localities. A dosage of 10–120 g pellets per insert was needed to achieve complete control, in one operation or in 2–3 repetitions. The treatment sites were near mole‐rat mounds or near signs of new damage in the crop. The question of safety in hothouses is discussed.
Diagnosis of viruses in ornamental plants with special reference to serological methods: new developments
Authors: LUISONI E.
Published: April 2008

In support of the work of the EPPO Panel on Certification of Pathogen‐tested Ornamentals, new techniques of diagnosis (since 1980) are presented for viruses of carnation, chrysanthemum, iris, lily, narcissus and pelargonium.
Bacterial pathogens of Gramineae: systematic review and assessment of quarantine status for the EPPO region1
Authors: PAUL V. H. , SMITH I. M.
Published: April 2008

Bacterial pathogens of Gramineae principally belong to the genera Clavibacter, Erwinia, Pseudomonas and Xanthomonas, the last being the most important. A general survey of these pathogens is given, with details on nomenclature, symptoms, natural host range, geographical distribution and potential quarantine significance for the EPPO region. The status of Xanthomonas campestris pathovars with overlapping broad and narrow host ranges on Gramineae is discussed. It is proposed to adopt a broad concept of X. campestris pv. translucens and evaluate it as a potential quarantine hazard for the EPPO region.
Scanning electron microscopy of the establishment of compatible and incompatible Xanthomonas campestris pathovars on the leaf surface of Italian ryegrass and maize1
Authors: DE CLEENE M.
Published: April 2008

Scanning electron‐microscopy observations made on the leaves of Italian ryegrass and maize, inoculated with Xanthomonas campestris pvs graminis, oryzae and oryzicola clearly showed a difference in the distribution pattern among the different pathovars tested. Pvs oryzae and oryzicola could be detected on the leaf trichomes of ryegrass, while pv. graminis was not. On maize leaves, the attachment of pvs oryzae and oryzicola to trichomes was much more pronounced than on ryegrass. In addition, pv. oryzae spread further into leaves of maize than did pvs graminis and oryzicola and could be detected in masses until at least the sixth day after inoculation. These observations suggest that non‐host plants such as maize could function as alternate inoculum sources of pv. oryzae for nearby rice plants.
Epidemiological aspects of bacterial wilt of fodder grasses1
Authors: SCHMIDT D.
Published: April 2008

In order to explain the occurrence of very severe or more moderate wilt of grasses attacked by Xanthomonas campestris pv. graminis, various observations on the factors possibly influencing the epidemics of the disease are summarized in this article. Although natural vectors exist, the main means of transmission is certainly mowing tools. Resistance of the plants can be genetically predetermined or induced by non‐pathogenic phyllosphere bacteria, if these are inoculated at the same time as the pathogen and in sufficient numbers. Young seedlings are particularly susceptible. Strains of X.c. graminis vary in their pathogenicity. Non‐pathogenic strains enhance host resistance. Very severe attacks are related to extremely virulent strains. Crop management can influence the disease which is favoured by various stress situations. Disease spreads extensively when grass is mown under wet conditions. In conclusion, the following measures are recommended to avoid heavy attacks: use of resistant grass cultivars; avoiding contaminated mowing tools, especially for the first cut; cutting under dry conditions.
Research on ‘Xanthomonas translucens’ of wheat and triticale at CIMMYT1
Authors: DUVEILLER E.
Published: April 2008

Bacterial streak caused by ‘Xanthomonas translucens’ is a serious bacterial disease of wheat and triticale and is distributed worldwide. Contaminated seed is the main source of inoculum. As disease incidence appears to be increasing in several countries, research is needed for more resistance in both crops. However, assessment of resistance is hampered by symptom variations and diagnosis can be difficult. Moreover, the nomenclature of the pathogens causing bacterial streak on cereals is rather confusing. A seed detection method has been developed at CIMMYT (Centro Internacional de Mejoramiento de Maiz y Trigo) using a WBC semi‐selective medium. The efficiency of hot cupric acetate has been confirmed to disinfect contaminated seed sets. More research is currently under way on epidemiology to identify the environmental factors favorable for disease expression and to determine the transmission rate of bacteria under Mexican conditions.
Xanthomonas campestris pv. translucens in North and South America and in the Middle East1
Authors: SANDS D. C. , FOURREST E.
Published: April 2008

Bacterial leaf streak and black chaff is a seed‐transmitted disease of cereals caused by Xanthomonas campestris pv. translucens. The bacterium can be identified by its slow growth, slime production, yellow pigment, beta‐galactosidase production, and ice nucleation activity. Aspects of resistance, dissemination, symptoms, and distribution are discussed.
In‐transit shipboard fumigation of pine woodchips to control Bursaphelenchus xylophilus
Authors: LEESCH J. G. , DAVIS R. , SIMONAITIS R. A. , DWINELL L. D.
Published: April 2008

Woodchips from several pine species, infested with the pine wood nematode,Bursaphelenchus xylophilus, were treated in transit using phosphine fumigant. Using aluminum phosphide tablets producing 4 g m−3phosphine, the percentage of infested samples was reduced from 79 to 6% during the voyage from the USA to Sweden. Temperatures in the periphery of the cargo were lower than in the center, and the fumigation was less effective in the periphery. Phosphine concentration had declined to nearly zero before arrival of the chips in Sweden and posed no safety threat to workers or the ship's crew.
An evaluation of the crop‐physiological and epidemiological information in EPIPRE
Authors: DRENTH H. , HOEK J. , DAAMEN R. A. , ROSSING W. A. H. , STOL W. , WIJNANDS F. G.
Published: April 2008

EPIPRE is an integrated pest and disease management system for wheat based on on‐line calculations of costs and benefits of pesticide treatments. It is field‐specific and utilizes disease and pest incidences which are collected by the participating farmers. Incidences are transformed to severities through pest‐specific relations with which a prediction of the epidemic is made according to an exponential development model. Integration of the epidemic over time, with multiplication by a pest‐specific damage factor, delivers the expected damage till the end of the season, expressed as a fraction of the expected yield. Chemical control is only recommended when benefit of control exceeds total costs, including those for pesticide(s), labour, machinery and wheel‐track damage. The current model needs improvement especially for the forecast of septoria blotch diseases, the field‐specific quantification of the relative growth rates used and the damage relations of Puccinia striiformis and Mycosphaerella graminicola/Leptosphaeria nodorum. Also the cost‐benefit analysis of the model can be improved, and it therefore, in the near future, needs contributions from research topics such as phytopathology, crop physiology, farm economics and information management. Using the model during the last 10 years has led to a reduced input of pesticides, which in its turn results in a lowering of production costs and a marked decrease in environmental pollution. Therefore future efforts to improve the model seem to be worthwhile.
Echanges intercontinentaux de peupliers destinés àľamélioration: point de vue ďun pathologiste européen
Authors: PINON J.
Published: April 2008

Une liste de champignons présumés pathogénes pour le peuplier, et qui n'ont pas encore été détectés en Europe, a été dressée. En dépit des erreurs et omissions toujours possibles, cette liste met en lumière les risques potentiels ďintroduction de parasites. II est suggéréďimporter les peupliers de préférence àľétat de semences ou de cultures in vitro lorsqu'on désire du matériel cloné. Si néanmoins des boutures sont introduites, elles devraient être placées en serre de quarantaine et seules les pousses apparemment saines qui en résultent seraient retenues pour la multiplication par bouturage herbacé alors que la bouture originale serait détruite. Les plants issus de semis ou de bouturage devraient être installés ensuite dans une pépinière prévue pour cet usage, située hors des régions populicoles et soumise àľinspection phytosanitaire. II est nécessaire ďengager une coopération internationale pour aboutir à une définition commune des races de rouille et des clones qui pourraient servir de plantes‐pièges.
A new virus disease of watercress in England1
Authors: WALSH J. A. , CLAY C. M. , MILLER A.
Published: April 2008

In 1983 plants showing symptoms typical of watercress chlorotic leafspot agent (WCLSA) were found in Kent (GB). Later, plants showing similar symptoms were found in Dorset (1986) and Hampshire (1987), the main watercress‐producing regions of England. These plants, unlike those infected with WCLSA, contained virus particles which were isometric with diameters of 37‐38 nm. An antiserum to the virus was produced, with a titre in immunodiffusion tests of 1/128 and this gave good results in immunosorbent electron microscopy (ISEM) and ELISA tests on crude plant sap. Purified preparations of the virus reacted positively in ISEM and immunodiffusion tests with an antiserum to watercress yellow spot virus, a partially described virus occurring in France. Tests suggest that the crook root fungus Spongospora subterranea f.sp. nasturtii is probably the vector of this virus but other means of transmission cannot be excluded. Virus incidence within watercress beds varied, with little or no infection in the water inlet region of the bed where there are also low levels of crook root infection, higher levels in the central region and highest levels at the outlet region where crook root infection is also highest.
Tobacco stunt and lettuce big‐vein viruses: biology, economic impact and control1
Authors: HIRUKI C.
Published: April 2008

Two soil‐borne virus diseases, tobacco stunt and lettuce big‐vein, have many unique features in common, such as highly sensitive temperature dependency for disease development, in vivo acquisition of virus by the fungus vector Olpidium brassicae, long‐term persistence of virus in the fungal resting spores, extreme instability of virus in vitro, dsRNA and coat protein unique for rod‐shaped viruses, and others. Recent changes in agricultural practices have increased the incidence of these old diseases, in particular lettuce big‐vein, causing serious damage to industry. Frequent incidence of the latter has been reported from intensively managed glasshouses and from the use of soil‐free environments, where plants were grown with circulating liquid nutrients on certain support matrices. Chemical control of O. brassicae, particularly at the zoospore stage, appears feasible by continuous application of certain fungicides and/or non‐ionic liquid surfactants that are effective in killing virus‐transmitting zoospores. In the long term, breeding of cultivars resistant to the fungus or to both the fungus and virus, and biological control of the vector with other rhizosphere‐inhabiting microorganisms may be possible.
Optimizing sampling strategies for nematode‐transmitted viruses and their vectors1
Authors: BOAG B. , BROWN D. J. F. , BANCK A. S. G.
Published: April 2008

The detection of virus‐vector nematodes and the viruses they transmit depends upon the efficiency of the sampling and extraction procedures. A knowledge of the horizontal and vertical distribution and population dynamics of the vectors is required to maximize the chances of detecting small numbers of nematodes, while data on the size of virus patches are needed for quantifying the probability of finding the virus in the field. Information on the spatial and temporal distribution of both vectors and viruses is reviewed and, in light of the limited present knowledge, optimum sampling strategies are recommended.
Influence of RNA composition of beet necrotic yellow vein furovirus isolates and of the sugarbeet cultivar on the translocation of the virus in mechanically inoculated sugarbeet roots1
Authors: KOENIG R. , EHLERS U.
Published: April 2008

The roots of young sugarbeet seedlings (5‐12 days old) were inoculated mechanically with beet necrotic yellow vein furovirus (BNYVV). Vortexing of the seedlings in virus‐containing suspensions proved to be especially effective. Higher percentages of infected tap roots were observed with a highly susceptible than with a tolerant cultivar. In the susceptible cultivar, the virus spread more readily from the tap root to the newly formed lateral roots than in the tolerant cultivar, indicating that the latter had a partial resistance to the virus. The translocation of the virus also depended on its RNA composition. An isolate with intact RNA3 and RNA4 was much more efficiently translocated to the lateral roots than an isolate which lacked these two RNAs. So far we have been unable to infect hairy roots of sugarbeet with BNYVV. These hairy roots had been induced by infection with Agrobacterium rhizogenes and were propagated in liquid culture.