bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Forecasting in Crop Protection Decision Making: an Economic Viewpoint1
Authors: NORTON G.A.
Published: April 2008

In making crop protection decisions, farmers have to answer two questions: what type of control measure(s) should I adopt? How should I apply this (these) measure (s), when, how frequently, etc.? The answer to these questions will depend upon: a) the dimensions of pest attack and the damage it causes, b) farmers' goals, c) the range of protection measures available to them which they can use, and d) the information available, in the form of monitored and forecast information. It is within this context that the role of forecasting is considered. An analysis is made of the possible impact that forecast infomation can have on farmer decision‐making, particularly with regard to the accuracy of the forecast and the time at which it is available. This leads on to the problem of assessing the value of a forecast at a regional level, against which the costs of providing such information can be set. Finally, situations in which forecast information is likely to be of greatest value (and of least value) are identified, and implications are drawn concerning the institutional and other changes that could be taken to allow better use to be made of forecast information.

Lorsque les agriculteurs decident de proteger leurs cultures, ils doivent repondre aux deux questions suivantes: quel est le mode d'intervention a choisir et comment, quand et a frequence faut‐il intervenir. La reponse dependra notamment: de I'etendue de I'infestation et de L'importance des deglts; des buts que s'est assignes L'arboriculteur; de la gamme de methodes dont il dispose; des previsions qui lui sont fournies. La prevision est condideree dans ce cadre, puisqu'elle est susceptible d'infuler sur les decisions de L'agriculteur dans la mesure ou elle est etablie avec precision et au bon moment. I1 est donc utile d'evaluer L'inter6t economique d'une prevision regionale en faisant intervenir le cofit de celle‐ci. Enfin, il est fait etat de situations dans lesquelles la prevision est profitable ou non. Suivant les cas, certaines modifications structurelles peuvent s'imposer afin de mieux tirer benefice des previsions.
The Breeding and Use of Varieties Resistant to Heterodera avenae1
Authors: ANDERSEN Sigurd
Published: April 2008

An international test collection has been used widely to determine the races of Heterodera avenae. Many different races are found. At least three sources of resistance depend on a single dominant gene, and tranfer of resistance to commercial varieties has not given any trouble in Denmark. Twelve high‐yielding and resistant varieties are available to the farmer. The resistance gene Ha2 is linked to the marker gene pau, thus selection for this gene will be a selection for resistance too.

RESUME

Sélection et utilisation de variétés résistantes à Heterodera avenae

Une importante collection internationale de cultivars a servi à l'identification des races d'Heterodera avenae dont le nombre est important. Il existe au moins trois sources de résistance qui dépendent d'un seul gène dominant et la transmission de la résistance aux variétés commerciales ne péesente pas de difficultéQs au Danemark. Douze variétés résistantes de haut rendement sont disponibles pour les agriculteurs. Le gène de résistance Ha2 est directement relié au gène indicateur pau, si bien qu'une sélection de ce gène entraînera ipso facto une sélection pour la résistance.
Methodology for the Breeding of Forage Plants for Resistance to Fungal Diseases1
Authors: GONDRAN J.
Published: April 2008

In order to breed disease‐resistant fodder plants, it is necessary to improve our knowledge of the yield losses due to diseases, to develop better methods for screening disease resistance, and to test for the stability of the resistance obtained. The tests need to be compared in different European countries.

RESUME

Methodologie pour la sélection de plantes fourragéres résistantes aux maladies fongiques

Dans la sélection de plantes fourragères résistantes aux maladies il est nécessaire d'améliorer nos connaissances sur les pertes de récolte causées par les maladies, de mettre au point de meilleures méthodes permettant de trier les plantes résistantes et de vérifier la stabilityé de la résistance des variétés ainsi obtenues. Une véritable comparaison d'essais de ce genre ne peut se faire que lorsque ceux‐ci sont installes dans les différents pays dcar;Europe.
Resistance to Bacterial Wilt (Xanthomonas graminis) Increases Yield and Persistency of Lolium multiflorum1
Authors: SCHMIDT D. , NUESCH B.
Published: April 2008

Xanthomonas graminis is the causal agent of a vascular wilt disease of forage grasses. A good correlation was established between the yield decrease of perennial ryegrass cultivars during hot, dry summers, and their susceptibility to bacterial wilt as determined in inoculation tests in the greenhouse and by field observations. When compared with the productivity of the most resistant varieties, 40 % yield loss may be observed for the later cuts of very susceptible cultivars. This corresponds to about 20 % loss over the whole year. The Westerwold ryegrasses are very sensitive. This feature might be in relation to their alternativity. The Swiss cultivars of Italian ryegrass Turilo, Lipo and the semi‐alternative variety Defo are among the most resistant ones. They have been bred under a high natural infection pressure at Ziirich‐Reckenholz. Little is known about the genetics of this resistance. Screening in the susceptible Westerwold cultivars Tewera and Woldi during two generations has slightly increased their resistance. Artificial inoculations are now used in greenhouse screening, in order to accelerate breeding for resistance.

RESUME

La résistance au flétrissement bactérien causé par Xanthomonas graminis augmente le rendement et la persistance de Lolium multiflorum

Xanthomonas graminis cause une trachéobactériose des graminées fourragères qui peut entrainer un fletrissement rapide. Pendant les étés chauds et sees, on a observé en plein champ une relation entre le dépérissement de certaines variétés de Lolium multiflorum et leur sensibilité au flétrissement bactérien. En serre, des infections artificielles ont confirmé cette relation. Pour les variétés les plus sensibles, les pertes de rendement enregistrées en arrière‐saison peuvent etre jusqu'à 40 % superiéures à celles des variétés les plus résistantes, ce qui correspond à une perte de 20 % sur l'ensemble de l'année. Les ray‐grass Westerwold sont particuliérement sensibles, ce qui pourrait être en relation avec leurs propriétés d'alternance. Les variété s suisses de ray‐grass d'ltalie Turilo, Lipo et même la variété semi‐alternante Defo sont parmi les plus résistantes; elles ont été sélectionnées à Zürich‐Reckenholz sous une forte pression naturelle du parasite. Le mécanisme génétique de cette résistance est encore mal connu. Deux cycles de sélection réalisés pour les variétés de ray‐grass Westerwold Tewera et Woldi n'ont que légérement améliore leur résistance. Actuellement, les infections se font en serre, ce qui permet d'accélerer la sélection pour la résistance des ray‐grass d'ltalie.
Pathogen Response to Host Resistance and its Implication in Breeding Programmes1
Authors: BARRETT J.A. , WOLFE M.S.
Published: April 2008

During the last six years a series of theoretical and experimental studies have been made of possible strategies of variety use. Most of this work has concentrated on an assessment of the use of variety mixtures for disease control. Over the last four years extensive field trials using barley variety mixtures have been carried out. In these trials the evolution of powdery mildew has been followed. Assessments have been made of the relative frequencies of powdery mildew genotypes carrying one, two or three virulence factors. The results of this monitoring programme have been compared with the predictions of a mathematical model of pathogen evolution. From this combined approach we have been able to build up a fairly comprehensive picture of pathogen evolution. The results of this work will be discussed with emphasis on selection of varieties for disease control.

RESUME

Comportement des populations d'agents pathogènes face à la résistance de la plante‐höte et conséquences pour les programmes de sélection

Depuis plusieurs années la stratégie de la sélection qui consiste à faire appel à des variétés differentes fait l'objet d' études théoriques et expérimentales. Celles‐ci portent essentiellement sur l'evaluation de l'intérét que présentent les mélanges de variétés pour assurer la protection contre les maladies. Des essais de plein champ, réalisés sur de vastes surfaces et comprenant des mélanges de variétés d'orge, sont en cours depuis quatre ans; ils ont permis de suivre l' évolution des populations d'Erysiphe graminis f. sp. hordei et de proceder à l'analyse de la fréquence sélective des génotypes du champignon munis d'un, de deux ou de trois facteurs de virulence. Les résultats de cette étude sont ensuite comparés aux prévisions obtenues par un modéle mathématique établi en fonction de l'evolution de l'agent pathogéne. En comparant les deux méthodes il est possible de dresser un tableau exact de l' évolution du parasite. Les conclusions qu'il faut en tirer pour la sélection de variétés résistantes sont discutées.
Searching for Host‐Plant Resistance to Arthropods in Agriculture1
Authors: HARRIS M.K.
Published: April 2008

Host‐plant resistance to arthropods for use in agriculture is proposed to‐ have arisen through 1) coevolution due to natural selection pressure by the arthropod, 2) coevolution without natural selection pressure by the arthropod and 3) isolation of the plant and arthropod. Arguments are developed indicating that the latter situation results in germplasm sources which show the most promise for obtaining suitable numbers of genes for arthropod resistance in agriculture.

RESUME

Recherche de la résistance contre les arthropodes nuisibles aux cultures

La résistance des plantes aux arthropodes peut jouer un rǒ1e important dans la protection des plantes; il est admis qu'elle trouve ses origines, soit dans une évolution paralléle avec pression de sélection de la part de l'arthropode, soit dans une évolution paralléle mais sans cette pression de sélection, soit dans une évolution séparée de la plante et de l'arthropode, isolés l'un de l'autre. Le materiel génétique provenant de ce dernier type d'évolution apparait comme le plus prometteur pour la découverte d'un nombre suffisant de génes de résistance qui pourraient ětre utilisés sur le plan pratique.
Nematode Inoculum Propagated in Monoxenic Plant Tissue Cultures ‐Nematode Bank1
Authors: ERIKSSON K.B.
Published: April 2008

Plant breeders and nematologists in Scandinavia have cooperated in the development of « a nematode bank » in an attempt to solve the problem of inoculum supply in breeding for nematode resistance. Stem nematodes, Ditylenchus dipsaci, were effectively propagated in monoxenic plant callus tissue cultures, where the nematodes seemed to thrive and reproduce irrespective of the origin of the callus. Host specificity characters appeared to be only partly retained in the callus tissue. Callus from resistant and susceptible cultivars of the same plant species supported about the same numbers of nematodes. Several stem‐nematode races and populations from various countries are propagated in the bank; some having now been maintained continuously for more than 15 years with no apparent changes in nematode aggressivity and host specificity. Other nematodes maintained in the bank are Ditylenchus destructor, Aphelenchoides fragariae, Pratylenchus spp., and attempts are being made to include Globodera and Heterodera spp. The greatest consumers of nematodes from the bank are plant breeders in Sweden and Denmark, but nematodes are also delivered to other countries and to research workers.

RESUME

La banque de nématodes en culture de tissu végétal monoxénique

Les sélectionneurs et nématologues scandinaves ont coopéré afin de créer une « banque de nématodes » qui permettra de résoudre les problémes d'approvisionnement en inoculum nécessaire à la sélection de plantes résistantes aux nématodes. Les populations du nématode des tiges (Ditvlenchys digsaci) se développent facilement dans les cultures de cals monoxéniques et s'y multiplient aisément, quelle que soit l'origine du cal. Les caractéres spécifiques de la plante‐hôte semblent ètre largement perdus dans une culture de cal. I1 apparait en effet que les cals provenant de plantes résistantes ou sensibles permettent de multiplier indifferemment les nématodes. La banque de nématodes comprend actuellement plusieurs races de D. dipsaci provenant de pays différents. Certaines d'entre elles ont été maintenues en culture artificielle au cours de 15 ans sans que ne paraisse la moindre indication d'une modification de l'agressivite des nématodes ou de la spécificité envers la plante‐hôte. Les banques contiennent également les espéces Dit.vlenchus desirucior et Aphelenchoides fragariae, ainsi que Pratylenchus spp. Globodera et Heteroderu spp. Font actuellement l'objet de tentatives de culture artificielle. La banque approvisionne avant tout les sélectionneurs danois et suédois, mais les nématodes sont également expédiés aux chercheurs d'autres pays.
Standard Methods for the Assessment of Sunn Pests of Wheat and for Crop Losses caused by them
Authors: WALKER P.T.
Published: April 2008

In an attempt to standardize methods of assessment of Eurygaster spp. and Aelia spp., some methods published in USSR, Romania and Turkey are reviewed and details given. These are: 1) counting overwintering adults in quadrats or along a line; 2) counting old adults in quadrats or by sweep net after migration; 3) counting nymphs in quadrats. Methods of assessing crop loss caused are: 1) counting attacked stems of young wheat; 2) counting attacked ears; 3) identification and counting of attacked grain at harvest; 4) caging different numbers of nymphs and adults, and taking yields, grain weight, germination etc.; 5) assessing the effect on baking quality of flour etc. The effects of different numbers of insects per m2 on yield are given. It is suggested that standardization of such methods would lead to improved cooperative studies between different countries.
Fluctuations in Sunn‐pest Populations in South‐eastern Anatolia
Authors: ADIGÜZEL N.
Published: April 2008

Sunn pest (Eurygaster integriceps) is the most serious and widespread pest of cereals in south‐eastern Turkey. It is very important to estimate its spring populations, and the area possibly needing to be treated, a few months before they migrate to the fields. The field populations of the pest and the severity of epidemics can be forecast from the population density of overwintering adults per plant in the overwintering localities. To do this, surveys have been made since 1955 on 25 selected mountain sites. Parallel to these investigations, the population of overwintered adults per m2 in cereal fields has been determined in order to fix the area to be treated, since 1956. A relation can be seen between the population density of overwintered adults per plant and the next season's populations in the infested areas.
Research on Septoria Leaf Blotch: Recent Advances1
Authors: EYAL Z.
Published: April 2008

A review of the recent advances in research on Septoria leaf blotch is given with particular emphasis on epidemiology and control strategies. The effect of straw infected with pycnidia of Septoria tritici or perithecia of its perfect stage Mycosphaerella graminicola, infected seeds and alternative hosts on the initiation of epidemics is discussed. Reference is made to the effect of plant stature on the vertical progress of the disease. The role of fungicide protection in the control of the disease is discussed. Resistance and tolerance to Septoria leaf blotch is dealt with in more detail, with reference to the author's own research, and with implications on breeding strategies.
Prevalence and Control of Septoria Leaf Blotch in the Aegean Region1
Authors: SAYDAM C.
Published: April 2008

While a number of common wheat diseases are well controlled in Turkey, Septoria leaf blotch (due to Septoria tritici) has been gaining in importance in Turkey since 1967, when the Mexican wheat varieties were first imported. Surveys in six locations in the Aegean Region in April‐May 1975–1977 showed that S. tritici was common throughout the region. In 1978, trials with four fungicides (mancozeb, benomyl, carbendazim in two formulations) in eight combinations showed that threefold treatment with benomyl was most effective. However, a better economic return was obtained with two applications of Derosan. The first application can usefully be combined with normal weed control.
New Trends in the Chemical Control of Wheat Diseases1
Authors: FEHRMANN H.
Published: April 2008

Following a list of the economically most important fungal wheat diseases, recent trends in chemical seed treatment are discussed. Different fungicide mixtures are now available for the replacement of mercurial dressings, but are generally more expensive. The control of fungal diseases by spraying has become more and more common over the past ten years in certain countries. Advantage has been taken of the curative action of the modern systemic chemicals. The major diseases are powdery mildew, rusts, eyespot, glume‐and leaf‐blotch. The general application of a fungicide programme is restricted by regional wheat prices, and should also be limited to reduce environmental contamination. Knowledge about economic thresholds and correct timing of control are indispensable, and in special cases the development of warning systems is advisable. The role of Cycocel (chlormequat) is also discussed. A danger of fungicide resistance in populations of plant pathogenic fungi has arisen with the introduction of the systemic fungicides (one‐site‐inhibitors). As yet, however, no economically important case of fungicide resistance within cereal pathogens is known. Factors favouring the stepwise selection of resistant strains under field conditions are discussed in detail, and experimental data are presented on this subject. Other positive or negative side‐effects of the modern fungicides are described.
Concept and Practice of an Economic Threshold for Erysiphe graminis F. sp. tritici1
Authors: PARMENTIER G.
Published: April 2008

An assessment method for Erysiphe graminis f. sp. tritici is proposed to help farmers predict potential losses superior to the cost of chemical control. On the basis of numerous and varied trials since 1950, the economic threshold of winter wheat powdery mildew appears to be around 25 pustules present on the two faces of the blade of the three upper leaves of 20 ear‐bearing tillers at the flowering stage. In order to avoid overstepping this economic threshold, nitrogenous fertilizer must be provided in a fractional manner on the basis of soil analysis, especially in the root layer. This is particularly important just after the winter. Varieties overstepping the threshold under these conditions should be avoided, or else treated with fungicide.
Seed‐borne Pathogens on Wheat (Particularly Smuts) in Turkey1
Authors: PARLAK Y.
Published: April 2008

The important seed‐borne diseases of wheat in Turkey are common bunt (Tilletia caries and T. foetida), loose smut (Ustilago nuda tritici), dwarf bunt (T. contraversa) and flag smut (Urocystis tritici). Seed treatment against common bunt is widely used in Turkey. The damage is about 10–15 %, sometimes 90 % in some fields where seeds are sown without treatment. About 10 % of wheat fields were infected with bunt during 1972–1974. Seed treatment with carboxin (Vitavax) is recommended against loose smut of wheat in Turkey, but has not yet been used. Some wheat varieties, especially Siirak (1593/51) wheat, are highly susceptible to loose smut. The proportion of smut‐infected heads reached 30–40 % in this variety and about 32 % of wheat fields were infected with loose smut during 1972–1974. The damage was about 6 % in infected fields. Yield losses were at least 35,000 tons. Dwarf bunt is distributed at high altitude (1300–2000 m) in eastern Turkey; 2500 ha of wheat fields are infected with dwarf bunt. The disease causes 1–80 % losses in some fields. The wheat variety Yayla 305 is recommended for infected areas. Flag smut is present in some areas of Turkey, but yield losses are not important. Seed treatment is effective against seed‐borne spores.
Maize Pests and their Importance in Turkey1
Authors: LODOS N.
Published: April 2008

Maize and related crops suffer from a large number of insect pests in Turkey but all are not of the same importance in different parts of the country. This paper lists about 80 species, of which only a few (Sesamia nonagrioides, Helicoverpa armigera, Ostrinia nubilalis, cutworms (Agrotis spp.), Tanymecus dilaticollis, Gryllotalpa gryllotalpa) are of primary importance. The pest status and distribution of each species is described.
Lutte biologique contre Ostrinia nubilalisà l'aide des trichogrammes1
Authors: VOEGELÉ J.
Published: April 2008

La technique de lutte contre la pyrale du maïs à l'aide des trichogrammes, déjà répandue depuis longtemps en URSS, a été récemment introduite et adaptée en Europe. Un certain nombre de paramètres sont à examiner pour rendre la méthode fiable dans des conditions de hauts potentiels de production. II y a lieu de bien choisir tout d'abord l'espèce la mieux adaptée aux conditions climatiques du lieu, des différences importantes de résistance pouvant exister entre l'une ou l'autre de ces espèces vis‐à‐vis des humidités et températures extrêmes. Ces espèces étant souvent jumelles, il est nécessaire de disposer de techniques de distinction très élaborées. La production de masse de ces oophages est possible à partir d'un grand nombre d'hôtes et même d'œufs artificiels, mais la valeur alimentaire de ceux‐ci interfère directement sur le potentiel biotique des parasites. La nécessité de prévoir une production qui soit compétitive avec les insecticides chimiques au niveau du prix de revient requiert une orientation vers des unités de production automatisées à haut rendement. Une diapause de très longue durée autorise un conditionnement relativement facile de ces auxiliaires et facilite leur distribution (mécanique ou manuelle) dans les parcelles. Un contrôle de la qualityé est à assurer à tous les niveaux de la production et de l'utilisation des trichogrammes, meme au niveau génétique.
Noctuid Species Causing Damage to Maize in Turkey1
Authors: OZDEMIR N. , UZUNALI S.
Published: April 2008

In Turkey, maize is grown in the Black Sea, Marmara and Aegean Regions as well as in the southern part of the country, with a total area of 600,000 ha. Control measures againsts pests play an important part in maize production. Noctuid species are important maize pests in Turkey, and the following species occur: Scotia ipsilon, Scotia segetum, Sesamia nonagrioides, Sesamia cretica, Mythimna loreyi, Mythimna unipuncta, Spodoptera exigua. Research on the ecology of S. ipsilon is being conducted in the Black Sea Region. This species passes through 4 to 5 generations annually. In recent years, S. nonagrioides has been found in the Aegean Region and studies on this pest have started. S. cretica is widely distributed in the Marmara, Mediterranean and South‐eastern Regions of Turkey. This species produces two generations annually. M. loreyi and M. unipuncta cause damage only in limited areas. Helicoverpa armigera and S. exigua are widely distributed throughout the maize‐growing regions, but cause considerable damage only in limited areas.
Etude du développement de Sesamia nonagrioides et établissement de modèles pour la prévision de ses populations dans la nature1
Authors: HILAL A.
Published: April 2008

Dans cette étude, nous avons essayé de préciser l'effet des températures constantes et variables sur le développement de Sesamia nonagrioides. Les seuils thermiques inferieurs pour le développement normal de cet insecte ont également été déterminés. La connaissance de ces seuils pour les différents stades de la sésamie a permis le calcul de la somme des températures en degrés‐jours nécessaires pour son développement. Ces calculs ont été effectués selon la loi de la constante thermique: K = Y (T ‐ C). Cette somme est de l'ordre de 590 dj elle varie légèrement en présence de températures ambiantes basses ou élevées. La connaissance des dates de sortie des adultes (pièges lumineux) et des sommes thermiques nécessaires au développement des différents stades de la sésamie permet à tout moment de suivre 1'évolution des populations de cet insecte dans la nature.
Mycological Diagnostic Problems1
Authors: BOEREMA G.H. , KESTEREN H.A. VAN
Published: April 2008

In diagnostics we are constantly confronted with the gaps that exist in our knowledge of the pathogenic fungal flora. This situation is illustrated by recent information concerning various economically important fungal diseases. Where such problems arise it is only through international cooperation in diagnostic mycology that they can be efficiently tackled and solved. It appears that with increasing frequency the exact identification and differentiation of fungi is only made possible through familiarity with their growth characteristics in culture. Fungus culture collections can here play an important role, since exact comparison and identification is made possible. Such pathogenic fungi should be made available for diagnostic purposes under the auspices of the Plant Protection Services, so that the risk of unwanted spreading of these pathogens can be avoided. The Plant Protection Services would in fact become more effective in their attempts to prevent and limit the distribution of harmful organisms.
Biological Control of Plant Pathogens: Present Status and Perspectives in Italy
Authors: BAZZI C.
Published: April 2008

Interest in the biological control of plant pathogens has been increasing in Italy in the last few years. Current or completed research programmes at some University and/or CNR (National Research Council) Institutions concern the following topics: a) biological control of crown gall with Agrobacterium radlobacter strain 84; b) biocontrol of some forestry diseases caused by fungi; c) integrated biological control of grey mould on grapevine; d) biocontrol of Fusarium dry rot on maize and sorghum and of Rhizoctonia rot on eggplant and tomato with Trichoderma viride; e) seed and root≪ bacterization ≫ as a means of biological control of some fungal diseases of horticultural plants; f)≪ suppressive ≫ effect of some Italian soils to Fusarium oxysporum f.sp. dianthi: g) biologically induced resistance against bacterial, fungal and viral diseases. In this contribution, the results obtained are reported, together with comments on the prospects for practical application of each type of biological control. Evaluation of the reduction in the use of pesticides against the same pathogens is not currently possible, owing to lack of data (except for programmes b) and c) above). Biological control will only become a common and widespread agricultural practice if a number of conditions are satisfied, including the establishment of registration guidelines for microbial and viral pesticides. The criteria for the evaluation of biological control organisms in the agricultural environment must be revised and the technical‐legislative problems must be solved. A Commission in the European Community is currently examining the question.
San José Scale in Deciduous Fruit Orchards of Some European Countries (Survey of Scale Insect Infestations in European Orchards No. IV)
Authors: KOZAR F. , KONSTANTINOVA G.M.
Published: April 2008

Fruit tree branch and bark samples have been collected from several European countries (Czechoslovakia, Greece, Hungary, Poland, Turkey, European part of USSR) from apple, pear, peach, plum, cherry and sour cherry. Twenty‐five scale insect species were found in the samples. Distribution maps of Quadra & pidiotus perniciosus on different fruit species are given. No significant changes in the distribution of this species in Central Europe can be observed in the last 30 years. Q. perniciosus is present in higher density on apple wherever it occurs, and is less frequent on pears and plums. It is frequent on peach and sometimes on cherry, but generally at low densities. It is rare on sour cherry.
Implementation of the EEC Frontier Directive1
Authors: OBST D.
Published: April 2008

By Council Directive 77/93/EEC, the EEC has set up a uniform EEC plant quarantine system which aims to have standardized EEC requirements, to protect the Community as a whole against the introduction of exotic harmful organisms, and to facilitate trade between Member States of EEC. The system covers intra‐community trade in plants and plant products as well as their imports from outside the Community. Member States are bound by this system. With one exception, all Member States have now implemented it. The necessary details of its interpretation will be decided at Community level and not unilaterally. EEC operates the system through close cooperation between the plant protection organizations of the Member States and the Commission. Special actions in respect of some exotic diseases have already been taken or are in preparation. EEC is interested in the experience of EPPO or other international organizations and is anxious to contribute to EPPO activities to protect the EPPO region from the introduction of exotic harmful organisms.
Pests and Pathogens Intercepted in the Past by the Danish Plant Protection Service1
Authors: ANDERSEN H.
Published: April 2008

The author reviews the principal pests and pathogens intercepted on imported plants and plant products in Denmark and considers the measures required to reduce risks in future.
Ways of Preventing the Introduction of Pests and Pathogens in the Future by Compulsory Plant Health Control1
Authors: JACOBSEN P.
Published: April 2008

The Danish plant quarantine regulations are reviewed, together with the plant health controls on exported plant material. All material for sale and planting, whether in Denmark or for export, is now subject to phytosanitary inspection.
European Forestry and Ceratocystis Species1
Authors: GIBBS J.N.
Published: April 2008

Ceratocystis spp. are responsible for some serious tree diseases. Vascular mycosis of oak, oak wilt, Dutch elm disease, and canker stain of plane are discussed in the context of the information required by a plant protection organisation concerned with the risks created by specific pathogens.
Le feu bactérien: problèmes posés par son extension dans l'Europe méridionale1
Authors: RIDÉ M.
Published: April 2008

L'explosion récente du feu bactérien dans les vergers de pomoidées du sud‐ouest de la France crée pour ce pays et les contrées productrices de la zone méditerranéenne une situation très vulnerable. Le rôle des facteurs qui ont favorise cette extension est discuté: conditions climatiques (température élevée et fréquence des précipitations), structure variétale des vergers (dominance de cultivars sensibles et très sensibles), étalement des secondes floraisons jusqu'à l'automne, activité intense des insectes et des oiseaux. La nécessité d'une intensification des recherches adaptées aux systèmes de production de l'Europe méridionale est justifyée. Les recherches sont à l'heure actuelle orientées vers une méilleure connaissance des sources d'inoculum et de l'épidémiologie d'Erwinia amylovora dans les conditions du verger français, l'établissement de schémas de prevision des risques de développement de la maladie utilisables par l'ensemble des pays concernés et, avec leur concours, l'étude de la variabilityé de la bactérie qui conditionne l'orientation des programmes de sélection pour la résistance du poirier et du pommier. Les programmes mis en place sont complémentaires de ceux des Etats‐Unis et de l'Europe du Nord, en demeurant tournés vers l'économie de la zone méditerranéenne.
Colorado Beetle ‐ Recent Work in Preventing its Establishment in Britain1
Authors: AITKENHEAD P.
Published: April 2008

Current measures for excluding the Colorado beetle from Britain and for intercepting it are reviewed. Publicity is used to obtain a high rate of interceptions on non‐host commodities by the public; at‐entry inspection of imported commodities is considered less effective. Eradication procedures are described using recent incidents in field crops of potatoes and rye as examples. Application of available data to published biological criteria indicates that Colorado beetle could survive and damage crops in Britain. A simple cost/benefit analysis is also attempted in order to compare living with the pest with excluding it. At present exclusion seems the less costly option. Noting geographical variations recently discovered in Colorado beetle, the author proposes that the EPPO region should continue to exclude this pest from America.
Chrysanthemum White Rust1
Authors: WATER J.K.
Published: April 2008

Since its introduction from South‐east Asia into several western European countries, chrysanthemum white rust (Puccinia horiana) has become a serious problem for chrysanthemum growers. This rust is easily spread, by spores and infected plant material, and chemical control is laborious. Some EPPO countries are still able to prevent its establishment. Other EPPO countries, with a ← settled → white rust condition, have developed an inspection system which enables them to keep the disease at a low level. The approach in both situations is discussed.
The Risks from Exotic Potato Viruses1
Authors: HOWELL P.J.
Published: April 2008

Potato viruses not known in Europe are listed and discussed in the context of risks they present to potato growing in western Europe. Aspects of mode of entry via true seed, tissue culture, rooted cuttings or tubers are assessed and the latest position is outlined in relation to developments within EPPO and the EEC. A suggested approach to post‐entry quarantine testing for such material is given.
Action des fongicides sur Erynia neoaphidis, un entomopathogene1
Authors: DELORME R. , FRITZ R.
Published: April 2008

L'activité préventive, curative et inhibitrice de sporulation de 19 fongicides est testée en laboratoire sur Erynia neoaphidis, pathogène d'Aphis fabae. Afin d'obtenir des taux de contamination et de mortalitéélevés, les conidies sont produites directement à partir de pucerons infectés. L'activité préventive des fongicides dépend tout d'abord de la periode qui sépare le traitement et la contamination. Aucun des fongicides testés n'a une action curative; il semble que la pénétration mycelienne soit trop rapide pour que les fongicides puissent agir. Seuls les produits non systémiques s'averént actifs, aux doses recommandees, contre le développement d'E. neoaphidis sur A. fabae. Les dithiocarbamates, le soufre et le ditalimphos ont le plus grand effet. Bien que ces tests de laboratoire permettent d'apprécier les toxicités relatives des fongicides dans des conditions déterminees, ils ne donnent apparemment qu'une indication très insuffisante des effets réels sur les maladies épizootiques en plein champ.
Effect of Fungicides on Septoria nodorum and Wheat Green Leaf Area1
Authors: JORDAN V.W.L.
Published: April 2008

Fungicides applied at different growth stages were compared for the control of wheat glume blotch, caused by Septoria nodorum (Berk.) Berk. In glasshouse and small‐scale field tests, 11 commercially used fungicides, when applied to fully emerged wheat ears, cv. Hobbit, gave only partial control of ear infection by spores applied immediately after spraying. They gave better control of infection of leaves by a similar inoculum. Larger field trials, moreover, indicated better foliar and ear disease control from fungicide applications made before ear emergence, compared with those applied later.

In another field trial, nine fungicides were applied to replicated plots of winter wheat, cultivars Atou and Hobbit at GS 31, GS 39, GS 55 or GS 71. On five occasions from anthesis (25 June) until 30 July disease was assessed and green leaf area measured. The trial was harvested on 22 August 1980. Significantly greater yields and grain weights were obtained from plots sprayed with fungicide at GS 39 than from those sprayed at any other time or left unsprayed. Treatments made before symptoms of infection by S. nodorum developed (i.e. before GS 55) prolonged the duration of green leaf areas during the post‐anthesis period. Grain weight and yield increases were related closely to the duration of green leaf area above 75 96, but not to the amount of green leaf area at any single assessment nor to the subsequent degree of disease development.

The data on which this abstract is based form part of a continuing research programme, the results of which will be published in full at a later date. Full details on the 1980 results referred to above appear in the Annual Report of Long Ashton Research Station (1980).
EPIPRE: a Disease and Pest Management System for Winter Wheat Developed in the Netherlands1
Authors: ZADOKS J.C.
Published: April 2008

EPIPRE is a system of supervised control of diseases and pests in winter wheat. The participating farmers do their own disease and pest monitoring. Their field data are entered into a computer, which produces recommendations for treatments optimizing toward highest financial return of crop protection. Aphids and five fungus diseases are incorporated. In 1980, some 4 96 of Dutch winter wheat acreage was covered. On the average, EPIPRE recommendations saved some Dfl 85 (£15) per hectare.
Importance économique de la pourriture grise de la vigne1
Authors: MATHYS Par G.
Published: April 2008

L'évaluation des pertes de récoltes en poids et en qualité, imputables àBotrytis clnerea, ne fait guère l'objet de publications particulières. Cependant, les informations reçues de dix pays, en réponse à un questionnaire, permettent de situer l'importance qu'il faut attribuer à la pourriture grise. Le caractère insidieux du pathogène qui s'étend également aux sarments, bourgeons dormants et aux rafles appelle une grande prudence; et partant, une série d'applications fongicides coûteuses, atteignant parfois la moitié des frais globaux de protection. II est fait état des pertes en poids et en qualité qui, en l'absence de traitements spécifiques, peuvent être très sensibles suivant les régions et les cépages.
Relations entre le desséchement de la rafle et Botrytis cinerea sur raisins1
Authors: BRECHBUHLER Par Ch.
Published: April 2008

Le dessèchement de la rafle d' origine physiologique et la pourriture pédonculaire due au champignon Botrytis cinerea sont encore trés souvent confondus par les praticiens et techniciens. De ce fait, les differences et analogies dans les symptomes sont discutees. Le dessèchement de la rafle est surtout caractérisé par la date d' apparition des atteintes, dans les 15 jours qui suivent la mi‐véraison, et par la présence de nécroses bien localisées, sèches, a contours limites. De nombreux facteurs sont communs. Mais, contrairement à l' opinion encore très répandue, le dessèchement de la rafle ne favorise pas l' installation de B. cinerea. Certaines techniques, telles que l' effeuillage, le traitement a la gibbérelline, l' enlèvement de baies, réduisent les deux maladies. On constate alors un enrichissement en calcium et magnésium de la rafle qui s'accompagne d' un développement des faisceaux libéro‐ligneux dans le cas de la gibbérelline. L' importance économique de la pourriture pédonculaire est plus grande; les pertes peuvent s'elever jusqu'a 50–60 % de la récolte contre moins de 25 % par le dessèchement de la rafle. Le traitement des grappes à la véraison, avec un mélange d' un sei magnésien et d' un fongicide de la famille des imides cycliques, est efficace.
The Use of a Radioimmunosorbent Assay for Botrytis cinerea1
Authors: SAVAGE S.D. , SALL M.A.
Published: April 2008

A radioimmunosorbent assay was developed for Botrytis cinerea which can be used to detect as little as 100 ng of Botrytis mycelium (dry weight). Of 22 fungi tested in the assay, all significant reaction was restricted to members of the Sclerotiniaceae. No reaction was obtained with representative isolates of Aspergillus, Alternaria or Peiticillium. Other Botrytis species gave the most reaction relative to B. cinerea. and related genera such as Monilinia and Sclerotinia yielded small reactions. The assay can be used to detect fi. cinerea infection of grape berries when as little as 0.1 % of homogenate from infected fruit is mixed with homogenate from sound fruit to simulate a minor infection. The assay of free run juice from various lots of grapes was highly correlated with visual assessments of infection in the field. Pursuant to various theories concerning bloom time infection, the assay was used to analyse the B. cinerea content of immature berry tips and floral debris; however, no evidence of such colonization was obtained.
Résultats expérimentaux obtenus avec une formulation fluide d' iprodione contre la pourriture grise de la vigne. Influence de l'iprodione sur le développement des pourritures secondares1
Authors: CHALANDON Par A. , MARGOSSIAN A. , PAVIOT J.
Published: April 2008

Des études en laboratoire et en serre ont montré que la présence simultanée d' iprodione et d' huile dans un rapport déterminé au sein d' une formulation crème fluide améliorait la persistance d' action du fongicide. Cette formulation connue sous le numéro de code EXP 1861 et titrant 25 % d' iprodione a été expérimentée depuis 1977 contre la pourriture grise de la vigne (Botrytis cinerea). Sur une série de 25 essais de plein champ dont l' infestation des parcelles témoins est supérieure á 20 % (moyenne d' infestation 38,2 %), la répartition des essais en fonction des normes retenues par le « groupe de travail pourriture grise de la vigne » est la suivante: 22 essais sur 25 réalisés répondent au critere d' efficacité supérieure a 50 %, 18 essais sur 22 répondent au critère du niveau d'infestation inférieur á 20% dans la parcelle traitée. Cette expérimentation situe l' EXP 1861 a un niveau d' efficacite moyen de 75 % environ. Des essais spécifiques ont montré que cette formulation était sans effets phytotoxiques sur la vigne et que le produit n'affectait, ni le processus normal des fermentations, ni les qualityés organoleptiques des vins. Enfin, il faut signaler que l' EXP 1861 tout comme Rovral PM 50 possède une bonne activité sur les maladies causées par les champignons appartenant aux genres Rhizopus, Penicillium, Mucoret Alternaria qui peuvent, par les pourritures qu'ils developpent, entraîner des altérations graves dans les vins.
La protection du vignoble contre Botrytis cinerea en Italie du Nord et du Centre. Situation actuelle et perspectives d'avenir1
Authors: BISIACH Par M. , ZERBETTO F. , VERCESI A.
Published: April 2008

Les infections dues àBotrytis cinerea entraînent des pertes variables, mais souvent considérables. La diversité de la conformation orographique et la variabilityé climatique de chaque zone viticole qui en découle, d'une part, et la diversité des cépages, d'autre part, rendent difficile la mise en place d'un service central d'avertissement. La préférence est par conséquent donnée à la méthode de protection qui repose sur trois traitements appliques en fonction des stades phénologiques. Les viticulteurs les plus avertis sont cependant en mesure de combiner cette méthode rigide avec celle plus logique qui se base sur l'évolution des données météorologiques. Pour les cépages les plus sensibles et de haute qualityé, le programme de traitement contre B. cinerea est réalisé a l'aide de la vinchlozoline, qui permet d'obtenir des indices de protection de l'ordre de 80–90 %. Après six ans d'application des imides cycliques sur les mêmes vignobles expérimentaux, on n'a pas observé l'apparition de souches de B. cinerea résistantes à ces fongicides. Une expérimentation en cours est destinée à réduire le potentiel de l'inoculum hivernant, et examine les possibilityés de stopper une épidémie. Elle porte, de plus, sur l'emploi de mélanges de produits et sur l'alternance de ceux‐ci. Des perspectives intéressantes s'ouvrent par l'emploi d'antagonistes microbiens et par l'amélioration génétique.
Chemical Control of Botrytis cinerea on Grapes in New York (USA)1
Authors: PEARSON R.C.
Published: April 2008

Control of gray mold in New York vineyards is difficult to achieve at the present time. Benomyl‐resistant strains of Botrytis cinerea have been isolated from vineyards in all grape‐growing regions of New York State. Because of this resistance and lack of governmental registration of new fungicides, growers must choose among only moderately effective fungicides such as captan, folpet, dicloran and copper. Current research indicates that either vinclozolin or iprodione at 850 g/ha to 1100 g/ha applied twice, beginning at about 5 % sugar content and two weeks later, will provide excellent control of gray mold on ripening berries, whereas sprays applied at 5 % or 90 % bloom and at berry touch are not effective. An application of gibberellic acid (GA3) (10 or 25 (µg/ml) on Aurore (S.5279) at 10–15 cm shoot growth reduced the severity of gray mold on clusters of ripe fruit, but not the incidence of it. A single application of triadimefon at 30 mg/1 sprayed on Vignoles (Ravat 51), when fruit clusters averaged 17 % surface area infected with Uncinula necator and 2.6 % sugar content, retarded the development of powdery mildew and subsequent berry splitting, and ultimately reduced the severity of gray mold by 50 % at harvest, 6 weeks later.
Grey Mould Damage and Control in Hungary1
Authors: TOTH B.
Published: April 2008

Grey mould is one of the most important fungal diseases of grapevine, and for this reason the successful control of Botrytis cinerea determines the result of grape growing. As far as damage is concerned, the most important infection occurs at the end of flowering and just before ripening. The conidia of the fungus infect the berries through wounds, which may be caused by hail or storms, or by chewing insects, or also, most importantly, by physiological berry splitting. This occurs when a long dry period in summer is followed by a rainy autumn at ripening time. The prevention of wounds is one of the most important aspects of control. For the first half of the year, we propose using the traditional contact fungicides against grey mould. The use of benzimidazole‐type systemic fungicides is proposed only for the last two treatments, because they have a low persistence and because in this way we avoid the development of resistance to these systemic fungicides.
Protection of Vineyards from Grey Mould in Georgia (USSR)1
Authors: KUPARASHVILI O.G.
Published: April 2008

Grey mould is a very serious disease under the subtropical conditions of Georgia. While cultural methods and control of other pests and diseases offer some potential for control, fungicides play an important role and data are presented on the efficacy of several products and mixtures under Georgian conditions.
Botrytis cinerea and its Resistance to Dicarboximide Fungicides1
Authors: LORENZ D.H. , EICHHORN K.W.
Published: April 2008

In all vineyards in the Pfalz area (FRG) where the dicarboximide fungicides have been applied, resistant isolates can nowadays be found. These do not differ from the sensitive ones in uptake of the active ingredient of the dicarboximides or in the number of nuclei in spores or hyphal cells. The percentage of resistant strains decreases in the population when there is a long gap between applications of the fungicides. As a possible explanation, we have observed tendencies to resensitization in all resistant isolates. The degree of resensitization varies according to isolate.