bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of invasions by exotic plant pests
Authors: HONE J.
Published: April 2008

Quantitative aspects of the detection of invasion by exotic pests are reviewed. Equations are linked for estimating the expected number of occurrences of pests, and the probability of detecting at least one pest occurrence. The frequency distributions of the annual number of detections for some exotic plant pests were calculated and in 6 of 7 analyses were not significantly different from Poisson frequency distributions. The aim of early detection of invading exotic pests would be assisted by better surveillance schemes, better data bases of invasions and more sophisticated modelling of entry by pests.
Agrometeorology, modelling and forecasting within IPM in horticultural crops and vineyards1
Authors: EGGER E.
Published: April 2008

This summary presents the real possibilities for the use of agrometeorology in achieving IPM in horticultural crops and vineyards, and also the problems. Some examples of the practical application of forecasting models for fungal and insect pests are used to document the usefulness of this recently improved approach to modern phytotherapy, which aims to increase the effectiveness of treatments while simultaneously reducing their number. In this way one can obtain a reduced impact of chemical pollution on man and the environment. However, the practical requirements of IPM programmes must be emphasized and these set the standard for the type, quantity and quality of the meteorological data input. The contribution of biotic factors is compared with that of abiotic ones. Finally, the present needs of agrometorology in IPM are focused, with an outline of its future perspectives.
Prediction of codling moth egg hatch in Germany and Italy using the Californian forecasting model Bugoff21
Authors: BLAGO N. , DE BERARDINIS E.
Published: April 2008

The effectiveness of the Californian model Bugoff2 for Cydia pomonella was tested in Germany (4 years) and Italy (2 years), the Italian results confirming the German findings. In the first codling moth generation (air temperatures normally below 30 C) good agreement was found between field observations of egg hatching and the model's forecast. However, the model gave notable differences for the second generation, i.e. 3 weeks in Germany and 1 week in Italy, and a significant difference for the third generation in Italy. These divergencies arise from an overestimation of the development rate of the codling moth in Bugoff 2's heat unit table whenever air temperature exceeds the upper limit for development. As a result of modifications to Bugoff 2, an example of a better simulation of the codling moth egg hatch in Germany and Italy is discussed.
The development of weather‐related disease forecasts for vegetable crops in the UK. Problems and prospects1
Authors: HUMPHERSON‐JONES F. M.
Published: April 2008

Research on the development of weather‐related forecasters for major vegetable diseases started at HRI Wellesbourne (GB) in 1986. The research has concentrated on foliar fungal diseases of brassicas and leeks but in 1991 it is being extended to cover diseases of onions. Studies on the effect of climatic conditions on the development of the pathogens are made in controlled conditions and in infected field crops. The results of these studies are described for dark leaf spot (Alternaria brassicae and A. brassicicola) and white blister (Albugo candida) of brassicas and for leek rust (Puccinia porri). The problems of applying disease forecasters in vegetable crops are discussed.
MILVIT: un modèle descriptif et quantitatif de la phase asexuée du mildiou de la vigne. Présentation et premiers résultats de validation1
Authors: MAGNIEN C. , JACQUIN D. , MUCKENSTURM N. , GUILLEMARD P.
Published: April 2008

Depuis 1988, le Service français de la Protection des Végétaux travaille à la mise au point d'un modèle descriptif et quantitatif de la phase estivale du mildiou de la vigne, nommé MILVIT. MILVIT est un modèle fondé sur une structure compartimentée étroitement calquée sur le cycle infectieux de Plasmopara viticola. L'indicateur de risque retenu est le nombre de spores disponibles pour la pollution de la vigne. Pour son fonctionnement, le modèle utilise deux variables climatiques, la température et l'humidité relative mesurées toutes les 3 h. En 1990, ont été conduits les premiers travaux de validation. En Bourgogne et Charentes, le modèle a décrit correctement I'évolution qualitative de la maladie en repérant toutes les contaminations essentielles ainsi que les principales périodes de sporulation du champignon. L'évolution de la gravité des attaques de mildiou sur grappe a aussi été simulée de façon satisfaisante. En Languedoc, des imperfections ont été observées au niveau du compartiment‘contaminations’. En 1991, les travaux de validation seront poursuivis et une étude sera engagée pour faire évoluer MILVIT, modèle épidémique, vers un modèle d'aide à la decision.
Risks, forecasting and tactical decision‐making in integrated pest and disease management1
Authors: DAAMEN R. A. , RABBINGE R.
Published: April 2008

The uncertainty of pest and disease outbreaks and the associated damage (risk) may limit the adoption of integrated farming systems. This risk can be reduced by preventive practices and by a selective use of pesticides based on monitoring and forecasts. Whether forecasts based on agrometeorological data may reduce risk depends mainly on the strength of the weather dependency of the host and the parasite and whether outbreaks can be forecast accurately and in time to allow control action. Pests for which the weather only sometimes enables an outbreak, or which exhibit long incubation periods, are good candidates for forecasts based on weather. Epidemics of wheat diseases are discussed as an illustration.
Development of a forecasting model for scald, Rhynchosporium secalis, on rye in relation to climatic conditions1
Authors: WERRES G. , HINDORF H.
Published: April 2008

In a large‐scale forecasting project financed by the German Ministry of Agriculture, in collaboration with the National Plant Protection Service, data for modelling forecasting systems in field and horticultural crops are obtained and evaluated. Using climatic records from automatic weather stations and weekly disease assessments in the field, a practical model for forecasting Rhynchosporium secalis on rye has been established with a discriminant function in which temperature, leaf wetness and a disease index during the infection period were used as classification variables. This function decides on application of fungicide sprays.
A new approach to the use of meteorological and suction trap data in predicting aphid problems1
Authors: HARRINGTON R. , HOWLING G. G. , BALE J. S. , CLARK S.
Published: April 2008

The network of suction traps operated by the Rothamsted Insect Survey has provided records of aphid activity since 1965. Previous attempts to use this information with meteorological data for predicting aphid problems have concentrated mainly on simple linear regression techniques. In this paper the value of a more complex multiple regression approach is investigated using additional data from an increased range of sites, species and years. Data from 1966 to 1988 are used to produce models to predict the date of the first record of each of 49 aphid species at each of six sites. The models used were particularly successful in predicting the date of the first record at a range of sites in 1989 of four species: Myzus persicae, Macrosiphum euphorbiae, Sitobion avenae and Phorodon humuli.
Règles de décision pour la réduction des traitements contre Sclerotinia sclerotiorum sur colza en fonction des conditions climatiques1
Authors: GOHARI H. , BALLESTER F.
Published: April 2008

La relation entre les données climatiques (température et précipitation) et la gravité des attaques de Sclerotinia sclerotiorum sur colza a étéétudiée à partir des observations faites dans le département du Cher (FR) depuis 1983. Un modèle de régression à deux variables climatiques avec un R2 de 0,72 est présenté et son utilisation pratique est discutée. Sont également présentés des critères de décision basés sur des conditions climatiques défavorables au développement de la maladie. L'ensemble de ces critères peut constituer un système d'aide à la décision qui, appliquéa posteriuri sur ces données, semble plus efficace que le modéle de régression multiple.
Simulation model of Oulema melanopus in the winter‐wheat ecosystem1
Authors: ZEMANKOVICS M. HUNKÁR
Published: April 2008

Simulation system sonches (Simulation of Nonlinear Complex Hierarchical Ecological Systems) is a tool for computer‐aided experimental investigation of the dynamic behaviour of ecological systems. A winter‐wheat agroecosystem was modelled with the help of sonches. The whole model consists of several submodels. One of them is the growth‐development model of winter wheat itself. The others are pest models. The model of cereal leaf beetle (Oulema melanopus) was investigated. The main driving force in the model is daily mean temperature. The temperature inside the plant canopy is different from the temperature outside it (at the meteorological station). A microclimate model was used to modify the measured temperature values. Simulation experiments were carried out to show the effect of using microclimate data instead of standard meteorological data. The difference between the temperature inside and outside the canopy depends on radiation. The days of the vegetation period were classified by sunshine duration: clear, cloudy and overcast days. Winter wheat treated with different amounts of nitrogen fertilizer has a different canopy structure. The microclimate inside the canopy alters according to density. Results of simulation experiments in the form of population dynamics are presented.
Analysis of leaf wetness in the rice crop caused by dew formation—a simulation study1
Authors: WEIHONG LUO , GOUDRIAAN J.
Published: April 2008

Daily dew amount and dew duration were simulated using a multi‐layer energy balance model. Two simplifications were made in the model and validated. First, the simulation results showed that daily weather data instead of hourly weather data could be used to simulate dew formation in crops, which was validated by measurements for short grass vegetation. Second, estimation of the total daily dew period was shown to be possible on the basis of nightly dew formation only. This simplification was possible on the basis of the existence of a linear relationship between the dew period after sunrise on the one hand and the dew amount at sunrise on the other. The multi‐layer crop microweather model becomes much smaller and simpler (and is then called the SIMPLE model) if only night dew formation is simulated. Our results will make it possible to incorporate the SIMPLE model into a fungal disease epidemic model and a basic crop growth model.
Syséme d'avertissement destinéà la lutte contre le feu bactérien1
Authors: JACQUART‐ROMON C. , PAULIN J. P.
Published: April 2008

Une des principles difficultés de la lutte contre le feu bacterien est liée à l'irrégularité de la gravité de la maladie, qui entraîne une incertitude dans le choix de la décision a prendre. Les systèmes d'avertissement ont pour but de résoudre de telles difficultés. Dans cet article, nous décrivons un système d'avertissement destinéà faciliter la lutte contre le feu bactérien. Un potentiel climatique base sur des paramétres climatiques passés et sur des prévisions (températures, pluies, orages) est estimé, ainsi qu'un potentiel d'inoculum dérivé de la connaissance précise de l'activité de la maladie dam la région. Les potentiels sont calculés, a partir de données simples et rapidement disponibles, par un programme prévu pour être utilisé sur micro‐ordinateur. Ils sont combinés pour determiner un risque général de feu bactérien, transformé ensuite en conseils pour la lutte. Le système proposé a montré qu'il permet une meilleure lutte contre le feu bactérien du poirier qu'un programme conventionnel, basé sur des pulvérisations à des dates calendaires.
From CLIMEX to PESKY, a generic expert system for pest risk assessment1
Authors: SUTHERST R. W. , MAYWALD G. F. , BOTTOMLEY W.
Published: April 2008

CLIMEX, a climate‐matching model, is described in relation to pest risk assessment. The rationale for the development Of CLIMEX is given and its various functions are illustrated with examples, using the Colorado beetle Leptinotarsa decemlineata. The beetle's climatic requirements are first inferred from its native distribution in North America. They are then used to project the relative favourableness of Europe and Asia for population growth and persistence. The role is illustrated Of CLIMEX, in association with PESKY, a prototype version of a generic expert system for pest risk assessment, in the assessment of the risk of the beetle being transferred from France to China. Finally, CLIMEX is used to search for places in North America with climates best matching that of Beijing (CN), in order to target collection of possible biocontrol agents for use against the beetle in that area, should it become established there.
Application of high‐resolution weather data to pest risk assessment1
Authors: ROYER M. H. , YANG X. B.
Published: April 2008

Landscape maps of pest risk in the northeastern USA were produced for a hypothetical case study of an exotic plant disease (soybean rust) during the 1990 season. Published relations between the disease and a recently available high‐resolution weather database were used to generate the maps. The landscape maps depicted patterns of risk using color classes overlaid with county boundaries at a spatial resolution of 1 km. The potential geographical impact of the exotic disease was estimated by interpreting a series of maps during a growing season.
Use of multispectral radiometry in wheat yellow rust experiments1
Authors: HANSEN J. G.
Published: April 2008

Winter‐wheat field fungicide experiments were monitored by multispectral radiometry to determine yellow rust impact on crop growth and to predict yield loss caused by disease. Spectral reflectance data were highly correlated with yellow rust severity. Linear regression models with spectral ratios as independent variables explained 90–93% of the variation in yield between plots with different treatments of fungicide. The area under the NIR/Red curve, calculated from heading to soft‐dough growth stages, was a good predictor of yield loss determined at harvest.
Clavibacter michiganensis ssp. insidiosus in lucerne seeds
Authors: NÉMETH J. , LASZLO E. , EMÖDY L.
Published: April 2008

Bacterial wilt is a serious disease of Iucerne. Although there are several ways to transmit the pathogen, seed transmission is practically the only way to introduce the bacteria to previously free areas. In this work, naturally infected seed material and commercial seed lots have been screened by a combination of immunofluorescence (IF) staining and dilution plating. Isolates were confirmed by biochemical characterization and finally by artificial infection of lucerne seedlings. For seed lots free from the pathogen, a diagnosis can mostly be achieved within 2 days. The culture step is necessary only if IF staining is not unequivocally negative, and the full procedure has to be run only for a small portion of the samples. The proposed seed assay provides a reliable alternative to the visual inspection of lucerne fields to fulfil the phytosanitary requirements for Clavibacter michiganensis ssp. insidiosus.
New quarantine glasshouse pests in Poland and coloured sticky traps for their monitoring1
Authors: BARANOWSKI T. , DANKOWSKA E. , GÓRSKI R.
Published: April 2008

Trapping methods are being evaluated in Poland in connection with the addition of the following pests to the new Polish Quarantine List: Liriomyza trifolii, L. sativae, L. huidobrensis, Amauromyza maculosa, Thrips palmi, Frankliniella occidentalis, Bemisia tabaci. Variations were observed in the response of F. occidentalis, Trialeurodes vaporariorum and Bradysia spp. to colour, size and method of hanging of the traps. The highest numbers of F. occidentalis were found on blue traps of different shades, of T. vaporuriorum on yellow traps, and of Bradysia on orange and yellow traps.
Quantitative and qualitative analysis of accidental insect pest introduction into Switzerland and its implications for plant protection1
Authors: FREY J. E. , MANI E.
Published: April 2008

The purpose of this study is to assess the characteristics of accidental introduction of pest organisms into Switzerland by means of international plant trade, and to discuss its consequences for the development of plant protection strategies. We found substantial levels of infestation in samples of all producing countries included in the study. Since the use of synthetic pesticides is the main basis of pest control in the ornamental industry, the results of this study indicate that chemical pest control has reached a limit above which no further reduction of pest population levels is possible. The increased pesticide tolerance of many arthropod pests is mainly due to increased levels of resistance to pesticides caused by their excessive use. Therefore, alternative methods supplementing pesticide use are required to develop an optimal pest management strategy for the future. It is proposed that, in the Swiss ornamental production industry, pest monitoring should be the first step in this direction.
Western flower thrips (Frankliniella occidentalis)—occurrence and possibilities for its control in Hungary1
Authors: SZABÓ P. , CEGLARSKA‐HÓDI E.
Published: April 2008

Frankliniella occidentalis was first recorded in Hungary in 1989. The pest has endangered the mass‐rearing and distribution of the biological control agents Encarsia formosa and Phytoseiulus persimilis being conducted at the Hódmezövásárhely Institute. Different insecticide active ingredients were studied for elimination of the pest from experimental glasshouses and new methods for monitoring populations of the new thrips. The fungus Verticillium lecanii has been tested as an indirect control agent.
Biological control of Frankliniella occidentalis on ornamental plants using predatory mites1
Authors: GLOCKEMANN B.
Published: April 2008

The results of four experiments on biological control of Frankliniella occidentalis on flowering Saintpaulia ionanfha and one on pelargonium are presented. Three species of predatory mites were used for the experiments: Amblyseius barkeri, and two soil‐dwelling species Hypoaspis aculeifer and H. miles. Three releases each of 15 H. miles per saintpaulia plant at weekly intervals did not have any effect on the pest population. In two experiments on saintpaulia, 10 females of H. aculeifer per plant were released weekly for a period of 10 weeks. The increase of thrips population was slowed down for some weeks and population peaks were diminished. However, this treatment failed to keep the pest at a low level. In one experiment, 15 A. barkeri per saintpaulia plant were released weekly for 10 weeks. Thrips population dynamics was slowed down for about 4 weeks, but again the treatment failed to keep the pest at a low level. In one experiment on pelargonium, 15 A. barkeri per plant were released fortnightly for 10 weeks. An effect was obvious in both replicates. Pest populations hardly increased on the plants treated with the biocontrol agent but increased significantly in the controls. The reasons for these results and differences are discussed. The suitability of these three species for production and use as biocontrol agents is discussed.
Biological control of pests in Swedish pot plant production1
Authors: NEDSTAM B.
Published: April 2008

Biological control of glasshouse pests is nowadays an important factor in the production of pot plants in Sweden. During 1990, more than 100 growers applied one or more methods of biocontrol, some only in propagation units but many during the entire production of several crops. Poinsettia is the major crop in this context. Eighty growers were interviewed about their experiences of various biocontrol methods. The use of Neoaplectana carpocapsae against sciarids and Otiorhynchus sulcurus was the most popular and reliable method. Next comes Encarsia formosa against whiteflies. Other methods include Verticillium lecanii against whiteflies and thrips, Aphidius matricariae against aphids, and predatory mites against thrips and spider mites.
Biological control of aphids on capsicum1
Authors: HOMMES M.
Published: April 2008

During four growing periods from 1986 to 1989, biological pest control on capsicum was investigated in glasshouses under practical conditions. Aphids, mainly Myzus persicae, caused the most serious pest problems. As biological control agents, the commercially available predatory gall midge Aphidoletes aphidimyza and the green lacewing Chrysoperla curnea were used. Both these natural enemies were released according to the recommendations of the producers. For the releases of the gall midges, small peat samples containing the pupae of the predator were placed at a few spots in the glasshouse (1–2 pupae per m2). The lacewings were introduced as eggs on small mesh‐pieces which were placed on every second plant (10–20 eggs per m2). In these experiments, control of the aphid populations was effective only if the two predators were introduced early and were released several times. During the summer, other natural enemies such as parasitic wasps, syrphids, ladybirds and predatory bugs immigrated from outdoors and enhanced the biological control of aphids.
Release of Aphidius matricariae for control of Myzus persicae in glasshouses1
Authors: WICK M.
Published: April 2008

Aphidius matricariae, the most effective antagonist of Myzus persicae, has been released in experiments to control this aphid on capsicum, Anthurium andreanum and Ficus lyrata. In all cases, effective short‐term as well as long‐term control has been achieved through an infestation‐linked application of the parasite, at parasitoid‐host ratios from 1:5 to 1:50. Control experiments in capsicum over 31 weeks showed effective control of M. persicae by A. matricariae, even at a high infestation level. Chemical insecticides were not needed against aphids until week 26, when it became necessary to avoid damage due to mass propagation of naturally occurring Aphis gossypii and Macrosiphum euphorbiae. The results show that, with increasing complexity of biological control methods, the species diversity of aphids increases their significance as pests. In particular, biocontrol of aphids seems to necessitate the use of several antagonists.
Predators with a future as bioagents against glasshouse pests1
Authors: LOGINOVA E. , MATEEVA A.
Published: April 2008

As a result of the application of Encarsia formosa, Phytoseiulus persimilis and Bacillus thuringiensis, and of the decreased use of pesticides, we have observed the spontaneous appearance of natural enemies not normally present in Bulgarian glasshouses. Clitostethus arcuatus has proved a competitive species with E. formosa on Nicotiana glauca, green capsicum and Hibiscus syriacus, attacked by Trialeurodes vaporariorum. On cucumber and capsicum plants infested respectively by Aphis gossypii and Myzus persicae, Cryptolaemus montrouzieri was established after spontaneously entering an experimental glasshouse. Some trials were carried out with the polyphagous bug Podisus maculiventris under laboratory conditions. It was able to use larvae of T. vaporariorum, M. persicae and A. gossypii as prey. On this basis, it seems quite promising to include this predator in IPM programmes as an additional bioagent against certain glasshouse pests during the autumn‐winter‐spring period.
Biological means of plant protection in glasshouses in Belarus1
Authors: SIDLYAREVICH V. I. , KOROL I. T. , KOMAROVA M. S. , NOVIKOVA O. T. , ROMANOVETZ Z. A.
Published: April 2008

Biological control methods introduced and developed for Belarussian glasshouse crops are described. The agents used against arthropod pests include the natural enemies Phytoseiulus persimilis, Encarsia formosa and Amblyseius spp., the fungi Verticillium lecanii, Beauveria bassiana and Aschersonio, and the preparation Bitoxibacillin (based on Bacillus thuringiensis var. thuringiensis). Against fungal pathogens, Trichodermin (based on Trichuderma Iignorum) and peat oxyhumates are used.
Integrated pest‐management approaches in orchard, cereal and potato protection in Poland1
Authors: LIPA J. J.
Published: April 2008

With its total area of 312,683 km2 and a population of about 39 million people, the area of agricultural land per person in Poland is about 0.47 ha. The yields of basic crops are rather low and the losses due to pathogens, animal pests and weeds are high. The use of pesticides is about 1.0–1.3 kg a.i. per ha and this gives a good starting point for integrated pest management (IPM) in the production system of various crops. IPM in glasshouse crops reached the level of 500 ha per year. An IPM approach against codling moth (Cydia pomonella) in orchards allowed a reduction by 70% in the number of insecticide treatments. In the case of apple scab (Venturia haequalis), the IPM approach allowed a reduction in the number of fungicide treatments by 30% on an area of 100,000 ha. In respect to small grains, the IPM approach concerns rational use of fungicides and herbicides in winter wheat and barley. In potato protection, the IPM approach mainly concerns Colorado beetle (Leptinotarsa decemlineata), which at present is controlled by chemical insecticides on 77% of the potato area. Special research and demonstration IPM programmes sponsored by USDA/AID in Central and Eastern Europe will be operational during 1992/1995 and will concern orchards (apple, pear), small grains (wheat, barley) and potatoes.
Scientific issues arising from the use of the International Plant Protection Convention definition of a quarantine pest
Authors: PHILLIPS D. , CHANDRASHEKAR M.
Published: April 2008

This paper examines some of the issues arising from the use of the IPPC definition of a quarantine pest. Using hypothetical case studies of pathogens and their hosts, the authors examine some of the potentially contentious issues that are likely to arise from the application of the definition. Proposals for resolving these issues are suggested. To further simplify the application of the IPPC definition in international plant quarantine, the authors present diagrams setting out the decision‐making pathways that can be followed.
PROGEB—a model‐aided forecasting service for pest management in cereals and potatoes1
Authors: GUTSCHE V.
Published: April 2008

PROGEB integrates forecasting models for the main pests of potatoes and cereals in Germany: PHYTEB for Phytophthora infestans, SIMLEP for Leptinotarsa decemlineata, SIMCERC for Pseudocercosporella herpotrichoides, SIMERY for Erysiphe graminis. All models follow the same philosophy, and have been implemented on PCs following a uniform design. The system is illustrated by the example of P. infestans control.
PC‐based disease warning systems for use by apple growers1
Authors: XU X. M. , BUTT D. J.
Published: April 2008

To protect apple orchards from diseases efficiently, growers need farm‐based rather than regional disease warning systems. This paper describes three PC‐based systems from Horticulture Research International (GB). These systems, VENTEM, PODEM and NECTEM, provide warnings in the form of infection alerts and disease forecasts of Venturia inaequalis (scab), Podosphaera leucotricha (powdery mildew) and Nectria galligenu (European canker and fruit rot), respectively. The modular structure, operation and practical implementation of these systems are described and compared. A major input is weather data recorded automatically by Metos weather stations sited on farms. Each system has a weather‐driven dynamic model simulating inoculum production and the infection process. The systems use information on quantity of inoculum, cultivar susceptibility and other host factors to produce disease forecasts which are specific to individual orchard blocks and cultivars.
An advisory service for the occurrence of Phytophthora infestans on tomato in Emilia‐Romagna region1
Authors: BUGIANI R. , CAVANNI P. , PONTI I.
Published: April 2008

The Emilia‐Romagna region is one of the leading areas in Italy for its high production of industrial tomatoes. A warning service for the occurrence of late blight caused by Phytophthora infestans has been operating for 3 years in the region. Its aim is to reduce the number of sprays which are usually carried out on tomato crops to prevent the disease (7–8 sprays depending on year and area). Climatic data from weather stations covering all the region is used by the warning service to inform farmers every week of the risk of disease occurrence and provide them with precise spray recommendations for blight control. A forecasting model based on climatic data (IPI Model; Infection Potential Index) has been elaborated by the Plant Protection Service of Emilia‐Romagna region and is now used together with a network of unsprayed tomato plots and, in the high‐risk areas, with aerobiological monitoring of P. infestans sporangia. The IPI Model uses daily data on temperature, RH and precipitation, and shows good reliability for ‘negative prognosis’ of the disease; the other forecasting parameters become more important when the risk is higher. This warning service has allowed growers to reduce sprays by 50% on average. Further reduction in treatments should be possible, especially in low blight‐risk areas.
Geographic Information Systems for localized pest predictions1
Authors: SEEM R. C.
Published: April 2008

Geographical Information Systems (GIS) provide a means of visualizing and modeling the distribution of plants and pests as well as other important attributes of crop production. GIS uses multiple data bases, with each value referenced to a common coordinate system; data can be combined in the form of thematic maps. With the addition of weather and elevation data at the same resolution and coordinate system, pest development can be monitored and predicted over large areas but with local detail. GIS has been used for predicting phonological development of gypsy moth and other important insect pests. Similar approaches have been used for plant diseases such as potato late blight and apple scab. An important feature of GIS for pest prediction is the ability to assess risk of pest development. Most GIS programs also have a set of tools for spatial analysis of data. Examples of all the features of GIS are illustrated using a GIS that runs on a DOS personal computer.
An electronic picture data base in plant protection1
Authors: GRÖNTOFT M.
Published: April 2008

To facilitate the use of plant protection pictures stored in many different files and places, a project has started in the Nordic countries to collect digital copies of pictures and distribute them on CD. Kodak's newly introduced Photo CD system will be used together with a uniform way of describing the subject of the pictures. The picture description is then the key to find it in a data base. The aim of the Nordic Picture Library is to select and store digital copies which give a varied view of a plant or a plant disease from different perspectives.
PRO_PLANT—a computer—based decision‐support system for cereal disease control1
Authors: FRAHM J. , VOLK T.
Published: April 2008

The task of the knowledge‐based advisory system PRO_PLANT is to help farmers reduce to a minimum the input of fungicides, and in later stages all pesticides, while giving as good economic returns as high‐input routine sprays with their potential environmental hazards (e.g. ground and surface water contamination). The system was first developed for cereal diseases and is now (till 1994) being extended to the most important pesticide applications on field crops (cereals, maize, rape, potato, sugarbeet). It can be used by consultants or farmers as a stand‐alone version. PRO_PLANT at present consists mainly of disease‐specific knowledge bases for diagnosis of fungus infections in cereals and rules for optimized fungicide treatments. The scientific basis has been derived from expert knowledge and field trials over several years, and the knowledge representation is rule‐based. During a consultation, information on the field, cultivar resistance, seed treatments and fungicides is considered. Necessary weather data comes from the German Weather Service via BTX or from a small home‐run weather station. The prototype was first tested in 1991 and an improved version was then tested in 1992 with 40 consultants and 30 farmers. In 1993, the system will be used by the advisory service of Nordrhein‐Westfalen and commercially distributed to farmers.
Integrated pest management in olive in the Mediterranean area1
Authors: CIVANTOS M. , CABALLERO J. M.
Published: April 2008

The FAO Interregional Cooperative Research Network on Olives is working on plant protection with the main objective of setting up an integrated pest management system aimed at controlling the main insect pests attacking Mediterranean olive orchards. The study of the factors controlling populations of both olive pests and their natural parasites and predators has therefore taken a great share of that cooperative effort. This paper reviews the work developed so far, while describing the computerized pest management programme now in use in Spain. This is directed by the national and some regional Plant Protection Services and based on the cooperation of olive growers' associations named Agrupaciones para Tratamientos Integrados (ATRIAs). Each ATRIA provides the meteorological and insect population data needed for plant protection researchers to take decisions about where and when to treat each pest.
Possible dissemination of Spilocaea oleagina conidia by insects (Ectopsocus briggsi)1
Authors: DE MARZO L. , FRISULLO S. , LOPS F. , ROSSI V.
Published: April 2008

Ectopsocus briggsi was recognized as a probable agent in dispersal of Spilocaea oleagina. Conidia of the fungus were found on the body, inside the insect and in its excrement.
Efficacité de quelques fongicides cupriques à l'égard de Spilocaea oleagina
Authors: BOURBOS V. A. , SKOUDRIDAKIS M. T.
Published: April 2008

Spilocuea oleagina provoque en Crète des dégâts importants sur les cultivars d'olivier Mastoidis et Kalamon. Les fongicides cupriques suivants ont été testés contre la maladie: sulfate de cuivre (BBS 25), oxychlorure de cuivre (Virifix 50), sels cupriques des acides gras et résineux (Tenn Cop 5E) et sulfate ammoniacal de cuivre (Copac E). Deux traitements ont été effectués pendant les périodes critiques pour la Crète (début octobre, fin février) sur des arbres du cv. Kalamon. L'efficacité a étéévaluée par dénombrement des feuilles infectéès et des taches par feuille, sur échantillons prélevés dans la couronne des arbres traités. Pour estimer l'action phytotoxique des fongicides testés, on a ramasséà l'aide d'un filet plastique toutes les feuilles tombées. Les sels cupriques et le sulfate de cuivre ont montré la meilleure efficacitéà l'egard du pathogène. On a constaté de plus, 8 mois après le premier traitement chimique, une chute négligeable des feuilles saines.
Virulent and avirulent isolates of Pseudomonas syringae subsp. savastanoi as colonizers of olive leaves: evaluation of possible biological control of the olive knot pathogen1
Authors: VARVARO L. , MARTELLA L.
Published: April 2008

The epiphytic survival of virulent and avirulent (indoleacetic acid‐deficient mutants) isolates of Pseudomonas syringae subsp. savastanoi, and their ability to colonize the olive phylloplane, was monitored for up to 30 days after artificial inoculation of several olive cultivars. After an initial decrease in numbers, the virulent bacteria multiplied and established a potential inoculum on olive leaf surfaces. In contrast, the numbers of avirulent bacteria rapidly diminished, so that they were eventually no longer detectable. Under the conditions used in this study, none of the avirulent mutants (producers or non‐producers of bacteriocins) were able to compete with or successfully to inhibit the virulent isolate in vivo. This was probably due to the lack of epiphytic multiplication of the avirulent mutants.
Dieback symptoms on olive trees caused by the fungus Eutypa lata1
Authors: RUMBOS I. C.
Published: April 2008

The fungus Eutypa lata was isolated from olive trees for the first time in 1988 from two young 3‐year‐old trees. It was evident that the infection was initiated from the graft union. The trees were also infected by Armillaria mellea. In a second case in 1991, extensive cankers were observed along the branches which often were girdled and died. The infected area extended from the bark into the sapwood and even into the heartwood. Cultures made on potatodextrose agar from the margin of necrotic and healthy tissues resulted in typical colonies of the fungus E. lata, as well as of Verticillium dahliae. The colonies of E. lata produced the characteristic pycnidia of the anamorph Libertella blepharis 3–4 weeks later. Pathogenicity tests made on olive, apricot, almond and walnut trees resulted in the death of the inoculated twigs or in canker formation and extensive brown discoloration of the wood.
Plant parasitic nematodes associated with olive1
Authors: LAMBERTI F. , VOVLAS N.
Published: April 2008

Over 70 species, belonging to 33 genera, of plant parasitic nematodes have been reported in association with olive. Several species of Helicotylenchus have been observed to cause root necrosis and considered capable of affecting olive tree growth. Three species of Meloidogyne (M. incognita, M. lusitanica and M. javanica) were responsible for heavy galling and growth retardation in inoculation trials and natural infestation. Pratylenchus vulnus has been demonstrated in inoculation trials as a potential pathogen of olive. Xiphinema species commonly occur around olive roots and X. elongatum has been shown to affect olive plant growth. Several sedentary plant nematodes attack olive. Tylenchulus semipenetrans infects olive in California (US) and Italy. Trophotylenchulus saltensis was described from olive roots in Jordan and a cyst nematode, Heterodera mediterranea, was shown to feed and multiply on olive roots. The cortical feeding cells of roots fed upon by Gracilacus peratica showed thickened and lignified wall near the penetration points of the stylet and those exposed to Ogma rhombosquamatum also presented hypertrophic nuclei and nucleoli. Rotylenchulus macrodoratus induces the formation of an enlarged mononucleate stelar or cortical ‘nurse cell’ with dense cytoplasm and hypertrophic nucleolus.
Viruses and virus‐like diseases of olive1
Authors: Barba M.
Published: April 2008

Partial paralysis, leaf malformation, sickle leaf and infective yellowing are diseases of possible virus etiology recorded in different areas where olive is cultivated. Several attempts to reproduce by grafting the symptomatology observed in the field did not give completely satisfactory results. Attempts to isolate and identify the causal agent of these diseases also failed. Only in 1976 was a virus isolated in Italy from an olive tree, cv. Correggiolo, which did not however show any symptoms. The virus was identified as a strain of strawberry latent ringspot nepovirus (SLRV), which is present in Italy on a few other fruit trees (peach, cherry). On olive, SLRV is found in central Italy and has only in one case been associated with a specific malformation of the leaves and fruits. Since this first report, several other viruses have been isolated from olive trees which did not, anyway, present any symptoms of virus disease.
Olive sickle leaf symptoms widespread in Greece1
Authors: Kyriakopoulou P. E.
Published: April 2008

Symptoms of olive sickle leaf, a disorder of olive considered to be of virus or virus‐like etiology, have been observed in Greece since 1980. Surveys at many places in Attiki, Peloponnisos and Makedonia regions showed symptoms in all cases, on cultivars Kalamon, Koroneiki, Manaki and Megaritiki. The frequency of symptom occurrence in individual trees and the intensity of symptoms varied from year to year, and 1981 was the year with the most frequent and strongest expression of the disorder. The proportion of affected shoots per tree usually varies between 5 and 90%.
SDS‐PAGE: a tool to discriminate Xylella fastidiosa from other endophytic grapevine bacteria*
Authors: BAZZI C. , STEFANI E. , ZACCARDELLI M.
Published: April 2008

There is a real risk of introducing Xylella fastidiosa into the EPPO region where this quarantine pest has not yet been found and constitutes a serious threat to the Mediterranean grapevine industry. Direct isolation of endophytic bacteria from imported propagation material, combined with one‐dimensional SDS‐PAGE of the total soluble proteins of the bacterial cell envelope, can be considered as a test to be used in grapevine certification schemes. The gel electrophoretic pattern of Xylella fastidiosa is characterized by a constant distribution of 14 major diagnostic bands. Even without gel scanning, this relatively simple technique allows discrimination between grapevine strains of X. fastidiosa and other xylem‐inhabiting, slow‐growing bacteria.
Plane decline in European and Mediterranean countries: associated pests and their interactions
Authors: ANSELMI N. , CARDIN L. , NICOLOTT G.
Published: April 2008

Surveys on the spread of the main pests of plane (Platanus spp.) and on their influence on the decline of this genus in recent years have been carried out in various European countries. Of the primary pests which have been detected, Ceratocystis fimbriata f.sp. platani, agent of canker stain, has spread through several of the northern Mediterranean countries, causing death of trees; Gnomonia platani, agent of anthracnose, has spread mainly in the north‐central Mediterranean areas; Microsphaera platani, agent of powdery mildew, has spread throughout almost all Mediterranean countries; so also has the insect Corythucha ciliata, which causes yellowing of the foliage. On trees declining under the interaction of these pests, secondary pests, agents of bark necrosis and, above all, of wood decay, are often detected. Ganoderma spp. are the main wood‐decaying pathogen and can cause lethal root rots, especially if favoured by various kinds of stress. The trends and interaction of these pests in northern Italy are considered and control measures are discussed.
Pictorial key to the economically important species of Thysanoptera in Central Europe
Authors: MORITZ G.
Published: April 2008

A pictorial key allows determination of 70 economically important species in 34 genera of the order Thysanoptera in Central Europe. The identification of larva, propupa and pupa stages is possible at the family level.
Detection and characterization of plum pox potyvirus isolates from southern Germany by polymerase chain reaction (PCR)1
Authors: KRCZAL G. , AVENARIUS U.
Published: April 2008

Plum pox potyvirus (PPV) isolates show quantitative and qualitative differences in host plants, symptomatology, aphid transmissibility and molecular biology. In order to gain an overview of the different PPV strains that exist in Germany, several PPV isolates, mainly deriving from southern Germany, were analysed by polymerase chain reaction (PCR), the reaction yielding a 243 bp product. All PPV isolates tested were amplified and the amplified fragments were analysed by restriction endonuclease digestion. An Rsa I restriction site polymorphism in the amplified fragments allowed the discrimination of two groups of isolates.
Correlation entre trois techniques permettant de différencier les isolats du plum pox potyvirus1
Authors: BOUSALEM M. , CANDRESSE Th. , QUIOT‐DOUINE L. , QUIOT J. B.
Published: April 2008

Une collection d'isolats du plum pox potyvirus provenant de differents foyers de sharka a été comparée par trois techniques de caractérisation: mobilitéélectrophorétique de la protéine capside mesurée à partir d'extraits bruts en électro‐immunoblot; propriétés antigéniques des extrémités N et C de la protéine capside évaluée à l'aide d'un sérum polyclonal préalablement épuisé par chromatographie d'affinité; présence d'un site de restriction spécifique sur la partie C‐terminale de la protéine capside détecté après amplification par immunocapture‐PCR. Une corrélation complète a été trouvée entre ces trois méthodes. Elle confirme l'existence de deux groupes majeurs de PPV analogues aux sérotypes M et D de Kerlan & Dunez.
Evaluation de la résistance d'une lignée transformée de Nicotiana benthamianaà l'inoculation et à l'acquisition du plum pox potyvirus par puceron1
Authors: LABONNE G. , RAVELONANDRO M. , YVON M. , ADAMOLLE C. , QUIOT J. B. , MONSION M.
Published: April 2008

La transformation de plantes par intégration du gène codant pour la protéine capside d'un virus dans leur génome permet de générer des plantes résistantes à certains virus. Pour évaluer l'intérêt de cette approche vis‐à‐vis du plum pox potyvirus (PPV), des plants de Nicotiana benthamiana, espèce herbacée facilement manipulable et sensible au PPV, ont été transformés. Une lignée a été sélectionnée pour son comportement à l'inoculation par le PPV. La résistance de cette lignée à l'inoculation par puceron et sa capacitéà servir de réservoir de virus pour les pucerons ont été mesurées en utilisant le vecteur Myzus persicae. La lignée transformée est apparue aussi sensible que la lignée non transformée à l'inoculation du PPV par puceron. Par contre, le virus est plus facilement acquis sur la lignée non transformée que sur la lignée transformée. Sur cette derniére, les pucerons acquièrent le virus sur les feuilles proches des feuilles inoculées, mais non sur les feuilles suivantes. L'analyse de la répartition du virus dans les plantes par immunoempreinte montre que le PPV se trouve dans toutes les parties des plantes non transformées, alors qu'on ne le trouve, de facon localisée, que dans quelques feuilles des plantes transformées. Parallèlement aux résultats des essais par inoculation mécanique, cette analyse confirme le blocage de la systémie du PPV dans les plantes transformées. L'immunoempreinte permet l'identification rapide de ce phénomène.
Susceptibility of some North American and Yugoslav plum cultivars to plum pox potyvirus in Poland1
Authors: ZAWADZKA B. , ROZPARA E. , GRZYB Z. , MALINOWSKI T.
Published: April 2008

All North American plum cultivars investigated in Poland for their reaction to plum pox potyvirus appeared to be susceptible, showing severe symptoms on the leaves. Fruits of cvs Valor and Empress were also heavily damaged. Of the Yugoslav cultivars evaluated, Cacanska Najbolja was most tolerant whereas Cacanska Rodna appeared to be most sensitive to PPV.
Recent results on resistance to plum pox potyvirus in plum in Romania, and on the epidemiology of the disease1
Authors: MINOIU N.
Published: April 2008

Of 50 plum cultivars investigated for infection by plum pox potyvirus (PPV), three had the virus in the latent state (Mansan, Twilight and Frontier), 19 showed very slight or slight symptoms on leaves, 16 showed moderate symptoms and 12 severe symptoms. No symptoms were seen on fruits of cvs Diana, Ialomita, Abundance, Silvia, Mont Royal, Red Glow, Locale de Turt, Krikon and Blue Free. Slight symptoms present only on the fruit skin were noted on cvs Gras ameliorat, Seneca, Rosior de Zalau, Prun protuberat, Anna Späth, Early Rivers, LU, Pitestean, Pamiat Timiriazeva, Dunarea Albastra (Blue Danube), Gras romanesc and others. Few plum cultivars had sensitive or very sensitive fruit. Most hybrids obtained in Romania are tolerant in terms of symptoms on fruits. Of the rootstocks, Red Dwarf Myrobalan, Buburuz, Marianna and P. besseyi showed no or very slight symptoms. Plum plantations located close to a PPV infection source for 6–9 years were 13.2–45.5% infected. Trees planted in an infected orchard were up to 74% infected in 6 years.