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The use of biological control agents (BCAs) is supported bt Directive 128/2009/EC on the Sustainable Use of Pesticides, which gives priority to non-chemical methods for disease control.

È noto che la resistenza alle malattie fungine, compresa la peronospora, può essere indotta da fattori fisici, chimici e da microrganismi (o loro composti e metaboliti). Anche vari prodotti fertilizzanti arricchiti di amminoacidi, elementi minerali o metalli vengono proposti come induttori di resistenza, spesso in abbinamento a fungicidi. Un fertilizzante organo minerale che contiene acidi gluconici, oligosaccaridi e zuccheri riducenti (ActiclasterTM, Euro-TSA) è stato utilizzato per verificare, su piante di vite di cv Merlot, la capacità di indurre resistenza alle infezioni di peronospora sia in applicazioni fogliari che in fertirrigazione. Il prodotto ha mostrato un’efficacia media del 35% nel controllare le infezioni di Plasmopara viticola con le applicazioni fogliari in tutte le fasi fenologiche testate, pur con un’ampia variabilità da prova a prova. Le applicazioni in fertirrigazione hanno avuto efficacia media del 25con una risposta più pronta nelle prime fasi di sviluppo della pianta che è andata via via scomparendo con la maturazione. Il fertilizzante testato ha offerto risultati interessanti che, anche non permettendo un suo uso esclusivo per la protezione dalla peronospora, forniscono utili informazioni per inserire il prodotto in strategie di lotta integrata al fine di supportare i tradizionali fungicidi, specialmente quelli di copertura ed in particolari fasi fenologiche., It is well known that resistance can be induced by physical, chemical, and micro-organisms (or their compounds and metabolites). Various fertilizer products enriched with amino acids, mineral elements or metals are also proposed as resistance inducers, often in combination with fungicides. A mineral organic fertilizer containing glucose, oligosaccharide and reducing sugars (ActiclasterTM, Euro-TSA) was used to verify on grapevine cv Merlot the ability to induce resistance to downy mildew infections either by foliar application or irrigation. The tested product showed an average efficacy of 35% by foliar applications across all the phonological stages tested, but with an high variability. The average protection provided by irrigation treatment was lower, on average 25% with the same variability, but also with an higher efficacy in the first development stages of the host. The tested product provided interesting results because, even if it cannot provide a complete protection against Plasmopara viticola infections alone, it can successfully inserted in disease control strategies in order to help classical fungicides, in particular phenological phases.

Recently, a mechanistic model based on the life cycle of Botrytis cinerea was developed. This model considers weather conditions, vine growth stages and the main infection pathways. In this study, the model was validated in nine epidemics observed from 2015 to 2017, in three locations in Italy. At maturity, no botrytis bunch rot symptoms were observed in vineyards; however, shelf-life assays showed the presence of latent infections in mature berries, with max 13% disease severity. The infection severity assessed after shelf-life assays was used to classify the epidemics as: severe, intermediate and mild (observed severity). Epidemics were classified in these three group also based on the model output (predicted severity). The model correctly evaluated the 89% of the epidemics. The severity of epidemics was also compared to the control strategies adopted by grapevine growers; it was outlined that growers taken right decision in 33% of cases only. Therefore, the model could be used as a tool supporting decision-making for Botrytis bunch rot control; it predicts the infection risk during the main susceptible vine growth stages: i. flowering (BBCH 69); ii. pre- bunch closure (BBCH 77); iii. veraison (BBCH 83); iv. pre-harvest (BBCH < 89).

Fusicladium eriobotryae (Cav.) Sacc. is the causal agent of loquat scab, which is the main disease affecting loquat (Eriobotrya japonica Lindl.) in the Mediterranean basin. F. eriobotryae infects leaves, shoots and fruits; scabby fruits are unsuitable for the market, resulting in significant economic losses. To predict the infection of loquat fruits, a mechanistic, weather-driven, disease model has been developed. By simulating conidial infection processes following a rain event, the model estimates the percentage of conidia that successfully infected loquat fruits at the end of an infection period; input data are hourly values of air temperature, rainfall, relative humidity and leaf wetness. The model is mainly derived from equations developed from recent in vitro and plant experimental results. Three data sets have been used to validate the model: (1) percentage of affected fruit in an unsprayed loquat orchard during two growing seasons (2011 and 2012); (2) infection occurrence in an unsprayed loquat orchard during 2013; and (3) expert appreciation of disease level on seven loquat growing seasons (expert elicitation). Results from this validation showed that the model is able to predict the infection periods and the development of the disease. The model could be used to improve the timing of fungicide sprays, thus reducing the number of applications.

Black rot is a fungal disease of grapevine that, in the last few years, has had a recrudescence in some areas. The knowledge on the life cycle of Guignardia bidwellii was retrieved through a systematic literature review and used to draw a mechanistic model able to simulate the fungus life cycle as influenced by weather and grapevine phenology. A meta-analysis was carried out on literature data to develop the mathematical equations describing the system both quantitatively and dynamically. Due to the lack of sufficient information, assumptions were introduced derived from similar systems. The model was then evaluated for its ability to describe the black rot epidemics in three representative cases. The model accurately represented the real system and has proven to be a useful tool for understanding the dynamics of epidemics. Further research will be necessary to acquire additional knowledge on some biological processes, to further validate the model and verify its use as a predictive tool for the disease

A new Decision Support System (DSS), named vite.net®, was recently developed for sustainable management of vineyards. The DSS is available in real-time on a web platform, accessible through personal username and password. The DSS is based on: i) a network of weather stations, ii) a server repository able to store weather data and site-specific information on cultural management (such as the list of treatments applied), iii) a set of mathematical models, that use the data collected in fields as input data to produce useful information about the tactical management of treatments and other cultural practices. After a pilot application in organic viticulture, the DSS was used on large scale by about 50 farmers and 50 technicians (both private and public) in different Italian grapevine growing areas, from Friuli to Sicily, on about 3,000 ha

A plant disease model is a simplification of a real pathosystem (i.e., the relationships between a pathogen, a host plant, and the environment) that determine whether and how an epidemic develops over time and / or space. Different approaches have been used for the development of plant disease models, with relevant improvements in recent years. Empirical models have been elaborated using data collected under variable field conditions since the second half of the last century. The so called 3 10 rules for predicting first seasonal infection of grape downy mildew is a precursor of this empirical approach for understanding relationships between pathogens, plants and the environment. By using this approach, the model is developed by searching mathematical or statistical relationships between field collected data and these relationships do not necessarily have cause-effect meaning. Lack of knowledge, accuracy and, especially, robustness are the main weaknesses of these models, which impose accurate validation and, usually, proper calibration when these models are used in different environments or under changing climate. Recent methods of data analysis, like for instance neural networks, improve the capability of searching the mathematical structure of the model but they do not overcome the above mentioned weaknesses. Mechanistic models are a new class of models based on knowledge of biological and epidemiological behaviour of the system under study. These models (also referred to as explanatory, theoretical, or fundamental) explain the pathosystem on the basis of what is known about how the system works in relation to the influencing variables. Mechanistic models are dynamic, because they analyse the changes over time of the components of an epidemic due to the external, influencing variables. Dynamic modelling is based on the assumption that the state of the pathosystem in every moment can be quantitatively characterised and that changes in the system can be described b

Wide scale monitoring, real time data analysis for decision support and use of prediction models are major tools in implementing IPM. Growers, who need to make proper decisions according to IPM principles and, at the same time, safeguard their income, require relevant information constantly and timely in order to make effective informed decisions. Current crop protection warning systems are mostly using regional scale weather and environmental data, but can only partially relate to local variability which is affected by microclimate, actual field level of pest infestation and disease severity, crop varieties, pesticide and agronomic treatments, etc. On the other hand, Decision Support Systems (DSSs) which consider more detailed local data are usually operated on a single grower level, and their local data is not or poorly used on a regional/multi- growers level. A substantial aspect in promoting current IPM practice should be combining and securely sharing both local and regional data in a simple and flexible manner, in order to improve analysis and informed decision making. The required tool is an accessible web based and real time combined system, which should allow holistic decision making with data and analytics up to a plot level, serving growers, agronomists, extension, academy and authorities for IPM practice and overall supervision. The IDeMCroP project is developing such a breakthrough combined platform, based on two innovative systems: Italian Vite.netTM for providing decision support through modelling and Israeli AgriTask for monitoring/scouting and data sharing. These field proven systems present complementary approaches in providing comprehensive real time information and prediction for decision making. Vite.netTM is a web-based DSS for crop protection in vineyards which analyses real time meteorological data from real and virtual weather stations, uses advanced modelling techniques and formulates decision support for controlling fungal diseases, such a

Tree crops production are highly dependent on external inputs, namely pesticides. Redesign tree crop production on other bases becomes a necessity. Before being tested in an experimental station or in real farm conditions, the global sustainability of these newly designed orchards needs to be evaluated. Adapted on the DEXiPM® model, the DEXiPM-pomefruit tool has been designed to make an ex ante assessment of the sustainability of innovative orchard systems. This model is based on a decision tree breaking the decisional problems of sustainability assessment into simpler units, referring to the economic,social and environmental dimensions of sustainability. In the frame of the PURE European project, we tested DEXIPM-pomefruit relevancy to assess the sustainability of innovative orchards. Two apple production systems were compared: one with exclusion netting against codling moth and one without. Exclusion netting is an innovative control method, which decreases the number of treatments by 30 % since all treatments against codling moth are suppressed. Moreover nets represent a good protection against yield loss risk due to climatic conditions (i.e. hail). However, its cost requires an important investment capacity. Assessed by DEXiPM-Pomefruit, the exclusion netting system globally ranked better than the uncovered system. Concerning the social aspect, the result was similar for both production systems. In contrast, economical performances were improved in orchards covered with nets, which are therefore protected against the climatic risk of yield loss. Moreover, the important decrease in pesticide use under nets contributed to improve all environmental impact indicators. DEXiPM-pomefruit helped selecting the most promising innovations in a given context. It was also used as a dashboard to determine strengths and weaknesses of the tested production systems and therefore to identify potential improvements

Powdery mildew, caused by Erysiphe necator (Schw.) Burr., is one of the most widespread and economically important diseases of grapevine. It is a policyclic disease, with primary, sexual infection cycles followed by several secondary, asexual cycles. The primary inoculum consists of ascospores produced in chasmothecia overwintered on the bark of vines, or of conidia produced by the mycelium present in dormant buds. Nonetheless, in many grape-growing areas, flag shoots (i.e. shoots generated by the infected, dormant buds) are usually absent in commercial vineyards. Chasmothecia form in late summer on the affected host tissue and, once mature, are dispersed by rain splashes to the bark of vines. In the following spring they repeatedly release ascospores that trigger new infection. The usual approach to powdery mildew control consists of repeated applications of fungicides from budburst to berries pea-size, and more; sanitation, i.e. the process that reduces or eliminates the initial inoculum from which the disease epidemic starts, would be highly effective in early-season control of powdery mildew. Efficacy of sanitation has been already evaluated in Northern Italy; interestingly, the application of a BioControl Agent based on Ampelomyces quisqualis Ces. (the biofungicide AQ10® WG) gave good results, comparable with those obtained with fungicides. This biofungicide applied twice, before and after harvest (i.e., during the formation and maturation of the chasmothecia) halved disease severity on bunches until the pea-sized berries stage in the following season. When sanitation with A. quisqualis was coupled with early-season (i.e., between bud break and fruit set) sulphur applications scheduled according to a weather-driven disease prediction model, disease severity on bunches was reduced by 98% (vs. an 80% reduction with sulphur sprays alone). Since this new strategy provided very promising results under experimental field conditions, it is being adopted under commerci

L’implementazione della produzione integrata come riferimento base per tutto il comparto agricolo, così come prevista dalla Direttiva europea sull’uso sostenibile dei pesticidi (2009/128/CE) che entrerà in vigore in gennaio 2014, comporta un complesso processo decisionale per i viticoltori, i quali dovranno usufruire di informazioni dettagliate ed aggiornate sulla situazione in vigneto, sul rischio di malattie e parassiti, sulle caratteristiche dei prodotti fitosanitari per la difesa e sulle loro limitazioni. Il sistema di supporto alle decisioni (in inglese Decision Support Sistem, DSS) vite.net®, sviluppato da Horta srl (www.horta-srl.com) nell’ambito del progetto Europeo MoDeM (www.modem-ivm.eu), ha l’obiettivo di aiutare i viticoltori nella gestione del vigneto. In particolare, vite.net® è basato su (i) una rete agrometeorologica, (ii) un server repository in grado di archiviare i dati e le previsioni meteo, le informazioni agronomiche ed operative (come il registro dei trattamenti) relative ad ogni specifico vigneto, (iii) un complesso di modelli matematici che utilizzano i dati raccolti per generare le informazioni utili per la gestione tattica dei trattamenti chimici. Vite.net® fornisce i dati meteorologici registrati con passo orario e quelli previsionali a 3 giorni sul punto geografico di ogni stazione, simula lo sviluppo della pianta, la dinamica delle infezioni primarie e secondarie di peronospora e mal bianco, la dose ottimale di fungicidi da di-stribuire in funzione del rischio di infezione, della fase di sviluppo della pianta e della copertura residua dei precedenti trattamenti. La combinazione di tutte queste informazioni consente agli operatori di intervenire al momento più opportuno, con il prodotto più adatto ed evitando sprechi e sovradosaggi. Vite.net®, dopo una fase dimostrativa in vigneti convenzionali e biologici, è oggi utilizzato com-mercialmente su circa 2800 ha nelle più vocate zone vitivinicole italiane

Grey mould caused by the fungus Botrytis cinerea is a common disease on several kinds of ripening fruits, including grape. In addition to quantitative losses, if strongly affected grapes are processed into wine the enzymatic activity of the fungus can have a negative effect on the wine quality. Epidemics are usually initiated in Spring from inoculum produced on different overwintering structures. Leaf infections and, with higher impact, floral infections can generate fruit infections through different infection pathways, some of which include a degree of symptomless latency. Not only environmental conditions but also bunch architecture and berry structure can influence disease severity and incidence: grape varieties with compact clusters are more susceptible to the disease. Traditionally, the control of B. cinerea in the vineyard is performed using synthetic fungicides: up to three applications per season, depending on the production line, the weather conditions and the risk a grower wants to take. Within the FP7-KBBE project "Pesticide Use-and-risk Reduction in European farming systems with Integrated Pest Management" (PURE) two different strategies were tested to reduce the use of synthetic fungicides against B. cinerea in viticulture: i) create a microclimate less favourable to the pathogen, and ii) use of Biological Control Agents (BCAs). The first strategy was tested at the Julius Kühn-Institute in Siebeldingen (Germany) in the grape growing seasons 2011 and 2012. Manual defoliation of the berry zone was performed before and after flowering to modify the bunch structure of compact varieties and at veraison to enhance ventilation of the berry zone during ripening. Defoliation was compared with one, two and three synthetic fungicides applications. In 2011, with high disease pressure, the defoliation at flowering was as effective as three botryticide treatments, while in 2012 disease pressure was too low to check differences between defoliation and fungicides. In

The transition from conventional to integrated pest management and, more in general, to integrated production requires an increase of knowledge about the vineyard system and includes also an increase of limits and fulfilments. The vineyard manager needs to be more and more informed and has to take several decisions for the proper management of the vineyard. Therefore, a web-based Decision Support System (DSS) was developed for guiding decision about tactical management of the integrated vineyard. The DSS is provided by Horta srl, a spin-off company of the University of Piacenza (www.horta-srl.com), and is available for registered users via the internet in an interactive way. It is composed by: (i) a network of weather stations that send real time data, (ii) a server repository that stores the weather data; (iii) an user interface that makes it possible to readily input vineyard-specific information and obtain supports for informed decision- making; (iv) a set of mathematical models that use weather data and vineyard-specific information to predict the epidemiology of the main grapevine fungal diseases and the plant development. Output provides information on: (i) current weather conditions and 3-day forecasts; (ii) the growth stage of the plants; (iii) information and decision supports for primary and secondary infections of Plasmopara viticola and Erysiphe necator, causal agent of grapevine downy and powdery mildew, respectively. In particular, two weather-driven, mechanistic, dynamic models are used to provide the following information for P. viticola: dynamic of the oospore population; occurrence of the main events for primary infections (oospores germination, zoospores release and dispersal, infection establishment and appearance of downy mildew lesions); infection severity and epidemic pressure of primary infections; fitness of the sporulating lesions and availability of the secondary inoculum; relative severity and epidemic pressure of secondary infections. Si

Maize is one of the principal crops grown destined to food and feed worldwide, after wheat and rice, with more than 600 million tons produced annually (FAO, 2003). Unfortunately, maize is susceptible to mycotoxin producing fungi as Aspergillus flavus, which can contaminate the ripening kernels with aflatoxins. Aflatoxin B1 is reported as the most toxic natural compound, causing chronic and acute toxicity on human and animal health. EU legal limits in raw maize are fixed at 5 µg/kg for products destined to humans and dairy animals and 20 µg/kg for other animal species (Commission Regulation 1181/2006, 165/2010 and Directive 100/2003). No mechanistic models for A. flavus–maize pathosystem are available in literature. In this work, the relational diagram of A. flavus infection cycle has been developed following the principles of “system analysis”; state variables, rates and driving variables were determined and linked in a coherent framework. Quantitative data for each steps of the cycle were collected from literature and mathematical equations were elaborated to connect driving variables to rates; an algorithm was also developed to finalize the model. The model predicts fungal development and toxin production (output) based on weather conditions (air temperature, relative humidity and rain). After a proper validation, the model may support stakeholders in order to: a) describe the dynamic of the contamination risk during the maize-growing season and at harvest, to rationalise harvest and post-harvest logistic; b) draw different scenarios based on real and simulated (climate change) meteorological data.

E’ stato messo a punto un sistema di supporto alle decisioni (Decision Support System, DSS) per la difesa dalla peronospora in viticoltura biologica. Il sistema è disponibile in tempo reale su piattaforma web, mediante un accesso tramite username e password. Vitebio.netTM è basato su (i) una rete agrometeorologica, (ii) un server repository in grado di archiviare i dati meteo e le informazioni agronomiche ed operative (come il registro dei trattamenti) relative ad ogni specifico vigneto, (iii) un complesso di diversi modelli matematici che utilizzano i dati raccolti per generare le informazioni utili per la gestione tattica dei trattamenti antiperonosporici. Vitebio.netTM fornisce i dati meteorologici registrati con passo orario e quelli previsionali a 3 giorni sul punto geografico di ogni stazione, simula lo sviluppo fenologico della pianta, la dinamica delle infezioni primarie e secondarie di peronospora e la dose ottimale di rame metallo da distribuire in funzione del rischio di infezione, della fase di sviluppo della pianta e della copertura residua dei precedenti trattamenti. Vitebio.net è in fase dimostrativa: vigneti biologici localizzati in aziende pilota di diverse aree vitivinicole italiane vengono gestiti secondo le informazioni generate dal DSS e confrontati con la pratica agricola aziendale, Vitebio.netTM is a DSS (Decision Support System) for guiding decision about tactical management of downy mildew in organic vineyards. The DSS is available for registered users via the internet in an interactive way. It is composed by (i) a network of weather stations that measure environmental variables, (ii) a server repository that stores weather data and fungicide application schedule; (iii) a set of mathematical models that use weather data and vineyard-specific information to predict the biological events relevant for decision making. Vitebio.net output provides information on both actual hourly weather conditions and 3-days forecasts, while its models simulate the risk for primary and secondary infections of Plasmopara viticola, and the optimum dose of copper to be applied depending on disease risk, residual coverage of the previous fungicide application, and grapevine growth and development. Several pilot farms are managing each year different vineyards following Vitebio.net and the results obtained are compared with the usual grower’s practice in order to evaluate the DSS performances.

I cleistoteci sono la forma prevalente di svernamento di Erysiphe necator in varie aree viticole. Le ascospore rilasciate dai cleistoteci causano le infezioni primarie ed avviano le epidemie oidiche. Attualmente, la protezione dal mal bianco è basata sull’uso ripetuto di fungicidi nel corso della stagione vegetativa. La possibilità di inserire interventi estintivi (diretti contro l’inoculo primario) nelle strategie di controllo è stata valutata attraverso prove di campo. In vigneti con alta dose di inoculo, vari fungicidi di sintesi applicati in post vendemmia ed un agente di biocontrollo a base di Ampelomyces quisqualis (AQ10) applicato in pre e post vendemmia hanno ridotto la gravità delle infezioni sui grappoli fino alla fase di grano di pepe nella stagione successiva alla loro applicazione, con una efficacia media del 59%. Nelle prove in cui i trattamenti estintivi sono stati abbinati ai trattamenti primaverili, i fungicidi di sintesi, A. quisqualis ed un olio minerale (Polithiol) applicato prima del germogliamento hanno ridotto la gravità di malattia sui grappoli, con una efficacia del 98%; il solo impiego primaverile di zolfo ha avuto un’efficacia dell’80%. I trattamenti estintivi con AQ10 e/o con olio minerale abbinati all’uso primaverile dello zolfo hanno aumentato in modo significativo l’efficacia di protezione dei grappoli rispetto al solo uso dello zolfo., ROLE OF SANITATION IN CONTROLLING GRAPEVINE POWDERY MILDEW Erysiphe necator, the causal agent of grapevine powdery mildew, overwinters, in many grapevine growing regions, as chasmothecia, which, in the following spring, discharge ascospores that cause primary infections and trigger powdery mildew epidemics. The disease is currently controlled with repeated applications of synthetic fungicides and sulphur during the grapevine growing season. The possibility to include sanitation treatments (against the overwintering primary inoculum) control strategies was evaluated. In vineyards with a high dose of primary inoculum different synthetic fungicides applied after harvest and a Biocontrol agent based on Ampelomyces quisqualis (AQ10) applied before and after harvest (i.e., during the formation and maturation of the chasmothecia), decreased disease severity on bunches until pea-sized berries stage in the following season, with an average efficacy of 59%. In the trials were sanitation treatments were coupled with early season treatments, synthetic fungicides, A quisqualis and a mineral oil (Polithiol) applied before bud burst, reduced disease severity on bunches by 98%; early season treatments with only sulphur showed an average efficacy of 80%. Sanitation treatments with AQ10 and/or mineral oil coupled with early season treatments with sulphur significantly increased the disease control efficacy of bunches, as compared to the sole use of sulphur.

MYCORED is a 7° FP large collaborative project funded by EC aimed at developing strategic solutions to reduce mycotoxin contamination in economically important food and feed chains. Wheat and maize are important crops considered in the project due to relevance for human and animal consumption and since causing major mycotoxin safety concerns worldwide. In particular, deoxynivalnol (DON) and zearalenone (ZEA) are secondary metabolites associated to Fusarium head blight (FHB), a wheat ear disease caused by a complex of Fusaria. Fumonisins (FUM) and aflatoxins (AFs), whose main producers are respectively F. verticillioides and Aspergillus flavus, are crucial problems in maize. A specific work package in MYCORED is aimed to develop and validate predictive models for these relevant fungi to forecast the risk of mycotoxin contamination in different geographic areas and years mainly based on meteorological conditions. A rational approach was elaborated and adopted by all countries involved (Italy, United Kingdom, Hungary, Russia, Egypt, Mexico, Nigeria, Argentina) in order to collect samples and data useful for models validation. Specific protocols were developed for crop sampling at harvest, proper questionnaires were prepared to collect cropping system data and suitable stations were selected for meteorological data. A proper data base was prepared and data storage is ongoing. A web access to predictive models is under development. Based on the first 2-year data (2009-2010), FHB model validation gave encouraging results, with good predictions in all the countries involved. More efforts are requested regarding maize, because the contribute of meteorological data seems not sufficient for a reliable prediction of FUM and AFs contamination at harvest.

L’oidio è una delle più diffuse malattie fungine della vite. L’approfondimento della conoscenza del ciclo biologico dell’agente causale, Erisyphe necator, è di estrema importanza per la gestione delle emergenze fitosanitarie. Numerosi modelli che descrivono parti del ciclo vitale del patogeno sono stati sviluppati da studiosi di tutto il mondo, ma ad oggi non è ancora stato proposto un modello che consideri il ciclo nella sua totale integrità. Dall’interesse di colmare tale mancanza è stato sviluppato un modello generale sul ciclo biologico di Erisyphe necator.

Epidemics caused by Plasmopara viticola on grapevines are caused by both primary and secondary infections that overlap for a part of the season. To date, this complexity has not been incorporated into models for grape downy mildew. A conceptual model was developed that links the quantitative aspects of both sexual and asexual stages of the P. viticola life cycle in a biologically coherent framework. Vanderplank’s logistic equation was integrated with a time step of 1 day; the resulting rates of disease increase were separately calculated for primary and secondary infections and linked together. Key model parameters included oospore density and development, infection efficiency for primary infections, ability of the lesions to reproduce asexually, infection efficiency for secondary infections, and carrying capacity of the host leaves. The model structural adequacy procedures (MSA) were used to estimate model parameters, and the model outputs were compared with real data not used in model development and parameterization. Real data were taken from published studies of 23 vineyards, where lesions had been previously genetically analyzed and distinguished as primary (caused by singleton genotypes) and secondary (caused by clonal genotypes). The 23 vineyards had experienced epidemics characterised by a low to high level of clonality. The estimated model parameters were biologically plausible and consistent with previous knowledge, and the model accurately mimicked the variability of the 23 real epidemics. The model represents a coherent mathematical structure for developing a simulator for downy mildew epidemics in the vineyard.

A dynamic model for Plasmopara viticola primary infections was evaluated by comparing model predictions with disease onset in: i) 100 vineyards of Northern, Southern and Insular Italy (1995 to 2007); ii) 42 groups of potted grapevine plants exposed to inoculum (2006 to 2008). The model simulates the development of any oospore cohort during the primary inoculum season, including: oospore germination; production and survival of sporangia; release, survival and dispersal of zoospores; infection and incubation. The model showed high sensitivity, specificity, and accuracy both in vineyards and in potted plants. The true positive and negative proportions were TPP=0.99 and TNP=0.87, respectively. Because of a certain proportion of false positive predictions (FPP=0.13), confidence in prediction of non-infections was higher than in prediction of infections. These wrong predictions occurred in early season or when the oosporic inoculum was low, or were triggered by isolated weak rain events. In only one case (a group of potted plants) there was infection when infection was not predicted (FNP=0.005). Considering that: i) the data used for evaluation were not used in model development, ii) the grape-growing areas considered represent the different climatic zones of grape cultivation in Italy, iii) both early and late primary infections were observed in the vineyards, iv) both first seasonal and further infections were observed in the potted plants, v) neither calibration nor empirical adjustment of model parameters were necessary, the model can be considered an accurate and robust predictor of P. viticola oosporic infections.

The purpose of the Prassis project (acronym of Pest risk assessment in the European Community: inventory of data sources) is to review and to produce an inventory of international and national key information and data sources, necessary to conduct the risk assessment of harmful organisms. A protocol was developed for inventorying the sources available in literature, in web-sites, in databases, and in software, in a structured, transparent, and efficient manner. The protocol was designed in such a way that the data sources inventoried could also be useful for future risk assessments in other fields and / or connected with other databases. About 250 descriptors (metadata) were defined for describing the data sources. Metadata for evaluation of data quality (strengths and weaknesses), accessibility for EFSA, and suitability for pest risk assessment were also included. International standards and codes were used whenever possible. The protocol was implemented in a userfriendly web-portal. The web-portal was designed to facilitate on-line entry of new data sources and on-line modification or updating of the existing ones. The web-portal also makes it possible to search the data sources within the inventory by using both basic and advanced search procedures, and to summarize results in a clear and concise way. A database was developed containing international and national information and data sources. The inventory covers the 27 European Member States and 34 third Countries. About 500 sources were entered in the web-based portal; because some sources contain information on different aspects of pest risk analysis, there are more than 600 records of interest. The project has three main weaknesses: i) although very large, the database is incomplete; ii) procedures for evaluating the quality of the sources included in the inventory can be improved; iii) the practical use of web-portal functionalities has not been thoroughly tested. Possible solutions are provided. 1

The main objectives of the Mopest project (acronym of Models for pest‟s epidemiology: review, documentation, and evaluation for Pest Risk Analysis) were to carry out a review and to produce an inventory of the models describing the establishment, development, and / or spread of plant pests on crops in Europe. This inventory should support the EFSA Panel on Plant Health in providing independent scientific advice on the risk of the spread, establishment, or development of organisms (plant pests) harmful to plants, plant products, or biodiversity; therefore, the inventory considers those models that can be potentially used for accurate and robust quantitative prediction of pest risk through the use of variables related to climate and / or plant growth and development as input factors. A protocol was developed for reviewing literature sources describing models relevant to the Mopest project. This protocol includes: i) a search strategy for retrieving information sources; and ii) a series of descriptors (metadata) that describe each source. The search strategy was developed according to the principles of the “systematic literature review”. About 200 metadata were defined for describing each model included in the inventory; international standards and codes were used whenever possible. The protocol was implemented in a user-friendly web-portal. The web-portal was designed to facilitate the on-line entry of new models and the on-line modification or updating of the existing ones. The web-portal also makes it possible to search the models within the inventory by using both basic and advanced search procedures, and to summarize results in a clear and concise way. A database was developed containing models related to wheat pests and quarantine pests for Europe as listed in the EPPO A1 list. About 200 models were entered in the web-based portal.

Initially plant disease models were developed as simple rules, graphs, or tables, and later as descriptive tools. Advances in environmental monitoring, automatic data processing, and botanical epidemiology enabled the development of a new class of mechanistic dynamic models, which are more accurate and robust. They explain mathematically the relations within a pathosystem (including both pathogens and host plants) by means of linked differential equations, and describe the way in which the system changes over time and space as an effect of external variables. Thus, the equation parameters do not have fixed values but vary according to the influencing weather conditions. These models require input data, particularly meteorological data, to be collected over time and space. Scales of time and space for inputs may differ according to the application of the model: from warning services, which use models to produce crop protection information at the collective level on a territorial scale, to precision agriculture which uses models at a within-plot scale. While the use of mechanistic dynamic models in warning services for crop protection is well established, their use in precision agriculture has yet to be developed. These models could be used to draw dynamic maps of current and future spatial distribution of both visible and latent infections within a plot, so that timing, active ingredients and rates of fungicides may be defined accordingly. The main challenge that needs to be overcome before this can be accomplished is the lack of meteorological inputs at the within-plot level.

Ascospores of Erysiphe necator are a relevant source of inoculum for spring infections. They form within chasmothecia (formerly named cleistothecia) which develop on the affected grapevine tissue in late summer to autumn, disperse to the bark by rain-splashes, and overwinter. Naturally dispersed chasmothecia were collected at 15-day intervals from ripening to complete leaf fall, in 2005 and 2006. Chasmothecia were placed on the bark of trunk pieces, overwintered outside, and observed weekly for the developmental stage and for discharged ascospores until the end of June. During leaf fall, 56% of chasmothecia had mature ascospores, 26% had immature ascospores, while 18% were unfilled (undifferentiated or empty). During winter (complete leaf fall to bud break) the distribution of chasmothecia in the three classes was 12%, 34%, and 28%, respectively, while after bud break it was 3%, 30%, and 67%, respectively. 35% of ascospores were discharged before complete leaf fall, 7% during winter (especially soon after leaf fall), and 58% after bud break. 55% of the total ascospores discharged before complete leaf fall were released from the earliest group of chasmothecia collected, 38% and 4% from the following groups, while no ascospores were discharged from the latest chasmothecia. These result showed that in northern Italy the development of chasmothecia depends on the period of their formation, resulting in two distinct periods of ascospore discharge in autumn and spring, as previously observed in Australia but not found in the state of New York. These findings may be relevant to disease epidemiology and management.

The Agricultural Production and Externalities Simulator (APES) is a modular simulation model system for estimating the biophysical behaviour of agricultural production systems in response to the interaction of weather, soil and agro-technical management options (APES, 2008). APES has been developed to allow the incorporation of other components which might be needed in order to simulate processes not yet included in the current version. Among these processes, plant diseases are interesting candidates because of their effects on crop yield and because of the implications as agro-chemicals use. A Diseases software component is currently under development adopting the design summarized by Donatelli and Rizzoli (2008). It aims at estimating the impacts of plant disease epidemics on plant growth and yield. It consists of four modules providing a generic frame to simulate disease development: 1) Disease progress, 2) Inoculum pressure (initial conditions), 3) Impacts on plants, and 4) Agricultural management impact on pathogen populations. The Disease progress module, developed as a generic model framework to simulate the epidemics caused by fungal pathogens, is briefly described herein

A 5-year study (2002-2006) was carried out in two pear orchards in northern Italy, by trapping air-borne ascospores of Venturia pirina. Characteristics of 155 ascospore discharge events (hour of the day, duration, ascospore number) and weather conditions of the hours preceding the beginning of the discharge (WD, wetness duration; R, rainfall; Tw, temperature during wetness) were analysed with the aim of better defining environmental conditions favouring ascospore discharge. Ascospore discharge showed a diurnal periodicity, with the 92% of total spores trapped in daylight. Thirty-seven percent of ascospore discharge events were triggered by rainfall, 55% by leaf wetness, while 8% occurred under dry conditions. The probability of ascospore discharge to occur was calculated using a logistic regression procedure with a stepwise selection of the independent variables. The variable ‘WD × Tw’ was selected as the most influential, while Tw, WD and R were not. The logistic equation provides the probability of an ascospore discharge to occur based on the combination of wetness duration and average temperature during the wet period preceding the beginning of the ascospore discharge. Probability was higher than 0.5 when ‘WD × Tw’ was higher than 197.5°C×h, while it was 0.9 when ‘WD × Tw’ was 585°C×h. This result showed that ascospore discharge in V. pirina is mainly influenced by wetness and temperature, while in V. inaequalis it depends mainly on rainfall. Calculation of the infection periods for controlling pear scab should take account of this difference.

Primary infections of Plasmopara viticola are caused by zoospores originating from oospores that overwinter in leaf litter or in soil. The inoculum is carried from the ground to the grape leaves by splashing rain, but little information exists about the relationships between rainfall, travelling distance and distribution of the inoculum within grapevine canopies. Experimentally, the soil of single curtain-trained plants was uniformly covered with a powder of two colours: red, under the projection of the canopy on the ground (row); blue, outside this projection (inter-row), in order to mark the splashes from raindrops that fell in these areas. Twelve traps for splashes were placed within the canopy at 3 different heights (40, 80, and 120 cm above the ground) to mimic leaves. Blotting papers were arranged in the abaxial part of the traps, substituted after each rainfall and observed for the number and dimension of the droplets. More than 23,000 droplets were collected (average of 3.9% of the trapping surface covered). The numbers of red and blue droplets were not significantly different, but the former were 1.6 times bigger than the latter. More than 99% of the total droplets were collected at 40 cm above the soil. Rain events lasted 2 to 19 hours, with 1.6 to 64.2 mm of water, 1.3 to 3.8 m/s of wind (max gusts of 30.6 m/s), but these differences did not influence droplets number and distribution significantly. Continuation of these studies will contribute to better understand the relationships between rainfall and primary inoculum of grapevine downy mildew.

Recent works showed that Stemphylium vesicarium, the causal agent of brown spot of pear, is able to colonize the herb plants of the lawn covering the orchard soil in a permanent manner. The fungus growths on the dead leaves of these plants as saprophyte and produces conidia from spring to autumn, and pseudothecia and ascospores of Pleospora allii from autumn to spring, more abundantly than on the pear leaf litter. Considering that S. vesicarium does not produce spores on the affected pear tissue, the orchard floor (pear leaf residues and dead herb plants) is then the inoculum source for both ascospores and conidia all season long. Recent works have then evaluated the possibility of reducing disease incidence by sanitation. The application of Trichoderma-based products on the orchard floor significantly reduces production of both ascospores and conidia as well as disease incidence on pear fruit. Use of Trichoderma opens new perspectives for controlling brown spot of pear, in addition to fungicide sprays to increase their efficacy when the disease pressure is high and in organic farming.

Pseudothecia in the leaf litter and the saprophytic colonization of the lawn plants, are the sources for Pleospora allii [Stemphylium vesicarium] ascospores and Stemphylium vesicarium conidia causing the brown spot of pear. Experiments were conducted in Italy from 2005 to 2007 to determine the efficacy of the leaf litter removal and the application of Trichoderma to the lawn to reduce the disease when applied alone or in combination with fungicide sprays. Fungicide sprays alone (7-8 applications per season) were not able to control the disease satisfactorily, but the methods for reducing the production of inoculum increased their efficacy. In 2005, combining fungicide sprays, leaf litter removal and Trichoderma reduced by 50% the disease incidence on fruits compared to fungicide sprays alone. In 2006 and 2007, leaf litter removal and Trichoderma were applied with no fungicides and showed an efficacy of 36 and 59%, respectively. Leaf litter removal was more effective than Trichoderma in 2005, when the latter was applied twice in early season (30 March and 18 April), while Trichoderma was more effective in 2007, when it was applied later and for three times (16 April, and 7 and 28 May). Trichoderma based products seem very promising for the reduction of S. vesicarium inoculum all season long.

Ascospores of Erysiphe necator are a relevant source of inoculum for spring infections. They form within chasmothecia (formerly named cleistothecia) which develop on the affected grapevine tissue in late summer to autumn, disperse to the bark by rain-splashes, and overwinter. Naturally dispersed chasmothecia were collected at 15-day intervals from ripening to complete leaf fall, in 2005 and 2006. Chasmothecia were placed on the bark of trunk pieces, overwintered outside, and observed weekly for the developmental stage and for discharged ascospores until the end of June. During leaf fall, 56% of chasmothecia had mature ascospores, 26% had immature ascospores, while 18% were unfilled (undifferentiated or empty). During winter (complete leaf fall to bud break) the distribution of chasmothecia in the three classes was 12%, 34%, and 28%, respectively, while after bud break it was 3%, 30%, and 67%, respectively. 35% of ascospores were discharged before complete leaf fall, 7% during winter (especially soon after leaf fall), and 58% after bud break. 55% of the total ascospores discharged before complete leaf fall were released from the earliest group of chasmothecia collected, 38% and 4% from the following groups, while no ascospores were discharged from the latest chasmothecia. These result showed that in northern Italy the development of chasmothecia depends on the period of their formation, resulting in two distinct periods of ascospore discharge in autumn and spring, as previously observed in Australia but not found in the state of New York. These findings may be relevant to disease epidemiology and management.

Initially plant disease models were developed as simple rules, graphs, or tables, and later as descriptive tools. Advances in environmental monitoring, automatic data processing, and botanical epidemiology enabled the development of a new class of mechanistic dynamic models, which are more accurate and robust. They explain mathematically the relations within a pathosystem (including both pathogens and host plants) by means of linked differential equations, and describe the way in which the system changes over time and space as an effect of external variables. Thus, the equation parameters do not have fixed values but vary according to the influencing weather conditions. These models require input data, particularly meteorological data, to be collected over time and space. Scales of time and space for inputs may differ according to the application of the model: from warning services, which use models to produce crop protection information at the collective level on a territorial scale, to precision agriculture which uses models at a within-plot scale. While the use of mechanistic dynamic models in warning services for crop protection is well established, their use in precision agriculture has yet to be developed. These models could be used to draw dynamic maps of current and future spatial distribution of both visible and latent infections within a plot, so that timing, active ingredients and rates of fungicides may be defined accordingly. The main challenge that needs to be overcome before this can be accomplished is the lack of meteorological inputs at the within-plot level.

In a temperature controlled glasshouse, seeds of tomato varieties not resistant to tracheo-fusarium diseases and rots were sown in soil inoculated with 3 strains of Fusarium oxysporum, F. solani, Pythium aphanidermatum, Pyrenochaeta lycopersici and Phytophthora nicotianae. In a 2nd experiment, seedlings were transplanted into similarly inoculated soil. Immediately after sowing/transplanting propamocarb 530 g/L +or- fosetyl 310 g/L at 4 or 3 mL/L was applied evenly to the soil surface. Damage from all the fungi except F. oxysporum f. sp. radici was insignificant in the sown tomatoes treated with propamocarb + fosetyl, while in the transplanted tomatoes, this treatment was effective except against F. solani and P. lycopersici.

The predictive models Rimpro and Ascab and the way they work are described. Both use weather data (temperature, relative humidity and rainfall) to predict the dispersal of ascospores. Experiments using them for scab control in Golden Delicious apples were conducted from 2001 to 2006. In normal years the models predicted less infection than the Mills tables but in years of severe infection the predictions were similar. Even so the new models led to fewer and more accurately chosen and timed treatments.

After discussing several existing models for predicting Peronospora spp. infection in vines, one more suited to Italian conditions and devised by the Catholic University of Piacenza and the plant health services of Emilia-Romagna and Piedmont and the University of Bologna is described. The model looks at the biological effect of weather conditions on the cycle of primary infection and is constructed on the basis of a flow diagram (illustrated), which takes account of the entire patho-system. It has been validated in various epidemiological conditions between 1995 and 2006 and has proved accurate with very few false alarms.