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The AOPN tomatoes and cucumbers carries the DEPHY Serre project with the objective of zero pesticides for these two major vegetables in a soilless system while maintaining economic and environmental performances. The realization of a survey at the start of the project, performed in each production area, identified the mains pests encountered for these crops. Analytic experimentations occurred in two experimental stations, aiming to identify bioproducts of interest as an alternative to chemical pesticides. In parallel, the implementation of monitoring systems was set up among 5 pilot sites (3 for tomatoes and 2 for cucumbers). This stage aimed to validate the results obtained in the experimental stations and to perform a systemic approach by integrating several levers with a global strategy of crop protection. The conducted trials in the stations identified several biocontrol products against tomatoes botrytis (fungi, bacteria or antagonist yeast), and powdery mildew for both crops (drying products which have a direct action against the pathogen or products stimulating the plant defense system). On the pilot sites, the trials enabled to tune the global protection strategies set up in tomato crops with a focus against whiteflies by combining several technics: releasing periods of Macrolophus regarding the crop calendar, interest of feeding at the start of the season, interest of reduced deleafing in release areas, use of biocontrol products, yellow sticky traps for mass trapping, aspiration around the plant's head, etc., The AOPN tomatoes and cucumbers carries the DEPHY Serre project with the objective of zero pesticides for these two major vegetables in a soilless system while maintaining economic and environmental performances. The realization of a survey at the start of the project, performed in each production area, identified the mains pests encountered for these crops. Analytic experimentations occurred in two experimental stations, aiming to identify bioproducts of interest as an alternative to chemical pesticides. In parallel, the implementation of monitoring systems was set up among 5 pilot sites (3 for tomatoes and 2 for cucumbers). This stage aimed to validate the results obtained in the experimental stations and to perform a systemic approach by integrating several levers with a global strategy of crop protection. The conducted trials in the stations identified several biocontrol products against tomatoes botrytis (fungi, bacteria or antagonist yeast), and powdery mildew for both crops (drying products which have a direct [br/] action against the pathogen or products stimulating the plant defense system). On the pilot sites, the trials enabled to tune the global protection strategies set up in tomato crops with a focus against whiteflies by combining several technics: releasing periods of Macrolophus regarding the crop calendar, interest of feeding at the start of the season, interest of reduced deleafing in release areas, use of biocontrol products, yellow sticky traps for mass trapping, aspiration around the plant's head, etc.

Les distributions des valeurs extremes generalisees (GEV) et de Pareto generalisees (GPD) sont tres utilisees dans l’analyse des valeurs extremes en hydrologie. La calibration de ces distributions au-dela d’un seuil pose cependant un certain nombre de problemes et en particulier celui du biais dans les queues de distributions. Une methode est proposee pour quantifier ce biais, methode basee sur la calibration d’une fonction a variations lentes. Tenir compte de cette fonction permet entre autre d’obtenir des estimateurs de quantiles plus precis. Par ailleurs, il est necessaire de supposer que les observations proviennent d’une seule etmeme distribution. Cette hypothese est satisfaite a condition que l’on puisse garantir une influence faible des inondations et des modifications artificielles telles que les structures regularisant le courant, les reservoirs, les digues, ... Dans le cas contraire, l’analyse devra etre effectuee sur la base de donnees censurees, en se basant uniquement sur les observations non influencees par ces divers phenomenes physiques. Les distributions des points «non inondes» et des points «inondes» seront alors toutes deux necessaires. Nous presenterons une approche permettant d’apprehender ce type de probleme et nous illustrerons son efficacite sur des donnees reelles de debits horaires pour la riviere Molenbeek a Erpe-Mere (Belgique). paper print ispartof: Revue de Statistique Appliquée pages:5-31 status: published