Search

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.

In this paper, we discuss the application of extreme value theory in the context of stationary $��$-mixing sequences that belong to the Fr��chet domain of attraction. In particular, we propose a methodology to construct bias-corrected tail estimators. Our approach is based on the combination of two estimators for the extreme value index to cancel the bias. The resulting estimator is used to estimate an extreme quantile. In a simulation study, we outline the performance of our proposals that we compare to alternative estimators recently introduced in the literature. Also, we compute the asymptotic variance in specific examples when possible. Our methodology is applied to two datasets on finance and environment.