Benoit Jeannequin

Compatibility among entomopathogenic hyphocreales and two beneficial insects used to control Trialeurodes vaporariorum (Hemiptera: Aleurodidae) in Mediterranean greenhouses

The effect of the combined use of Encarsia formosa or Macrolophus caliginosus and one of three marketed mycoinsecticides, Mycotal® (Leucanicillium muscarium-based), Naturalis-L™ (Beauveria bassiana-based) and PreFeRal® (Isaria fumosorosea-based), on the control of the whitefly, Trialeurodes vaporariorum, was studied under laboratory and greenhouse conditions. The results of both types of tests, the bioassays and the greenhouse trials, for all combinations of E. Formosa with each of the three mycoinsecticides showed that the total mortality of larval populations of T. vaporariorum was not affected. The mortality of T. vaporariorum larvae treated in the second instar revealed the capacity for both B. bassiana- and L. muscarium-based formulations and E. formosa to kill the host either separately or in association. Because of its higher pathogenic activity (under our test conditions), L. muscarium provoked a large proportion of mycoses in larvae exposed to parasitization. In contrast, the efficacy of parasitization was higher in larvae treated with B. bassiana and exposed to E. formosa because of a lower pathogenic activity of the fungus. Bioassays carried out with third-instar larvae of T. vaporariorum showed a low susceptibility to both tested fungi. Consequently, mortalities recorded in larvae subjected to the combined treatments by consecutive exposures or at 2-4 days post-parasitization were mainly caused by the development of the parasitoid. Greenhouse trials showed that fungus-induced mortality of T. vaporariorum in plants treated with L. muscarium, I. fumosorosea, and B. Bassiana was significant compare to control. L. muscarium, B. bassiana and I. fumosorosea killed young whitefly larvae and limited parasitization to 10% or less. Second-instar larvae of M. caliginosus were not susceptible to L. muscarium and B. bassiana formulations with any mode of contamination: direct spraying of larvae, spraying on the foliar substrate or by contaminated T. vaporariorum prey. In greenhouse trials, M. caliginosus populations treated with fungi were not significantly affected compared to controls.

EU27 and USA leadership in fruit and vegetable research: a bibliometric study from 2000 to 2009

We performed an analysis of published literature related to fruit and vegetable and indexed in the Web of Science®, covering the period 2000–2009. The EU27 and the USA are the two leading actors in terms of number of fruit and vegetable articles published. This paper compares their publication outputs using bibliometric methods. We assessed the fruit and vegetable species, topics (from Web of Science® categories), countries and institutions involved. The top species, topics and institutions are ranked according to their number of publications. Collaboration networks between countries were mapped to visualize the intensity of the relationships involved in international fruit and vegetable research and to obtain an overall picture of the fruit and vegetable research landscape. These results can be useful for policy makers.

SERRISTE: Daily Greenhouse Climate Set-Point Determination for Tomatoes

Abstract SERRISTE is a decision support system providing suitable climatic setpoints for the production of greenhouse tomatoes. The system is based on an analysis of the practices as they can be defined by expert growers and agronomists, and expressed as a set of constraints. The most significant ones links the day and night temperatures to the forecasted solar radiation, to balance the rates of growth and development with that of the photosynthesis. Additional physical knowledge is used to determine the necessary set-points from the goal mean temperatures. SERRISTE has been tested in southern and western France in extension services and has proven its capability to ensure a good if not better production at a lower cost.

Analysis of knowledge involved in greenhouse climate management - Application to the determination of daily setpoints for a tomato crop

Abstract In the framework of a project aiming at the design and implementation of a decision making system for daily management of a greenhouse tomato production, the fundamental heuristic knowledge used in the determination of climatic setpoints is identified and articulated. This analysis pertains to modern greenhouses located in Mediterranean France and to winter productions of tomatoes. Since no comprehensive quantitative models of the crop and greenhouse systems are yet sufficiently developed for automated decision making purpose the underlying motivation behind this work is to come out with an adequate body of heuristic knowledge that can then be represented and used within an artificial intelligence approach. A key feature and novel aspect of the presented decision model stems from its integration of short term (three days) weather predictions that are worth considering in the southern France context in order to reduce the stress caused to plants by abrupt and important changes of weather. The exploitation for climate management purpose of the property that tomato plants act as efficient temperature integrators over a several day period (i.e. plants have “reservoir” capabilities) is considered. Chiefly, by enabling anticipatory decisions the intelligent use of predictions together with “reservoir” capabilities can potentially contribute in a significant manner to energy saving.