Design of technical management plans for integrated protection in arboriculture

Pest and disease problems in orchards are significant due to intense pest pressure, linked in particular to the demand for high visual quality in the produce and to the concomitant evolution of pests. Addressing these problems whilst remaining mindful of environmental conservation requires the development of technical protocols for integrated pest management. In this paper, we outline the various approaches to this design process: the definition of rules for crop management decisions, experimental design and model-assisted design. We then draw on completed and ongoing research to illustrate the various components of the design of technical management strategies. The first step involves analysing existing protection practices, which may raise questions regarding compliance with recommendations and the compatibility between ecological value and effectiveness. This is followed by the development of rules for crop management decisions, illustrated by techniques used in cultural control. The third component is the study of the effect on parasitism of practices such as tree management, irrigation, pruning and nitrogen fertilisation. The fourth is the assessment of the costs of technical systems and their impact on biodiversity, illustrated using different biological groups. The final component is the modelling of interacting populations, illustrated by the example of the links between peach trees and moniliosis under the influence of cultural practices. We conclude by highlighting areas for further development: manipulating tree architecture, understanding complex food webs, and taking the ‘landscape’ scale into account.