Phenology modelling of major insect pests in fruit orchards from biological basics to decision support: the forecasting tool SOPRA

The forecasting tool SOPRA has been developed with the objective of optimizing timing of monitoring, management and control measures of insect pests in fruit orchards in Switzerland. Applying time-varying distributed delay approaches, phenology-models were developed driven by solar radiation, air temperature and soil temperature on hourly basis. Relationships between temperature and stage-specific development rates for relevant stages of the life cycles were established under controlled laboratory conditions for Dysaphis plantaginea, Hoplocampa testudinea, Cydia pomonella, Grapholita lobarzewskii, Cacopsylla pyri, Rhagoletis cerasi, Anthonomus pomorum and Adoxophyes orana. The implementation of body temperatures in the models is based on habitat selection and biophysical modelling of habitat conditions. In order to validate modelling, phenology predictions were compared with several years of independent field observations. On the basis of local weather data, the age structure of the pest populations is simulated and crucial events for management activities are announced. Through a web interface, the simulation results are made available to consultants and growers ( http://www.sopra.info) and the latter can be applied as a decision support system for the eight major insect pests of fruit orchards in the alpine valleys and north of the Alps on local and regional scale.