Factsheet DSS pollen beetle Warwick model

Control with help of DSS Pollen Beetle Warwick model on platform.ipmdecisions.net. A series of development rate equations form the basis of the simulation model and are linked together in a program. The model simulates the development of cohorts of 500 individuals through spring emergence, egg laying and hatching, larval and pupal development and emergence, followed by dispersal of the new generation of adult beetles. For each stage, the percentage development is calculated each day by integrating the appropriate development rate curve. This percentage is accumulated over days until it reaches 100. At this point the individual moves to the next stage. Variability within the insect population is incorporated by assuming that, at any instant, the rates of development of a population held at a constant temperature are normally distributed (Phelps et al, 1993). The model uses soil temperatures or air temperatures depending on the stage of development. As multiple cohorts progress simultaneously, adult emergence/dispersal and egg laying can occur at the same time. DSS parameters The Pollen Beetle forecast requires hourly soil temperatures at a depth of approximately 6 cm and hourly air temperatures. This model requires historic data to provide risk forecasts. At present, suitable historic data is only available for a limited number of locations; please select ‘Edit This model predicts the timing of spring emergence of adult beetles, egg laying and then the emergence of a new (summer) generation of adults ready to disperse, followed by their dispersal. This enables users to undertake targeted monitoring and/or mitigating actions to reduce the risk of damage to the crop. The start date for the model is 1st February, as this is often the coldest period in the year. This DSS was adapted from work carried out in the UK. At present, suitable historic data is only available for a limited number of locations; please select ‘Edit Parameters’ and select the most appropriate location.