Refinement of the Pete Model for Prediction of Codling Moth Phenology in Walnuts

A preliminary conclusion of the research is that there does not appear to be significant genetic differences in developmental times between the codling moth populations in walnuts and apples. Codling moths were collected from walnuts and placed onto artificial diet as a rearing medium. Data obtained from these individuals were consistent with the data obtained from colonies of codling moth collected on apples. Similarly, codling moths which were successfully reared on walnuts did not demonstrate significant changes in developmental time. The number of larvae used in the trial was limited due to problems with rearing codling moth on walnuts in environmental growth chambers. Significant differences in diapause emergence curves did appear to exist for apple and walnut codling moth populations. Codling moth populations in apples appear to peak approximately 2 weeks prior to populations in walnuts. If this phenomenon remains consistent next season, then two diapuase emergence models will have to be constructed for codling moth.