The Occurrence of Codling Moth in Low Latitude Countries: Validation of Pest Distribution Reports

Abstract

Phytosanitary restrictions are increasingly a factor in the ability of U.S. tree fruit exporters to gain and maintain access to worldwide markets. Under international trade rules, these restrictions must be based on specific guidelines, including an assessment of whether the proposed quarantine pest is likely to establish and spread under the climatic conditions of the importing country. Given the interest in and growth of temperate fruit production in the tropics, countries in the region (such as Taiwan, Columbia, Indonesia, and Thailand) have begun to impose a range of quarantine restrictions aimed at preventing the introduction of temperate zone pests. Apples (Malus ×domestica) are regulated in certain tropical/subtropical countries, such as Taiwan, for the presence of codling moth (CM; Cydia pomonella) in spite of reports in the literature that the distribution of CM is theoretically limited by daylength and chilling requirements to temperate regions. This work provides background as to why CM has been identified as a potential pest of quarantine concern in some low latitude countries; describes an approach used to validate worldwide CM distribution reports, providing additional information to allow for the revision of CM distribution maps; and demonstrates how accurate information regarding pest species distribution reports can aid in establishing an argument of ecological nonadaptability in the pest risk analysis process. Currently, a report of CM in Peru remains the only account of this pest's presence in low latitude countries that could not be refuted by the approach described here.