Morphological and Molecular Identification Protocols for Bactrocera dorsalis: A Joint Validation Study

Abstract

Bactrocera dorsalis is considered among the most destructive and economically important invasive fruit flies worldwide. Native to Southeast Asia, in just a few years, it has spread almost throughout all of sub-Saharan Africa, causing fruit loss in several commercially grown crops. In Europe, it is frequently intercepted as larva on imported fruits during phytosanitary inspections. In recent years, adult specimens have been caught in traps in Austria, Italy, and France, increasing the level of attention to this species. Rapid and unambiguous identification by European plant health laboratories is important to effectively prevent its introduction and establishment in Europe. The harmonized use of validated diagnostic protocols is essential. However, in entomology, unlike other disciplines, diagnostic protocols often lack validation data to support their suitability as adequate identification tools. In this study, tests from two international diagnostic protocols for the identification of B. dorsalis underwent a thorough validation process to assess their performance characteristics (analytical and diagnostic sensitivity, specificity, accuracy, repeatability, and reproducibility). A novel process of a joint validation of morphological and molecular identification protocols is reported. The novelty of this approach arises from the fact that morphological and molecular tests are validated in the same study, based on the same panel of samples, also allowing a two-way control on the assigned values of samples. Potential critical issues that could represent weaknesses of the protocols are also discussed in detail. [Figure: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Keywords

• Bactrocera dorsalis
• morphological and molecular identification
• oriental fruit fly
• performance characteristics
• plant health
• Tephritidae