Abstract: 【Aim】 Morphological identification of Aleyrodes proletella(L.) is limited by small size, high degree of similarity to related species and polymorphism. This study aims to develop a technique based on mitochondrial DNA cytochrome c oxidase subunit I (mtDNA COI) gene sequence for the rapid identification of A. proletella, an invasive species newly found in mainland China. 【Methods】 The fragments of mtDNA COI gene of A. proletella and ten other whitefly species or cryptic species were amplified and sequenced using COI gene universal primers LCO-1490/HCO-2198. One pair of species-specific COI (SS-COI) primers, APZYJF and APZYJR, was designed. The target fragment amplified by the SS-COI primers (APZYJF/APZYJR) is 384 bp in length. The species specificity and sensitivity of the primer pair were tested. 【Results】 The species specificity of the primer pair was validated using ten other whitefly species and cryptic species, i.e., Trialeurodes vaporariorum (Westwood), Dialeurodes citri (Ashmead), Aleurodicus disperses (Russell), Paraleyrodes pseudonaranjae Martin, Bemisia afer (Priesner et Hosny), and five cryptic species of B. tabaci (Gennadius) (MED, Asia I, Asia II 1, Asia II 3 and China 1). All A. proletella specimens were successfully detected, and no cross reaction with other whitefly species or cryptic species was observed. The method was tested using individual male or female adult, individual 2nd instar, 3rd instar or red-eyed nymph, and even one grain of egg or single newly emerged 1st instar nymph, and proved to be applicable for all of these life stages. Sensitivity test results demonstrated that successful amplification could be obtained with the concentration of template DNA as low as 14.00±0.37 pg/μL, equal to 1/25 600 of a whole female adult of A. proletella. 【Conclusion】 The SS-COI method developed here provides a quick, simple and reliable molecular technique for the identification and monitoring of A. proletella, which would be useful in intercepting and blocking the further spreading of this new invasive whitefly species.

Key words: Aleyrodes proletella, cryptic species, SS-COI primers, rapid identification, molecular detection