Identification of Thrips palmi: Morphology Compared with Real-Time PCR
Vierbergen G, van den Beld HE, van de Vossenberg BTLH, Kox LFF
Plant Protection Service, P.O. Box 9102, 6700 HC Wageningen, The Netherlands.
Correspondence: g.vierbergen@minlnv.nl
In juvenile stages the EU IA1 quarantine organism Thrips palmi is increasingly more intercepted at port of entry in Europe. Because of the difficulties with identification of these stages notifications result in reference in higher taxonomic levels. In The Netherlands a real-time PCR assay is developed, which enables the identification to species levels of every stage. To test the sensitivity inserted eggs in leaf tissue were detected by amplification of the cut out plant tissue. Real-time PCR assay resulted in the detection of T. palmi eggs in 19 of 56 cut out tissues from ¡®naturally¡¯ infested imported eggplant-fruit. The assay does not have any influence of environmental factors affecting development of the thrips, no genetic variation is established (Knox LFF et al. 2005. OEPP/EPPO Bulletin 35:141¨C148). The method can be standardized and needs less extensive experience than morphological identification. Disadvantages are the longer analysis time, the strictly presented results, the sub-specificity and the higher costs. Quarantine laboratories asked for identification of T. palmi have to weigh the advantages and disadvantages of employing PCR or morphological expertise or both.
