DNA barcoding and population genetic structure of the red palm weevil, Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in Egypt based on mtDNA sequencing

The red palm weevil (RPW), Rhynchophorus ferrugineus, is the most damaging and invasive pest of palm trees worldwide. This pest is native of Southeast Asia and Melanesia and has extended its invasion into the Middle East, Africa, Mediterranean region, Caribbean, Northern America and Australia. An explicit knowledge and understanding of RPW diversity is critical for devising a management strategy of this pest species. In this study, we compared the DNA sequences of the mitochondrial cytochrome c oxidase sub-unit I (COI) gene from RPW populations collected from different regions of Egypt to identify the recent RPW genetic structure and to monitor the invasion history of this economically ruined pest. The comparison of DNA barcodes of 88 adult individuals sampled from 12 different locations, revealed the identification of three different haplotypes. Analysis of RPW population structure revealed a low fixation index (FST) value and a negative, statistically significant Tajima’s D value, with raggedness indices of zero for all locations, except Assiut and Fayoum. The results of molecular variance and phylogenetic analyses showed no genetic diversity among RPW populations and this genetic resemblance reflects a single and strong gene pool suggesting no evidence of invasive species or gene flow from overseas.