Molecular identification of the biotypeof whitefly (bemisia tabaci) inhabiting the eastern region of saudi arabia

Abstract

The whitefly Bemisia tabaci (Germ.) is a worldwide important insect pest and vector of plant viruses. Recently, the whitefly populations upsurges dramatically in Al-Ahsa region of Saudi Arabia due to the expansion in greenhouse cropping system and it causes severe economic damage to many vegetable crops in greenhouses. Proper classification of the whitefly that prevails in the area is a crucial step towards efficient management of the pest. The whitefly is highly polymorphic with extreme plasticity in key morphological characters that vary according to the host which makes the taxonomic identity of existing biotype is difficult and sometimes ambiguous. The specimens for this study were collected from nine different locations of the whitefly populations in Al-Ahsa region. The study was done on the basis of three molecular techniques namely: (1) PCR amplification and polymorphic analysis of restriction enzyme digestion of mitochondrial cytochrome oxidase I gene (mtCOI), (2) Cloning, sequencing and phylogenetic analysis of mitochondrial 16S rRNAgene and (3) Random Amplified Polymorphic DNA Polymerase Chain Reaction (RAPE) PCR) analysis. The results of these molecular techniques clearly indicated the dominance of B biotype of the whitefly on crops grown in greenhouses in Al-Ahsa region of Saudi Arabia.