The presence of the western flower thrips Frankliniella occidentalis was detected for the first time in Egypt. This species was found on ornamental plants as well as weeds grown in the Giza region during two field surveys carried out in the flowering seasons (July/August) of 2005 and 2006. Out of the 34 plant species inspected, this thrips was recorded on 27 species. Antirrhinum majus harbored the highest number of the thrips. F. occidentalis was differentiated from the onion thrips Thrips tabaci, which was often encountered on the same plant. The differences between the two species were evident in the number of segments of adult antennae, the pronotum of the prothorax, the adult wings and the 8th abdominal tergite by analyzing mounted specimens. F. occidentalis was encountered on Ipomoea tricolor plants (Convolvulacae) with prominent signs of a virus infection, from which impatiens necrotic spot virus (INSV) was isolated. The isolate was maintained in a greenhouse on begonia as a virus source. The virus was sap transmitted to a small range of plants, which developed characteristic symptoms of INSV. Infection was confirmed in all inoculated plants by DAS-ELISA using specific antiserum. Out of the 34 species collected in the field, INSV was found on plants of at least 16 tested plant species. This is the first reported occurrence of INSV in Egypt. Insect transmission tests were carried out using nymphs and adults of either F. occidentalis, F.tritci or T. tabaci species. F. occidentalis proved to be the vector of the virus, while T. tabaci and F.tritici failed to transmit INSV.
n/a