EFFICIENCY OF TEN POPULATIONS OF SCHIZAPHIS GRAMINUM (RONDANI) IN TRANSMISSION OF BARLEY YELLOW DWARF VIRUS-PAV (BYDV-PAV) IN IRAN

Variation in the transmission of barley yellow dwarf virus-pav (bydv-pav) by ten clones of an inefficient vecor species, shizaphis graminum (rondani) originating from different region of iran was evaluated in the present study. after acquiring the virus, aphids of each clone-virus isolate combination were caged on 30 seedling using three 4th instar nymph per seedling. the inoculated and control plants were assayed by elisa and visually to determine the rate of transmission as well as elisa value for each treatment. a positive correlation was found between the rate of transmission and absorbance value. aphid clones differed in their efficiency to transmit virus isolate. any single clone transmitted virus isolate with varying efficiencies. the aphid clone belonging to virus isolate origin transmitted virus isolate at highest rate. in general, shahre kord and shahreza clones of aphids showed highest and delijan and varamin clones exhibited lowest transmission efficiency among aphid clones.