The ability of citrus aphids to transmit citres teisteza virus in northern of Iran was studied using citrus unshiu, C. sinesis and C. Aurantifolia as donor and recipievt host species. Aphis citeicola, A. gossypii and Toxoptera aurantii were used in transmission trials. Forty adults of each aphid species , after 24-48 hours of acquisition access feeding were transferred on to healthy recipient species and allowed to feed on the latter . Recilpient plants were indexed for tristeza , at least twenty days after inoculation access period, using C. aurantifulia as indicator species. None of aphid species examined could transmit citrus tristeza virus from any other species.
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