Author
Yokomi, Raymond - Ray | |
JOOST, J - UNIV OF CA-RIVERSIDE | |
Backus, Elaine |
Submitted to: Conference of International Organization of Citrus Virologists
Publication Type: Abstract Only Publication Acceptance Date: 8/16/2004 Publication Date: 11/2/2004 Citation: Yokomi, R.K., Joost, J.H., Backus, E.A. 2004. Preliminary evaluation of two biotypes of aphis gossypii on the transmission of citrus tristeza virus. [Abstract] Conference of International Organization of Citrus Virologists. p.136. Interpretive Summary: INTERPERATIVE SUMMARY: Aphis gossypii is the primary vector of Citrus tristeza virus (CTV) in California and exists as two distinct biotypes: the melon aphid; and the cotton aphid. These biotypes are morphologically indistinguishable but have distinct host ranges. Both aphids have a wide host range outside of citrus and presumably feed and colonize citrus during the aphid's peak migration periods. Both A. gossypii biotypes were established in the laboratory and the host range, feeding behavior, and propensity for the transmission of CTV were examined. The melon aphid fed and developed on other hosts more than the cotton aphid. Preliminary analysis of probing behavior examined by direct current (DC) electrical penetration graph (EPG) monitoring on seedlings of the citrus cultivars Madam Vinous and Mexican lime indicated that the melon aphid probed more and ingested longer on both hosts than the cotton aphid. The melon aphid transmitted three of four CTV isolates with higher efficiency than the cotton aphid using Mexican lime as receptor plants. The role of the two biotypes of A. gossypii in relation to vector efficiency and epidemiology of CTV will be discussed. Technical Abstract: TECHNICAL ABSTRACT: Aphis gossypii is the primary vector of Citrus tristeza virus (CTV) in California and exists as two distinct biotypes: the melon aphid; and the cotton aphid. These biotypes are morphologically indistinguishable but have distinct host ranges. Both aphids have a wide host range outside of citrus and presumably feed and colonize citrus during the aphid's peak migration periods. Both A. gossypii biotypes were established in the laboratory and the host range, feeding behavior, and propensity for the transmission of CTV were examined. The melon aphid fed and developed on other hosts more than the cotton aphid. Preliminary analysis of probing behavior examined by direct current (DC) electrical penetration graph (EPG) monitoring on seedlings of the citrus cultivars Madam Vinous and Mexican lime indicated that the melon aphid probed more and ingested longer on both hosts than the cotton aphid. The melon aphid transmitted three of four CTV isolates with higher efficiency than the cotton aphid using Mexican lime as receptor plants. The role of the two biotypes of A. gossypii in relation to vector efficiency and epidemiology of CTV will be discussed. |