Submitted to: Entomology Society of America Pacific Branch Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/17/2004
Publication Date: 2/25/2005
Citation: Yokomi, R.K. 2005. Transmission profiles of California Citrus tristeza virus isolates by the cotton aphid, Aphis gossypii (homoptera: aphididae). Entomology Society of America Pacific Branch 89th Annual Meeting. p.103
Technical Abstract: Aphis gossypii is the principal vector of Citrus tristeza virus (CTV) in California. Based on host range, a population of A. gosspyii exists as the melon aphid (MA) or the cotton aphid (CA) biotype. Previous reports on CTV transmission used the MA reared on cucurbits. The objective of this study was to determine CTV transmissibility by the CA. The CA was collected near Sanger on cotton and reared on cotton. The MA was collected near Reedley on squash and reared on squash. In reciprocal host tests, the CA did not survive on squash while the MA did survive on cotton. CTV isolates from field infected citrus trees from plots in Tulare and Kern Counties were established in Madam Vinous (MV) seedlings in the greenhouse. Vector acquisition of CTV was conducted on young infected shoots of MV. Inoculation of CTV was conducted on young Mexican lime shoots using 5 to10 'viruliferous' aphids per plant. The CA transmitted the CTV isolates with a higher efficiency than did the MA. Using the CA, the CTV isolates fell into three transmission profiles: low (0 to 5%); intermediate (7% to 24%) and high (30% to 60%). Significantly more CTV isolates collected from a Kern Co. site had high transmission profiles than isolates collected from a Tulare Co. site.