Bull. Spec. CORESTA Congress, Jerez de la Frontera, 1992, p. 144, P4, ISSN.0525-6240
The cuticular chemistry of aphid resistant tobaccos
USDA-ARS, Athens, GA, USA
Most Nicotiana tabacum types have multicellular glanded trichomes which produce chemical secretions containing diterpenes and/or sugar esters. Our work indicates that these components affect tobacco aphids, Myzus nicotianae Blackman, in several ways, including selection of plants by alate (winged) migrant aphids, and the survival and fecundity of apterous (wingless) aphids. Typically the trichomes of aphid susceptible tobaccos produced alpha-and beta-4, 8,13-duvatriene-1,3-diols. Aphid resistant lines either have nonsecreting trichomes and very low levels of cuticular components or glanded trichomes which produce exudates consisting of alpha- and beta-4,8,13-duvatriene-1-ols, and/or cis-abienol, and/or sucrose esters (6-O-acetyl-2,3,4-tri-0-acyl-sucrose). The effect of specific cuticular isolates on the survival of adult aphids will be discussed.