Aphid Resistance and Leaf Surface Chemistry of Sugar Ester Producing Tobaccos

Sugar ester producing tobacco lines were evaluated for aphid resistance and other surface chemicals. The cembrenoid and labdenoid diterpenes, α- and β-4,8,13-duvatrien-1-ols, α- and β-4,8,13-duvatriene-1,3-diols, (12Z)-labda-12,14-diene-8α-ol (cis-abienol), (13E)-labda-13-ene-8α,15-diol (labdenediol), docosanol, and sugar esters were quantified using high pressure liquid chromatography and compared with aphid infestation ratings. Regression analysis of aphid [Myzus persicae (Sulzer)] infestation rating and leaf surface chemistry was statistically significant and showed that surface chemicals were important in explaining the observed variation in the aphid infestation ratings. A significant negative correlation was found between aphid ratings and sugar ester levels among the 62 entries evaluated (r = −0.2758, P = 0.0301). α and β monols (α- and β-4,8,13-duvatrien-1-ols) were also significantly correlated with aphid infestations in this study (r = −0.2743, P = 0.0310 and r = −0.2797, P= 0.0109, respectively...