Leaf Trichomes and Resistance of Lycopersicon hirsutum and L. esculentum to Spider Mites

Spider mite behavior was characterized on leaflets, varying in extent of expansion, from mite-resistant Lycopersicon hirsutum and mite-susceptible L. esculentum plants. Survival, mortality, avoidance, and fecundity of the mites were related to Type VI trichome density and/or other covariants of leaflet development. At equivalent Type VI densities L. hirsutum leaflets were more resistant than those of L. esculentum. Thus, differential density of the Type VI trichome did not account fully for the resistance of the L. hirsutum plants. Mite mortality was associated with the presence of the L. hirsutum Type VI trichome tips and mite avoidance was associated with other factors that covaried with L. hirsutum leaflet development and leaflet surface.