Technical Abstract: Many Nicotiana species have glandular trichomes that produce complex chemical exudates, which consist primarily of diterpenes (duvanes and labdanes) and/or sugar esters (sucrose esters and glucose esters). These components have a variety of biological activities, including allelochemical effects on plants, microorganisms, and insects. Duvane diterpenes and sucrose esters from tobacco, N. tabacum, stimulate the ovipositional behavior of lepidopteran pests, Heliothis virescens (F) and Manduca sexta (L). Volatile components produced by Nicotiana species also affect orientation and alighting behavior of insects pests and beneficials. Diterpenes and sugar esters from several Nicotiana species are topically toxic to the tobacco aphid, Myzus nicotianae Blackman, the greenhouse whitefly, Trialeurodes vaporarium (Westwood), and the silverleaf whitefly, Bemisia argentifolii Bellows & Perring. These compounds also reduce growth hdevelopment of fungal and bacterial pathogens of tobacco and other crops. Because pests come in contact with exudates on the leaf surface of Nicotiana species, breeding lines with high levels of these components are being developed. The use of sugar esters as natural insecticides for control of soft bodied insects such as whiteflies and aphids is being pursued.