Trichomes chemical resistance

We have been involved in mechanistic studies aimed at understanding the basis of glandular trichome-based insect resistance in wild Solarium (potato) and Lycopersicon (tomato) species. Much effort has focused on identification of wild members of the Solanaceae with potentially useful resistance traits for introgression into Solarium tuberosum and Lycopersicon esculentum. In many cases resistance has been shown to be conferred by glandular trichomes, modified epidermal cells (i) which function as physical and/or chemical barriers against insect attack (2-10 > Tingey, this volume). 

Stipanovic, R. D. 1983, Function and chemistry of plant trichomes and glands in insect resistance protective chemicals in play epidermal glands and appendages, pp. 69-100. In P. A. 

Srivastava R, Sachdev K, Madhusudanan KP, Kulshreshtha DK (1991) Structure of pescaproside E, a fatty acid glycoside from Ipomoea pescaprae. Carbohydr Res 212 169-176 Steffens JC, Walters DS (1991) Biochemiceil aspects of glanduleu trichome-mediated insect resistance in the Solanaceae. ACS Symposium Ser voL 449, Americtm Chemical Society, Washington, DC, pp 136-149... 

Most Nicotiana species have multicellular, glanded leaf trichomes which may produce chemical secretions containing diterpenes and/or sugar esters with C2 to C,o acyl moieties. These components affect tobacco aphids, Myzus nicotianae Blackman, in several ways, including influencing the acceptance or rejection of plants for colonization by alate migrant aphids, and the survival and fecundity of alate and apterous aphids. Cuticular diterpenes and sucrose esters were isolated from the cuticular extracts of aphid resistant and susceptible N. tabacum genotypes. These compounds were applied topically to the backs of apterous aphids. 

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