Diterpenes-duvanes, cuticular

Cuticular diterpenes-duvanes and labdanes. Cutler have found that the cuticular diterpenes of green tobacco have both allelopathic and insect-deterrent effects (38). Present in the cuticle are duvane and/or labdane diterpenes (Figure 3) The levels of these specific cuticular components are believed to be responsible for the observed resistance of some types of tobacco to green peach aphids Myzus persicae (Sulzer), tobacco budworm Heliothis virescens (F.), and tobacco hornworm Manduca sexta (L.) (39). 

TI165 and TI 1396 produce duvane diterpenes and/or labdane diterpenes and/or sucrose esters (See Figures 1 and 2 for structures and References 5,7 and 8 for capillary gas chromatograms). The tobacco introductions with simple trichomes, TI 1112,1-35, and those with nonsecreting glandular trichomes, TI 1024 and TI 1406, produce low levels of diterpenes and sucrose esters. The cuticular extracts of all N, tabacum plants studied, independent of trichome type, contained a series of aliphatic hydrocarbons... 

Izimitani Y, Yahara S, Nohara T (1990) Novel acyclic diterpene glycosides, capsianosides A - F and I - V from Capsicum plants. Chem Pharm Bull 38 1299-1307 Jackson DM, Severson RF, Johnson AW, Herzog GA (1986) Effect of cuticular duvane diterpenes from green tobacco leaves on tobacco budwotm (Lepidoptera Noctuidae) oviposition. J Chem Ecol 12 1349-1359... 

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