Heliothis virescens larvae diets

Table IV. Growth-Inhibitory Activity of Some Bioactive Constituents Derived from Geranium viscosissimum var. viscosissimum Fed in an Artificial Diet to First-Instar Larvae of Heliothis virescens...

Oil Limonoids Fed in an Artificial Diet to Flrst-Instar Larvae of Heliothis virescens... 

Derivatized Tetranortriterpenoids from Azadirachta indica and Melia azedarach Fed in Artificial Diet to FirsMnstar Larvae of Heliothis virescens. 

Homeosoma electellum) contain high concentrations of tra-chyloban-19-oic acid (70) and ( —)-16-kauren-19-oic acid (71) in their florets. As sunflower florets that contain only small amounts of these compounds are a major portion of the diet of first instar larvae of this insect, it is likely that these acids serve as feeding inhibitors. At the 1% level, both kaurenoic and trachylobanoic acids decreased the growth of sunflower moth larvae and tobacco budworm (Heliothis virescens) by about 50%. At the 0.5% level, both reduced larval growth of the cotton bollworm and the pink bollworm to less than 5% (Fig. 22.23) (Mabry and Gill, 1979). The Z-and -isomers of (- )-ozic acid (72) have been isolated from Helianthus occidentalis and may be associated with resistance to insect attack (Stipanovic et al., 1979). 

Differential insecticidal activity for a-terthienyl in different herbivorous lepidoptera has been noted. Under fluorescent daylight tubes, the topical LD50 values for the tobacco hornworm Manduca sexta, the tobacco budworm Heliothis virescens, and the European corn borer Ostrinia nubilalis were in the ratios 1 47 70 (755). The toxicokinetics of tritiated a-terthienyl were studied in these three insects. Following either oral or topical administration, larvae of 77. virescens and O. nubilalis rapidly cleared the chemical from the body via the feces, but M. sexta did more slowly. For example, after 48 h of feeding on treated diet, the ratio of radiolabel in the body to that in feces was 16 84 for O. nubilalis, 32 68 for 77. virescens, and 58 42 for M. sexta. Likewise, the half-time values for elimination of after topical application in O. nubilalis, 77. virescens, and M. sexta were approximately in the ratios 1 3 6. Unfortunately,... 

---