Tobacco horn worm

The effect of caffeine has been tested with insect herbivores. Tobacco horn-worms, Manduca sexta, die from a diet with 0.3% caffeine, and the beetle Calioso-bruchus chincnsis becomes sterile at a concentration of 1.5% (Nathanson, 1984). However, experiments showed that caffeine does not protect the coffee plant against the leaf miner Perileucoptera coffedla, one of the major pests of coffee (Filho and Mazzafera, 2000). 

Few attempts have been made to characterize insect glucosyl-transferases and the reports that do exist are quite equivocal. Thus, in contrast to mammalian glucosyltransferases that are localized in the microsomal fraction of tissue homogenates ( ), those from the housefly, cockroach (Periplaneta americana) and locust (S ch istocerca can ce11 ata) are reported to be associated with the 15,0D0-2O,OOOg pellet (13,14) and that from the tobacco horn-worm (Manduca Sexta) with TRe igh speed supernatant (14). The enzyme has been identified in gut and fat body tissues oT the few insect species studied and may have a fairly broad tissue distribution. 

Zimoch L, Merzendorfer H. Immunolocalization of chitin synthase in the tobacco horn-worm. Cell Tissue Res. 2002, 308, 287-297. 

Petuniolide C (XVIII) was available in reasonable amounts, and we submitted samples of the compound elsewhere for tests upon other insects. The tobacco horn-worm (M. sexto) was susceptible to this compound in artificial diets (as might have been expected from early observations of larvae on the plant), with only 50% survival of animals to the prepupal stage at a dosage of 20 ppm (J. Oliver, personal communication). Another caterpillar, the variegated cutworm (Peridroma saucia Hubner), was... 

Nicotine (43) inhibits radicle growth in Lepidium and is toxic to Lemna (Wink, 1993). It is a useful insecticide and probably serves as a defensive compound in the plant (Wink, 1993). Some coadapted insects, such as the tobacco horn-worm, Manduca sexta, are highly resistant to the effects of... 

Bekkouche K, DeraU Y, Cherkaoui S, Veuthey JL, Christen P (2001) CaJystegine distribution in some solanaceous species. Phytochemistry 58 455 462 Bentz JA, Barbosa P (1992) Effects of dietary nicotine and partial starvation of tobacco horn-worm, Manduca sexta, on the siuvival and development of the parasitoid Cotesia congregata. Entomol Exp Appl 65 241-245... 

Weissenberg M, Levy A, Svoboda JA, Ishaaya I (1998) The effect of some Solanum steroidal alkaloids and glycoalkaloids on larvae of the red flour beetle, Tribolium castaneum, and the tobacco horn worm, Manduca sexta. Phytochemistry 47 203-209 Weyerstahl P, Christiansen C, MarschaU H (1992) Isolation and synthesis of isohumbertiol, the first naturally occurring sesquiterpene alcohol with a humbertiane skeleton. Liebigs Ann Chem 1325-1328... 

Several saturated C32, C33, and C34 hydrocarbons with methyl branches in the Cl 1 -13 positions have been identified from the tobacco horn-worm (Heliothis virescens) (Lepidoptera Noctuidae) that elicit a hostseeking response of its parasitoid, Cardiochiles nigriceps. These kairo-mones have been synthesized by Vinson et ai (170) using appropriate methyl ketones and Wittig reagents followed by catalytic reduction. 

Leaves with large holes. Causes Horn-worms other caterpillars. Hornworms are y -4Vi" caterpillars with white diagonal stripes. The tobacco hornworm has a red horn projecting from the rear, while the tomato horn-worm fias a black horn. Handpick or spray plants with BTK to control them. Do not spray eaterpillars that are covered with small white cocoons these cases eontain the larvae of parasitic wasps that are natural hornworm predators. 

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