Tobacco virescens

In some resistant strains, both types of resistance mechanism have been shown to operate against the same insecticide. Thus, the PEG87 strain of the tobacco bud worm (Heliothis virescens) is resistant to pyrethroids on account of both a highly active form of cytochrome P450 and an insensitive form of the sodium channel (Table 4.3 and McCaffery 1998). 

The continuing use of pyrethroids in agriculture has led to the emergence of resistant strains of pests. One of the best-studied examples is the tobacco budworm (Heliothis virescens), a very serious pest of cotton in the southern United States (McCaffery... 

Several species of lepidopterous larvae cause bollworm-type injury to bolls and squares throughout the tropics. They include the bollworm [Heliothis armigera (Hbn.)], the tobacco budworm [Heliothis virescens (F.)], the black bollworm (Pro-denia latisfascia Wlk.), and in Peru Mescinia peruella Schaus. 

Cuts from the silica gel column were incorporated into artificial diets optimized for several economically-important agricultural pest insects, the pink bollworm Pectinophora gossypiella> the tobacco budworm Heliothis virescens> the corn earworm H. zea and the fall armyworm Spodoptera frugiperda. > Monitoring with this artificial diet bioassay, further column chromatography and preparative TLC on silica gel in diethylether-petrol yielded five... 

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). 

Hedin, P.A. et al.. Multiple factors in cotton contributing to resistance to the tobacco budworm Heliothis virescens F., in Plant Resistance to Insects, Heden, P.A., Ed., American Chemical Society, Washington, 1983, 347. 

The effects of selected fatty acid (Cio-Cia) methyl esters on the pink bollworm (Pectinophora qossypiella). bollworm (Heliothis zea) and tobacco budworm (Heliothis virescens) were determined, and a number of cyclopropyl, olefinic and acetylenic methyl esters were also tested (115). Methyl (Z,Z)-deca-2,8-diene-4,6-diynoate (matricaria ester) was lethal at low concentrations to all three insects. This last ester was isolated from Conyza canadensis but is found in vegetative matter of many plants of the Asteraceae. 

Multiple Factors in Cotton Contributing to Resistance to the Tobacco Budworm, Heliothis virescens F. 

C. nigriceps could distinguish between the odor of plants that have been damaged by its specihc host H. virescens and the odor of plants damaged by a closely related non-host. In a natural, non-agricultural environment, Kessler and Baldwin (2001) supplemented the odor of wild tobacco plants with synthetic volatiles and found that (Z)-3-hexenol, linalool and (Z)-a-bergamotene all increased the predation rate... 

Jaspamide (17), previously mentioned in Section 17.3, is a modified peptide isolated from a Jaspis sponge. Jaspamide shows insecticidal activity against Heliothis virescens with an LCS0 of 4 ppm, as compared to 1 ppm for azadirachtin. Jaspamide (17), showed more than 72% mortality at 100 ppm to both southern com rootworm and tobacco budworm. Iso-domoic acids A (40), B, and C are novel amino acids from the red alga Chondria armata. They... 

The macrolide halichondramide (3)62 showed more than 75% mortality (100 ppm) against newly hatched larvae of the southern com rootworm, Diabrotica undecimpunctata howardi, and the tobacco budworm, Heliothis virescens.44 The dimeric macrolides swinholide A and... 

Z)-9-tetradecenal (with (Z)-11-hexadecenal) [53939-27-8] CH3CH2CH2CH2CH=CH(CH2)7CHO tobacco budworm, Heliothis virescens... 

Berg B. G., Galizia C. G., Brandt R. and Mustaparta H. (2002) Digital atlases of the antennal lobe in two species of tobacco budworm moths, the Oriental Helicoverpa assulta (male) and the American Heliothis virescens (male and female). J. Comp. 

Berg B. G., Almaas T. J., Bjaalie J. G. and Mustaparta H. (1998) The macroglomerular complex of the antennal lobe in the tobacco budworm moth Heliothis virescens specified subdivision in four compartments according to information about biologically significant compounds. J. Comp. Physiol. A 183(6), 669-682. 

Rostelien T., Borg-Karlson A. K., Faldt J., Jacobsson U. and Mustaparta H. (2000a) The plant sesquiterpene germacrene D specifically activates a major type of antennal receptor neuron of the tobacco budworm moth Heliothis virescens. Chem. Senses 25(2), 141-148. 

With the introduction of the carbamate insecticides in 1956, resistance to carbaryl appeared between 1963 and 1966 in an orchard leafroller in New Zealand, in the cotton leafworm (Spodoptera) of Egypt, and in Heliothis virescens (the so-called tobacco bud-worm) on American cotton (Table VI). Resistance developed to OP compounds had already given some cross-tolerance to carbamates... 

The sex attractant of the eastern spruce budworm, Choristoneura fumiferana, is (E)-ll-tetradecenal (73). A probable precursor, (E)-ll-tetradecen-l-ol, is produced in the sex attractant gland (74), but this compound, which inhibits the male response to the aldehyde, does not appear to be released by the calling female. The (Z)-isomer of tetradecenal has been identified as one of the sex pheromones of the tobacco budworm, Heliothis virescens it is accompanied by (Z)-ll-hexadecenal (75, 76)7 Similarly, the female of the striped rice borer secretes two alkenals--(Z)-ll-hexadecenal and (Z)-13-octadecenal as its sex pheromone blend (77). 

A number of insect species, including corn earworm, Heliothis zea (Boddie), and tobacco budworm, Heliothis virescens (F.), contain and C,g aldehydes (C al and C al) in their pheromone blends (22, 23). The release rate of a C. al would be expected to be higher than that of a Cj al because of the molecular weight difference. A mixture containing 10% n-tetradecanal (CjA°al) in Z)-ll-hexadecenal [(J0-Il-Cj al] was formulated in four laminates, each made from a different type of polymeric membrane as the top and bottom layers vinyl, Mylar -coated vinyl, acrylic, and rigid vinyl film. (The saturated C,.°ol was used as a model because of availability.) The total alaehyde content was approximately 2.3 mg per cnr of laminate 0.7% (of the pheromone weight) of 2,6-di-tert-butyl-4-methylphenol (BHT) was added as an antioxidant. Table II gives the thickness of the polymers. 

Much interest has been shown in the biosynthesis of insect juvenile hormones (62 R1, R2 = Me or Et). In adult male moths, [l-14C]propionate was specifically incorporated into juvenile hormone I [JH-1, (62 R1 = R2 = Et)], and tracer was only found at, and equally distributed between, C-7 and C-ll.90 Application of [2-14C]-and [3-14C]-propionate led to extensive randomization of label, which suggests that C-2 and C-3 formed in propionate catabolism can be re-used as smaller fragments, whilst C-l is either removed from propionate in a metabolically active form or is highly diluted. Ternary complexes of brain, corpora cardiaca, and corpora allata from the tobacco budworm Heliothis virescens produced labelled JH-I and JH-II (62 R1 = Et, R2 = Me) when incubated with L-[Me-14C]methionine or sodium [l-l4C]propionate.91 Partial degradation of the juvenile hormones showed that in JH-I portions a and /3 (62) had incorporated one atom of tracer from each propionate, whereas fraction y was unlabelled, and in JH-II only fraction a was... 

Recent publications 0,4) in regard to the latter two plants indicate that they were also toxic to two bacteria which occur in the gut of the tobacco budworm Heliothis virescens (Fab.) and the corn earworm Heliothis zea (Boddie). The compounds, rhamnetin 3-0-glucoside and isoquercitrin, were isolated (3) from H camporum based upon their activity against Pseudomonas maltophilia and Enterobacter cloacae Also, a procyanidin was isolated (4) from Mj floribundum on the basis of activity against P. maltophilia. 

Carboxylesterases are responsible for the selective toxicity of malathion that favors mammals over insects. Carboxylesterase hydrolyzing trans-permethrin has been found in numerous insect species, including the fall armyworm, velvetbean caterpillar (Anticar-sia gemmatalis), cabbage looper (Trichoplnsia ni), tobacco budworm (Heliothis virescens), corn earworm (Helicoverpa zea), and spined soldier bug (Podisus maculwentris) (Yu, 1990). 

---