Insects Heliothis virescens

Flubendiamide (54 ISO-proposed Nihon Nohyaku Co., Ltd./Bayer CropSdence) [125, 126,127] (Fig. 35.13) with a heptafluoro-isopropyl moiety in the anilide part of the molecule (Chapter 34) induces ryanodine-sensitive cytosoUc Ca + transients that were independent of extracellular Ca concentration in isolated neurons from the pest insect Heliothis virescens as well as in transfected CHO cells expressing the RyR from Drosophila mdanogaster. Binding studies on microsomal membranes from H. virescens flight muscle revealed that 54 interacts with a site distinct from the ryanodine binding site and disrupted the Ca + regulation of ryanodine binding by an allosteric mechanism. 

The generalist feeding insect Heliothis virescens, the tobacco budworm, has relatively high resistance to canavanine but not to a number of other nonprotein amino acids (Berge et al., 1986). In this case, canavanine (37) was shown to be neither excreted nor sequestered, but rather metabolized by the insect. In Caryedes brasiliensis, Sternechus tuberculatus... 

Lee SH, Soderlund DM (2001) The V410M mutation associated with pyrethroid resistance in Heliothis virescens reduces the pyrethroid sensitivity of house fly sodium channels expressed in Xenopus oocytes. Insect Biochem Mol Biol 31 19-29... 

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. 

Nicotine is rapidly excreted by three insect species that normally feed on Nicotiana tabacum (10,11). Manduca sexta. Trichoplusia ni, and Heliothis virescens eliminate the unchanged alkaloid after Ingestion, and no evidence was obtained to indicate that nicotine was subjected to any metabolic transformations. 

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. 

Krieger J., GanBle H., Raming K. and Breer H. (1993) Odorant binding proteins of Heliothis virescens. Insect Biochem. Molec. Biol. 23, 449 456. 

Boroczky, K., Park, K.C., Minard, R.D., Jones, T.H., Baker, T.C. and Tumlinson, J. H. (2008). Differences in cuticular lipid composition of the antennae of Heliocoverpa zea, Heliothis virescens, and Manduca sexta. J. Insect Physiol., 54, 1385-1391. 

Recent research has shown that the pheromone mediated behavior of lepidopterous insects is very complex. The chemical components of the pheromones are usually simple molecules, but complex mixtures involving permutations of geometry, functionality, and chain length are often required to elicit the complicated behavioral repertoire that eventually culminates in mating. To elucidate the chemical and behavioral aspects of this communications system, we have used a combination of methods including collection of the volatiles emitted by the female, analysis by high resolution capillary gas chromatography (GC), and the sequential and temporal analysis of the male s behavioral response to the pheromone blend and components thereof. New liquid phases and state of the art techniques have been developed for capillary GC to separate all the components of a pheromone blend. With these methods the chemical communication systems of Heliothis virescens (F.) and H. subflexa (Gn.) have been analyzed and certain aspects have been elucidated. 

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... 

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). 

Since commercial insecticides are frequently targeted to act on sodium-channels, the toxicity of pumiliotoxins on insects was studied [32]. PTX B (323A) proved to be more active than PTX 251D on Heliothis virescens (specially by contact), in agreement with the importance of the number of hydroxyl groups present. The low amount of PTX B present precluded the quantification of the effects. 

Construction of sex-linked genetic markers in major economic pests will facilitate expansion of genetic control methods such as the sterile insect technique and backcross sterility in Heliothis virescens. 

The lepidopteran genus Heliothis includes some species that are among the most important of all phytophagous insect pests. The Heliothis complex has worldwide distribution and is responsible for economic losses over a wide range of field and horticultural crops. In the USA, two species of these pests -- Heliothis zea (Boddie) otherwise known by the common names bollworm, com earworm, tomato fruitworm, etc. and the tobacco budworm, Heliothis virescens (F.)... 

The two Heliothis species that have most commonly developed resistance are Heliothis virescens and armigera. The loss of the organophosphorous insecticides (OP s) to resistance in the 1970 s literally pushed the synthetic pyrethroids into the marketplace. Since their introduction in 1978, it was clear that these highly cost effective and environmentally compatible insecticides would be heavily relied upon to replace the OP s. The synthetic pyrethroids have become the most widely used chemicals for the control of insect pests on cotton, representing about 48% of all the insecticides applied worldwide ( ). Most applications are directed toward controlling Heliothis spp. 

Lamberty M., Ades, S., Uttenweiler-Joseph, S., Brookhart, G., Bushey D., Hoffmann, J.A., Bulet, P. Insect immunity. Isolation from the lepidopteran Heliothis virescens of a novel insect defensin with potent antifungal activity. 

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