Virescens

Tenehrio molitor Hg/pupa Galleria melonella Hg/pupa Aedes aeg pt] ppm Musca domestica Hg/pupa Heliothis virescens, ppm... 

Galleria mellonella (L.)a Grapholitha molest a (Busck) Heliothis virescens (F.)... 

Cypermethrin H. virescens Field strains Altered NaCh Little metabolic... 

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... 

The other major mechanism of pyrethroid resistance found in some field strains of Heliothis virescens was enhanced detoxication due to a high rate of oxidative detoxication, mediated by a form of cytochrome P450 (McCaffery 1998). Some strains, such as PEG 87, which was subjected to a high level of field and laboratory selection, possessed both mechanisms. Other example of pyrethroid resistance due to enhanced detoxication may be found in the literature on pesticides. 

McCaffery, A.R., GladweU, R.T., and El-Nayir, H. et al. (1991). Mechanisms of resistance to pyrethroids in laboratory and field strains of Heliothis virescens. Southwestern Entomologist Supplement 15, 143-158. 

The role of the nervous system in pheromone biosynthesis in moths is not clearly understood. Christensen and co-workers [208-211] proposed that the neurotransmitter octopamine may be involved as an intermediate messenger during the stimulation of sex pheromone production in H. virescens. These workers suggested that octopamine was involved in the regulation of pheromone production and that PBAN s role lies in the stimulation of octopamine release at nerve endings. However, contradicting results concerning octopa-mine-stimulated pheromone production were reported in the same species as well as other moth species [163,172,212-214]. 

A series of interesting observations was made [32] while maintaining N. inermis in a laboratory aquarium fey some months in the presence of selected prey, mainly Haminoea virescens and Bulla gouldiana. 

Little green heron, Butorides virescens Apalachicola River, 0.1-0.5 FW 45... 

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... 

Sparks TC, Pavloff AM, Rose RL et al (1983) Temperature-toxicity relationships of pyrethroids on Heliothis virescens (F.) (Lepidoptera Noctuidae) and Anthonomus grandis grandis Boheman (Coleoptera Curculionidae). J Econ Entomol 76 243-246... 

In the general spectrum of host-parasite relationships, there is considerable parasite-induced host variability resulting in perturbed host physiology, biochemistry, and developmental behavior (8, 21, 22). There is a wide range of speculation that the parasite has the capacity to modulate or regulate host systems (8, 10, 23). It is clear that the C. sonorensis polydnavirus induces developmental arrest in H. virescens larva (18, 24,... 

Northern blot analyses indicate that sequences of the four repeated elements are present on transcripts expressed in H. virescens by 2 hpp (25). Steady-state RNA levels peak at 2-6 hpp and then decline over the next 8 days. These transcripts are not as abundant as the cysteine-rich transcripts but are still major viral expression products. 

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. 

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