Effects of an Entomopathogenic Nematode and a Nuclear Polyhedrosis Virus on Emergence of Heliothis virescens (Lepidoptera: Noctuidae)

1995 ◽  
Vol 30 (2) ◽  
pp. 243-250 ◽  
Author(s):  
M. R. Bell
Keyword(s):  
Heliothis Virescens ◽  
Untreated Control ◽  
Helicoverpa Zea ◽  
Entomopathogenic Nematode ◽  
Adult Emergence ◽  
Similar Rate ◽  
Tobacco Budworm ◽  
Whitening Agent ◽  
Nuclear Polyhedrosis ◽  
Lepidoptera Noctuidae

Cage tests were conducted during the 1993 growing season to determine the effect of incorporating an entomopathogenic nematode (Steinernema riobravis) in soil under cotton on subsequent emergence of tobacco budworm, Heliothis virescens (L.). When soil under seedling cotton was treated with 240K nematodes per m2 on 13 May, the number of moths emerging in cages was reduced by an average of 66%, compared to the untreated control, for at least 21 days following application. When a similar rate was applied on soil under mature cotton on 12 July, the number of moths emerging in treated cages after developing as larvae on the plants was 57% less over a 39 d period compared to the untreated control. In another cage study, application of the nematodes on wild geranium, Geranium dissectum L., an early-season host of tobacco budworms and cotton bollworms, Helicoverpa zea (Boddie), reduced adult emergence by 36% compared to untreated areas, whereas a single application of baculovirus from the celery looper (600 billion polyhedra per ha) reduced the emergence by 56%. In this latter test, adult emergence was further reduced (73% less than control) when a whitening agent was added to the virus application. These studies indicate than an entomopathogenic nematode, and the use of a whitening agent with baculovirus, might be useful in tobacco budworm management programs.

INFLUENCE OF INSECTICIDES - CYTOPLASMIC POLYHEDROSIS VIRUS COMBINATIONS ON PUPAL WEIGHT AND FECUNDITY OF TOBACCO BUDWORM (LEPIDOPTERA: NOCTUIDAE)

1989 ◽  
Vol 24 (4) ◽  
pp. 539-544 ◽  
Author(s):  
Abdul K. Mohamed ◽  
Jen-Rong Yang ◽  
Fred R. S. Nelson
Keyword(s):  
Heliothis Virescens ◽  
Methyl Parathion ◽  
Adult Emergence ◽  
Tobacco Budworm ◽  
Pupal Weight ◽  
Egg Hatch ◽  
Cytoplasmic Polyhedrosis Virus ◽  
Polyhedrosis Virus ◽  
Control Adult ◽  
Lepidoptera Noctuidae

Laboratory studies were conducted to determine the response of healthy and cytoplasmic polyhedrosis virus (CPV) infected Heliothis virescens (F.) larvae to LD50 of methomyl and methyl parathion. Methomyl-CPV combination adversely affected pupal weight and fecundity of the female. The effect of this interaction was synergistic. Exposure of CPV infected larvae to LD50 of methomyl resulted in a mean female pupal weight of 243 mg and a fecundity of 382 per female moth. These values were significantly lower than those of all other treatments. In contrast methyl parathion-CPV combinations did not result in a significant reduction in pupal weight as compared to the control. Adult emergence and egg hatch were not affected.

Early Season Application of a Baculovirus for Area-Wide Management of Heliothis/Helicoverpa (Lepidoptera: Noctuidae): 1992 Field Trial

1994 ◽  
Vol 29 (2) ◽  
pp. 192-200 ◽  
Author(s):  
M. R. Bell ◽  
D. D. Hardee
Keyword(s):  
Heliothis Virescens ◽  
Helicoverpa Zea ◽  
Tobacco Budworm ◽  
Emergence Period ◽  
Early Season ◽  
Treated Area ◽  
Untreated Area ◽  
Weed Hosts ◽  
Lepidoptera Noctuidae ◽  
Growing Region

A 9.6-km diam area in the intensive cotton-growing region of the Mississippi Delta was treated with an entomopathogenic virus to determine the effect on populations of adult tobacco budworms, Heliothis virescens (F.), and bollworms, Helicoverpa zea (Boddie), emerging from early season weed hosts. Four aircraft were used to treat ≈ 7,106 ha during 24–28 April at a rate of 100 larval equivalents per ha. Emergence data from cages placed over treated and untreated areas indicated that virus treatments reduced tobacco budworm emergence by 80.6% and bollworm emergence by 46.2%. During the emergence period, tobacco budworm traps in the area surrounding the treated area averaged 11.4 moths per trap per night. Average trap capture per trap per night in the center (6.4 km diam) of the treated area was 6.4 moths, a reduction of 43.9% compared with the untreated area. Correspondingly, reduction in trap counts for bollworm in the center was 21% when compared with the untreated area.

Bionomics of the Fall Armyworm (Lepidoptera: Noctuidae) and Its Ectoparasitic Nematode, Noctuidonema guyanense, in South Georgia

1996 ◽  
Vol 31 (2) ◽  
pp. 209-217
Author(s):  
C. E. Rogers ◽  
O. G. Marti ◽  
L. D. Chandler ◽  
A. M. Simmons
Keyword(s):  
Spodoptera Frugiperda ◽  
Heliothis Virescens ◽  
Helicoverpa Zea ◽  
Fall Armyworm ◽  
Corn Earworm ◽  
Cotton Bollworm ◽  
Tobacco Budworm ◽  
Beet Armyworm ◽  
South Georgia ◽  
Lepidoptera Noctuidae

The fall armyworm, Spodoptera frugiperda (J. E. Smith), is a perennial immigrant pest of several crops in south Georgia. Moths of S. frugiperda commonly are infested by an ectoparasitic nematode, Noctuidonema guyanense Remillet and Silvain in the Southeast. The seasonal chronology and natural association of these species are reported for Tift Co. from 1988 to 1994. Seasonal influxes of non-infested moths usually arrive in late April and dissipate in early November. Seasonal influxes of infested male moths follow the initial immigrants by 4 to 6 wks and disappear in the fall from 1 to 2 mos earlier than the general moth populations. Feral male moths that are moderately worn and infested by N. guyanense weigh less than moderately worn, non-infested males. Noctuidonema guyanense infests moths of several species of noctuids, but it has not been found on the cotton bollworm/corn earworm [Helicoverpa zea (Boddie)], tobacco budworm [Heliothis virescens (Fab.)], or beet armyworm [S. exigua (Hubner)].

Tobacco Budworm, Heliothis virescens (Lepidoptera: Noctuidae): Larval Location and Mortality on Bacillus thuringiensis-Treated Cotton

1999 ◽  
Vol 34 (4) ◽  
pp. 426-434 ◽  
Author(s):  
J. L. Jyoti ◽  
S. Y. Young ◽  
D. T. Johnson ◽  
R. W. McNew
Keyword(s):  
Bacillus Thuringiensis ◽  
Leaf Area ◽  
Food Consumption ◽  
Heliothis Virescens ◽  
Untreated Control ◽  
Larval Mortality ◽  
Tobacco Budworm ◽  
Lepidoptera Noctuidae ◽  
Larval Movement

One-d-old Heliothis virescens (F.) larvae were placed on Bacillus thuringiensis var. kurstaki Berliner-treated cotton leaves and terminals in the laboratory. Larval movement, food consumption and mortality were examined at 3, 6, 12, 24 and 48 h. Untreated leaves had a greater percentage of larvae on their under side than on their upper side; this location was not influenced by treatment with B. thuringiensis. When B. thuringiensis was applied to cotton terminals, first instars moved from B. thuringiensis-treated meristems; this movement increased with an increase in rate. Bacillus thuringiensis treatment also resulted in increased movement of larvae from the leaves and terminals onto the inner cup surface, although this movement was significantly greater than the untreated control only during the first 12 h after treatment. The leaf area consumed decreased with an increase in B. thuringiensis rate, but was not significantly correlated with larval mortality.

scholarly journals Ecdysteroidogenesis in Heliothis virescens (Lepidoptera: Noctuidae): Recombinant Prothoracicotropic Hormone and Brain Extract Show Comparable Effects

2019 ◽  
Vol 19 (3) ◽  
Author(s):  
Marisa Nardiello ◽  
Rosanna Salvia ◽  
Andrea Scala ◽  
Carmen Scieuzo ◽  
Sabino Aurelio Bufo ◽  
...  
Keyword(s):  
Heliothis Virescens ◽  
Complex Mixture ◽  
Prothoracic Gland ◽  
Tobacco Budworm ◽  
Brain Extract ◽  
In Vitro Tests ◽  
Prothoracicotropic Hormone ◽  
Lepidoptera Noctuidae

Abstract Prothoracicotropic hormone (PTTH) is a neuropeptide that triggers a cascade of events within the prothoracic gland (PG) cells, leading to the activation of all the crucial enzymes involved in ecdysone biosynthesis, the main insect steroid hormone. Studies concerning ecdysteroidogenesis predicted PTTH action using brain extract (BE), consisting in a complex mixture in which some components positively or negatively interfere with PTTH-stimulated ecdysteroidogenesis. Consequently, the integration of these opposing factors in steroidogenic tissues leads to a complex secretory pattern. A recombinant form of prothoracicotropic hormone (rPTTH) from the tobacco budworm Heliothis virescens (F.) (Lepidoptera: Noctuidae) was expressed and purified to perform in vitro tests in a standard and repeatable manner. A characterization of rPTTH primary and secondary structures was performed. The ability of rPTTH and H. virescens BE to stimulate ecdysteroidogenesis was investigated on the third day of fifth larval stage. rPTTH activity was compared with the BE mixture by enzyme immunoassay and western blot, revealing that they equally stimulate the production of significant amount of ecdysone, through a transduction cascade that includes the TOR pathway, by the phosphorylation of 4E binding protein (4E-BP) and S6 kinase (S6K), the main targets of TOR protein. The results of these experiments suggest the importance of obtaining a functional pure hormone to perform further studies, not depending on the crude brain extract, composed by different elements and susceptible to different uncontrollable variables.

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