Laboratory studies on the potential of three insect growth regulators for control of the tsetse fly, Glossina morsitans morsitans Westwood (Diptera: Glossinidae)

AbstractExperiments were carried out to determine the effects of the insect growth regulators (IGRs), diflubenzuron and two of its analogues, on adult female Glossina morsitans morsitans Westw. The most effective method of dosing was by topical application, and less pronounced effects followed tarsal contact with treated surfaces and contact during mating with treated males. The compounds had no effect on female length of life or the number of offspring produced, but following topical application at 0·5 μg/female or above, most offspring produced throughout reproductive life (more than 100 days) failed to pupariate. Little difference was detected between the effects of the three IGRs tested. Following the application of diflubenzuron to oviparous insects, egg hatch is inhibited; it is suggested that in the larviparous tsetse fly such compounds act by inhibiting the biosynthesis of chitin at the time of pupariation. IGRs show promise as potential agents for the control of Glossina in the field, and the quantities required would probably not exceed the quantities of insecticides used in current operations against tsetse flies.

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Sterilising effects of benzyl-l,3-benzodioxoles on the tsetse fly Glossina morsitans morsitans Westwood (Diptera: Glossinidae)

Bulletin of Entomological Research ◽

10.1017/s0007485300013651 ◽

1982 ◽

Vol 72 (3) ◽

pp. 473-481 ◽

Cited By ~ 14

Author(s):

P. A Langley ◽

M. A Trewern ◽

L. Jurd

Keyword(s):

Topical Application ◽

Glossina Morsitans Morsitans ◽

Mature Oocyte ◽

Tsetse Fly ◽

Glossina Morsitans ◽

Plant Materials ◽

Female Survival ◽

Low Solubility ◽

Blood Meals ◽

Contact Insecticides

AbstractThree benzyl-l,3-benzodioxoles and three benzylphenols were tested for their ability to sterilise Glossina morsitans morsitans Westw. following topical application in acetone. Two of the former compounds, 5-ethoxy-6- (4-methoxyphenylmethyl)-l,3-benzodioxole and 5-ethoxy-6-[l-(4-meth-oxyphenyl)ethyl]-l,3-benzodioxole, caused total sterility in females at a dose of 10 μg per fly, and remained effective even after one year's storage at 4°C. Dose-fecundity data indicate a reduction to 50% fecundity (ED50) was achieved with 2·5 μg of the former or 0·5 μg of the latter per fly. An ED90 of 8·5 μg and 2·5 μg, respectively, is indicated. The latter compound reduced the survival of treated females and males and surviving males were incapable of inseminating even though copulation appeared normal. The effects on female survival and fecundity, of feeding the compounds at 0·25 and 1·0% in blood, were variable, owing to their low solubility and variations in the size of blood-meals. The highest doses of the former compound led to ovarian atrophy in females, which can be described as an effect on fecundity. Lower doses induced sterility through egg death and atrophy after ovulation. The latter compound acted more rapidly than the former, preventing ovulation of the first mature oocyte in a higher proportion of flies. The activity of these compounds, which were derived by modification of plant materials, and are non-mutagenic, renders them likely candidates for evaluation as contact insecticides for Glossina in the field.

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Disruption of Glossina morsitans morsitans (Diptera: Glossinidae) eclosion behaviour: a novel method for evaluating the action of neurotoxic agents

Bulletin of Entomological Research ◽

10.1017/s0007485300042656 ◽

1992 ◽

Vol 82 (4) ◽

pp. 547-552 ◽

Cited By ~ 2

Author(s):

J. Ždárek ◽

D.L. Denlinger

Keyword(s):

Glossina Morsitans Morsitans ◽

Tsetse Fly ◽

Tsetse Flies ◽

Behavioural Pattern ◽

Glossina Morsitans ◽

The Central Nervous System ◽

Lethal Time ◽

Novel Method ◽

Sublethal Doses ◽

Peripheral Action

AbstractAs the tsetse fly, Glossina morsitans morsitans Westwood extricates itself from the puparium and moves upward through the soil the ptilinum expands and contracts rhythmically and thus generates a stereotypic behavioural pattern that persists for up to 10 h if the tsetse fly remains confined. The response, which is easily recorded tensometrically from the movements of the ptilinum, can be exploited as a tool for evaluating the behavioral response of tsetse flies to various neurotoxic agents. The behavioural assay proves useful in providing precise information about the latency of the response and lethal time, and can suggest likely modes of action. For example, sublethal doses of pyrethroids reversibly suppressed the contraction cycles, a response consistent with the peripheral action of this insecticide. In contrast, chlorinated hydrocarbons greatly increased contraction frequency, a result consistent with the action of these agents on the central nervous system (CNS). Assays utilizing eight commercial insecticide preparations (Pybuthrin, K-othrin, Vaztak, Reldan, Safrotin, Acetellic, DDVP, Antrix) demonstrate the utility of this method for detecting subtle perturbations of the CNS and neuromuscular system.

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Genetic relationships between subspecies of the tsetse fly Glossina morsitans inferred from variation in mitochondrial DNA sequences

Canadian Journal of Genetics and Cytology ◽

10.1139/g84-109 ◽

1984 ◽

Vol 26 (6) ◽

pp. 692-697 ◽

Cited By ~ 7

Author(s):

Martin Trick ◽

Gabriel A. Dover

Keyword(s):

Mitochondrial Dna ◽

Dna Sequences ◽

Dna Hybridization ◽

Genetic Relationships ◽

Glossina Morsitans Morsitans ◽

Tsetse Fly ◽

Tsetse Flies ◽

Glossina Morsitans ◽

Site Variation ◽

Local Restriction

A 750 base pair segment of DNA from the tsetse fly Glossina morsitans morsitans was isolated by means of molecular cloning. It was shown by DNA hybridization to have substantial sequence homology with a defined region of the mitochondrial genomes of several Drosophila species. When used as a probe against DNA prepared from single tsetse flies, the cloned sequence revealed local restriction site variation between members of the G. morsitans subspecies complex. This feature was used to demonstrate maternal inheritance of the sequence in progeny of hybrid crosses and to assemble comparative restriction maps for a 3-kilobase segment of each mitochondrial genome. The data obtained from these exercises point to a higher genetic identity between G. m. morsitans and G. m. centralis than between either form and G. m. submorsitans.Key words: mitochondrial DNA, tsetse fly species, Glossina morsitans.

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Studies on Trypanosoma (nannomonas) congolense: IV. Experimental immunization of mice against tsetse fly Challenge

Parasitology ◽

10.1017/s0031182000000585 ◽

1980 ◽

Vol 80 (1) ◽

pp. 133-137 ◽

Cited By ~ 17

Author(s):

V. M. Nantulya ◽

J. J. Doyle ◽

L. Jenni

Keyword(s):

Glossina Morsitans Morsitans ◽

Trypanosoma Congolense ◽

Tsetse Fly ◽

Uninfected Control ◽

Tsetse Flies ◽

Glossina Morsitans ◽

Variable Antigen ◽

Experimental Immunization

SummaryGroups of mice were exposed to multiple bites by tsetse flies (Glossina morsitans morsitans) infected with a clone of Trypanosoma congolense spread over a period of 8 days. The mice were subsequently treated with Berenil 10 days after the first fly bite as were uninfected control mice. The group of mice which received 12–15 infectious fly bites on two occasions, 21 days apart, were subsequently resistant to infection when re-challenged by flies infected with the same clone of T. congolense. These mice were also immune to challenge by flies infected with a different bloodstream variable antigen type derived from this same stock. The immunity was stock-specific and directed against the metacyclic forms of the parasite, but was short-lived.

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