Entomology Commons^™

The Relationship Of Catalase Activity To The Trade-Off Between Reproduction And Lifespan In The Giant Waterbug, Belostoma Flumineum, Matthew R. Gilg

Masters Theses

Senescence is the process by which organisms age and ultimately die. Life history theory suggests that the allocation of energy into growth and reproduction is necessarily associated with a decrease in energy available for the maintenance of the soma. Many studies have shown that early or increased rates of reproduction are often correlated with a decrease in longevity, but few studies have investigated physiological correlates to this event. Catalase is an enzyme involved in the removal of oxygen free radicals implicated in damaging cellular components that contribute to senescence. A decrease in catalase activity with age could increase the organism's …

Sequential Sampling Plans For The Red Sunflower Seed Weevil (Coleoptera: Curculionidae) In Oilseed Sunflower, Chengwang Peng, Gary J. Brewer

Department of Entomology: Faculty Publications

Decision making on control of the red sunflower seed weevil, Smicronyx fulvus LeConte, requires a reliable and efficient method for classifying the pest population. The objective of this study was to develop sequential sampling plans for red sunflower seed weevil control in oilseed sunflower. Sequential classification sampling plans were developed from Wald's sequential probability ratio test (SPRT) by using a negative binomial distribution. Operating characteristic and average sample number functions were computed for a range of k values. Two sampling plans were developed for the economic thresholds of six and eight weevils per sunflower head, based on a k value …

Population Genetics And Gene Variation Of Stable Fly Populations (Diptera: Muscidae) In Nebraska, Allen L. Szalanski, David B. Taylor, Richard D. Peterson Ii

Department of Entomology: Faculty Publications

Genetic variation in stable fly, Stomoxys calcitrans (L.),populations from Nebraska, Canada, and Texas was sampled. Four of 12 allozyme loci were polymorphic, with an average of 1.7 alleles per locus. Observed and expected heterozygosities were 0.086 and 0.070,respectively. Nei's genetic distance between populations averaged 0.001 and ranged from 0.000 to 0.005. Wright's F statistics revealed greater variation within than among populations. Allele frequencies were homogeneous among temporal samples from a single population. Polymerasechain reaction—restriction fragment length polymorphism (PCR—RFLP) analysis of 6.4 kb of the mitochondrial DNA genome with 16 restriction enzymes revealed no variation in stable fly populations from Canada, …

Identification Of Screwworm Species By Polymerase Chain Reaction-Restriction Fragment Length Polymorphism, David B. Taylor, Allen L. Szalanski, Richard D. Peterson Ii

Department of Entomology: Faculty Publications

Restriction fragment length polymorphisms in polymerase chain reaction amplified fragments (PCR-RFLP) of mitochondrial DNA were used to differentiate species of New World screwworms (Diptera : Calliphoridae) . Twenty-seven restriction enzymes were screened on five regions of mtDNA . Eleven restriction fragment length patterns differentiated New World screwworm, Cochliomyia hominivorax (Coquerel), from secondary screwworm, Cochliomyia macellaria (F.) . Five restriction fragment length patterns were polymorphic in C. hominivorax while all fragment patterns were fixed in C. macellaria. Diagnostic restriction fragment length patterns were used for species diagnosis, whereas intraspecific variable patterns were used to characterize field samples and laboratory strains …

Ultrastructural Changes In The Milk Gland Of Tsetse Glossina Morsitans Centralis (Diptera; Glissinidae) Female Infected By A Dna Virus, Rosemary C. Sang, Walter G.Z.O. Jura, Leonard H. Otieno, Peter Ogaja

All Peer-Reviewed Publications

Milk glands, dissected out and collected from Glossina morsitans centralis (Machado) females, artificially inoculated at the third-instar larval stage with a virus suspension obtained from hypertrophied salivary glands of wild-caught virus-infected Glossina pallidipes (Austen), were processed for routine electron microscopy and examined for pathological changes. They were compared to milk glands dissected out from normal female G.m. centralis at the same stage of pregnancy cycle. Upon dissection there were notable physical differences between control and virus-infected milk glands. Histologically, some areas of the gland developed severe degeneration while other areas developed less severe pathological changes. Ultrastructural studies revealed the presence …

Functional Morphology And Anatomy Of The Polypneustic Lobes Of The Last Larval Instar Of Tsetse Flies, Glossina Spp. (Diptera: Glossinidae), Jan Žďárek, František Weyda, Mathayo M.B. Chimtawi, David L. Denlinger

All Peer-Reviewed Publications

This study examines the external and internal anatomy of the polypneustic (respiratory) lobes in 8 species of tsetse larvae (Diptera: Glossinidae). In the more primitive fusca group, the respiratory lobes are either ring-like (Glossina longipennis) or partially divided into 2 lobes (G. brevipalpis). Two distinctly separated lobes are present in the palpalis group (G. palpalis, G. tachinoides, G. fuscipes) and in the morsitans group (G. morsitans, G. pallidipes, G. austeni). Air enters the polypneustic lobes through narrow slits (stigmata) on the tips of numerous small spiracular papillae that are arranged in rows on both the outer and inner surfaces of …

Genetics Of Resistance To Aphis Craccivora In Cowpea, S. M. Githiri, K. Ampong-Nyarko, E. O. Osir, P. M. Kimani

All Peer-Reviewed Publications

Inheritance of aphid resistance and allelic relationships among sources of resistance was studied in the parents, F1, F2, F3, and backcross populations of cowpea crosses. Each 4-day old seedling was infested with five fourth-instar aphids. Seedling reaction was recorded 14-16 days after infestation when the susceptible check was killed. The segregation data from eight crosses between resistant and susceptible cowpea cultivars indicated that aphid resistance was inherited as a monogenic dominant trait. Segregation data from crosses among eight resistant cultivars indicated that one or two loci and modifier(s) were involved in the expression of resistance to aphids. It was suggested …

Identification Of Major Components Of Larviposition Pheromone From Larvae Of Tsetse Flies Glossina Morsitans Morsitans Westwood And Glossina Morsitans Centralis Machado, R. K. Saini, A. Hassanali, J. Andoke, P. Ahuya, W. P. Ouma

All Peer-Reviewed Publications

The presence of pheromones produced by larvae of Glossina morsitans morsitans and G. m. centralis, respectively, which attract gravid females and result in aggregation of pupae, is confirmed. Behavioral experiments indicated that females preferred to larviposit over moist sand conditioned by previously allowing larvae to pupariate in it. Similar results were obtained with filter papers contaminated with the prepupariation excretions of larvae and with volatiles collected from larvae prior to pupariation. n-Pentadecane and n-dodecane were identified as the dominant electrophysiologically active components of the larviposition pheromones of G. m. morsitans and G. m. centralis, respectively, by GC-EAD and GC-MS analysis …

Chemoecological Role Of Mammalian Urine In Host Location By Tsetse, Glossina Spp. (Diptera: Glossinidae), L. Chuka Madubunyi, A. Hassanali, W. Ouma, D. Nyarango, J. Kabii

All Peer-Reviewed Publications

Trap catch size was used to investigate whether Glossina pallidipes and G. longipennis could distinguish between the urine of the African buffalo, cattle, and waterbuck at Nguruman in southwest Kenya, NG2G traps baited with aged urine of these bovids caught significantly more of each tsetse than did the controls. The mean catch of either tsetse species in traps baited with aged urine of buffalo and cattle (tsetse hosts) and waterbuck (a nonhost) did not differ significantly. Aged urine from both tsetse hosts (buffalo and cattle) and the nonhost (waterbuck) was found to contain 4-cresol and 3-n-propylphenol in about the same …

Reproductive Performance And Population Dynamics Of Cowpea Aphid (Homoptera: Aphididae) On Leaf Extracts Of Resistant And Susceptible Cowpeas, I. Billy Annan, Ward M. Tingey, George A. Schaefers, Kailash N. Saxena

All Peer-Reviewed Publications

Membrane feeding studies were conducted to determine the effects of raw juices and chemical extracts of leaves of aphid-resistant (ICV-12) and aphid- susceptible (ICV-1) cultivars of cowpea [Vigna unguiculata L. (Walp.)], on the survival, growth, and reproduction of cowpea aphid Aphis craccivora Koch. Life table and demographic statistics of the cohort population and subsequent generations were estimated. Compared to ICV-1, the leaf juices and chemical extracts of ICV-12 exhibited significant (P ≤ 0.05) adverse effects on aphid survival, growth, and reproduction. Raw leaf juice and ethyl acetate extract of ICV-12 in both water and sucrose significantly (P ≤ 0.05) limited …

Physiological Responses And Central Nervous Projections Of Antennal Olfactory Receptor Neurons In The Adult Desert Locust, Schistocerca Gregaria (Orthoptera: Acrididae), B. S. Hansson, S. A. Ochieng, X. Grosmaitre S Anton, P. G.N. Njagi

All Peer-Reviewed Publications

Olfactory receptor neurons present in two morphological sensillum types on the male Schistocerca gregaria antenna were for the first time investigated physiologically when stimulated with behaviourally relevant odours. Neurons present in trichoid/basiconic sensilla showed clear excitatory responses to compounds present in the male-produced aggregation pheromone and also to a plant produced compound. Sensilla could be categorised physiologically according to the responses of their receptor neurons to the tested stimuli. Also receptor neurons present in sensilla coeloconica responded to aggregation pheromone components, but always in an inhibitory fashion. These neurons could, however, be excited by a plant produced compound and by …

1,8-Cineole: An Attractant For The Banana Weevil, Cosmopolites Sordidus, Isaiah O. Ndiege, Willam J. Budenberg, Dalmas O. Otieno, Ahmed Hassanali

All Peer-Reviewed Publications

1,8-Cineole was identified as one of the electrophysiologically active components of the volatiles from banana cultivars susceptible to the banana weevil. It was also shown to be an attractant for the banana weevil Comopolites sordidus in laboratory behavioural bioassays. The resistant cultivar did not contain 1,8-cineole. β-Phellandrene, which exhibited electrophysiological activity, but did not show any attraction to the banana weevil, was found only in the resistant banana cultivar.

Mitochondrial Dna Variation In Screwworm, David B. Taylor, Allen L. Szalanski, Richard D. Peterson Ii

Department of Entomology: Faculty Publications

Polymerase chain reaction-restriction fragment length polymorphism (PCRRFLP) analysis was used to characterize mitochondrial DNA (mtDNA) variation in screwworms, Cochliomyia hominivorax, and secondary screwworm, C. macellaria, from the Caribbean, North America and South America. Four amplicons, totaling 7.1 kb, were analysed with sixteen restriction enzymes. A total of 133 restriction sites was observed in the two species, 104 in C. hominivorax, of which nineteen were variable, and ninety-five in C. macellaria, none of which was variable. Fourteen mtDNA haplotypes were observed among eighteen C. hominivorax examined. Mean divergence between C. hominivorax haplotypes (d) was 0.0064 …

Oviposition And Calling Behavior Of Codling Moth (Lepidoptera: Tortricidae) In The Presence Of Codlemone, Thomas J. Weissling, Alan L. Knight

Department of Entomology: Faculty Publications

The effect of the major component of codling moth, Cydia pomonella (L.) sex pheromone (codlemone, E,E-8,10-dodecadien-l-ol) on female calling and oviposition behavior was investigated. Calling by virgin females was similar between moths placed in sealed containers containing codlemone or codlemone-free air. However, when pheromone emitted by females was removed by a continuous air stream, calling in codlemone-permeated air was significantly higher than in clean air. The temporal pattern of calling was unaltered by the presence of codlemone. In a laboratory no-choice test, oviposition rates by codling moth females were similar in the presence of codlemone and in codlemone-free air. However, …

Molecular Differentiation Of Alfalfa Weevil Strains (Coleoptera: Curculionidae), S. J. Erney, K. P. Pruess, S. D. Danielson, T. O. Powers

Department of Entomology: Faculty Publications

Mitochondrial DNA was amplified and sequenced from eastern, western, and Egyptian strains of alfalfa weevil, Hypera postica (Gyllenhal). Eastern and Egyptian weevils differed at only 2 nucleotide sites in 1,031 base pairs sequenced; western weevils differed by 5% sequence divergence. Three restriction sites were identified which separated eastern and western haplotypes. No intrastrain polymorphism was detected in 150 weevils from Nebraska. Collections from Lincoln in eastern Nebraska and Scottsbluff in western Nebraska were fixed for the eastern and western haplotypes, respectively. Eastern and western haplotypes were found together in the same fields in a broad overlap region in central Nebraska.

Population Genetics And Gene Variation In Screwworms (Diptera: Calliphoridae) From Brazil, David B. Taylor, Richard D. Peterson Ii, Gonzalo E. Moya-Borja

Department of Entomology: Faculty Publications

Allozyme variation in New World screwworm, Cochliomyia hominivorax (Coquerel), populations from Brazil was examined. Variability was observed in 8 of 13 enzyme loci and the frequency of the most common allele was <0.95 for seven loci. Observed and expected heterozygosities were 0.159 and 0.165, respectively. Comparisons of the Brazilian populations with previously studied populations from Costa Rica resulted in Nei's genetic distances of between 0.000 and 0. 006, with the greatest distance being between populations within Brazil. Comparisons with Mexican populations using only three loci resulted in genetic distances ≤0.031. Goodness-of-fit statistics for Hardy-Weinberg equilibrium and Wright's F statistics indicated small deviations from expected equilibrium genotype frequencies and low levels of differentiation between populations within Brazil. Differentiation among screwworm populations from Brazil, Costa Rica, and Mexico was minimal.

Estimation Of Rice Yield Losses Due To The African Rice Gall Midge, Orseolia Oryzivora Harris And Gagne, Souleymane Nacro, E. A. Heinrichs, D. Dakouo

Department of Entomology: Faculty Publications

The African rice gall midge, Orseolia oryzivora Harris and Gagne (Diptera: Cecidomyiidae), is an important pest of rice, Oryza sativa, in Burkina Faso as well as other countries in West and East Africa. In spite of its importance, little is known regarding the relationship between gall midge populations and grain yield losses. To determine yield losses, the gall midge was reared in cages, and adult midges were placed on caged plants of the rice variety ITA 123 at different population levels. The seven treatments consisted of different numbers of insects infested on the plants: 0 insect pairs (noninfested check), …

Volatile Infochemicals Used In Host And Host Habitat Location By Cotesia Flavipes Cameron And Cotesia Sesamiae (Cameron) (Hymenoptera: Braconidae), Larval Parasitoids Of Stemborers On Graminae, Adele J. Ngi-Song, William A. Overholt, Peter G.N. Njagi, Marcel Dicke, Jonathan N. Ayertey, Wilbert Lwande

All Peer-Reviewed Publications

Female Cotesia flavipes Cameron and Cotesia sesamiae (Cameron) were attracted to odors in a Y-tube olfactometer from uninfested maize (Zea mays L.), sorghum [Sorghum bicolor (L.)]. and napier grass (Pennisetum purpureum Schumach). In dual choice tests. Cotesia flavipes showed a preference for maize over sorghum, while maize and napier grass were equally attractive. In contrast, Cotesia sesamiae preferred volatiles from sorghum and napier grass over those from maize. The two parasitoids were significantly more attracted to maize infested with the stemborers, Chilo partellus (Swinhoe), Chilo orichalcociliellus Strand, Sesamia calamistis Hampson, and Busseola fusca (Fuller), than uninfested maize. In dual choice …

Oviposition Behavior Of Cotesia Flavipes And Goniozus Indicus, Larval Parasitoids Of The Lepidopteran Stemborer Chilo Partellus, Keiji Takasu, William A. Overholt

All Peer-Reviewed Publications

Observing the opposition behavior of ingress-and-sting larval parasitoids of lepidopteran stemborers is difficult due to the cryptic feeding behavior of the hosts. A method for observing their opposition behavior was developed. An individual stemborer larva was introduced into a glass tube (0.7 cm in diameter; 7 cm in length) which contained a piece of maize stem (0.5-0.6 cm in diameter; 4-5 cm in length). The larva was allowed 14-20 h to feed on the maize and produce frass before introducing a single adult female parasitoid. Using this method, we observed the endoparasitoid Cotesia flavipes (CAMERON) and the ectoparasitoid Goniozus indicus …

Responses Of Nymphs Of Desert Locust, Schistocerca Gregaria To Volatiles Of Plants Used As Rearing Diet, Peter George N. Njagi, Baldwyn Torto

All Peer-Reviewed Publications

Gregarious nymphs of the desert locust, Schistocerca gregaria (Forsk.) (Orthoptera: Acrididae) were more attracted to volatiles from mechanically damaged food plants used for rearing than to either the undamaged or damaged food plants not used as diet in Y-tube olfactometer assays. Comparative analysis of the volatile emissions from plants used for rearing and food plants not used for rearing, e.g. Sorghum bicolor, Pennisetum clandestinum, Schouwia thebaica, wheat (Triticum sp., var. 'Nyangumi'), Zygophyllum simplex, Heliotropium undulatum and Tribulus terrestris was carried out by GC, GC-EAD and GC-MS. Significant quantitative and qualitative differences were found in the volatile emissions and olfactory responses …

Effects Of Shifting To Crowded Or Solitary Conditions On Pheromone Release And Morphometrics Of The Desert Locust, Schistocerca Gregaria (Forskal) (Orthoptera: Acrididae), Arop Leek Deng, Baldwyn Torto, Ahmed Hassanali, E. E. Ali

All Peer-Reviewed Publications

We have studied the effect of shifting the desert locust, Schistocerca gregaria (Forskal) from crowded to solitary conditions, or vice versa on the emission of the adult aggregation pheromone (as measured by released phenylacetonitrile) and compared this with changes in morphometrics. Adult males of the F0 generation resulting from shifting crowd-reared (gregarious) hoppers, fledglings or mature adults (aged 20-22 days after the final moult) to solitary conditions did not produce phenylacetonitrile, similar to solitary-reared adults. Conversely, adults of the F0 generation resulting from shifting solitary-reared (solitarious) hoppers, fledglings or mature adults to crowded conditions produced pheromone at levels which were …

Nebline, December 1995

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Horticulture

Rural $ense

Family Living

4-H & Youth

Environmental Focus

Community & Leadership Development

Extension Calendar

Expanded Food and Nutrition Education Program (EFNEP)

Nebraska Association for Family and Community Education News

and other extension news and event

Flea News 51 (December 1995), Robert E. Lewis

Flea News

Obituaries:George MacKenzie Dunnet (April 19, 1928-September 11, 1995); William Livingston Jellison (January 28, 1906-November 7, 1995)

Miscellanea

Siphonaptera literatue

Hexapod Herald - Vol. 7, No. 28, December 1, 1995

Hexapod Herald and Other Entomology Department Newsletters

Grants

Publications

Congratulations

Miscellaneous

Announcements from the office

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Hexapod Herald - Vol. 7, No. 27, November 16, 1995

Hexapod Herald and Other Entomology Department Newsletters

Grants

Publications

Congratulations

Miscellaneous

Announcements from the office

Department travelers

Calendar of events

Deadline

Nebline, November 1995

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Horticulture

Rural $ense

Family Living

4-H & Youth

Environmental Focus

Community & Leadership Development

Extension Calendar

Expanded Food and Nutrition Education Program (EFNEP)

Nebraska Association for Family and Community Education News

and other extension news and event

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

Hexapod Herald - Vol. 7, No. 26, October 31, 1995

Hexapod Herald and Other Entomology Department Newsletters

Grants

Publications

Congratulations

Miscellaneous

Deadlines

Announcements from the office

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Hexapod Herald - Vol. 7, No. 25, October 17, 1995

Hexapod Herald and Other Entomology Department Newsletters

Grants

Publications

Congratulations

Miscellaneous

Deadlines

Announcements from the office

Calendar of events

Nebline, October 1995

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Horticulture

Rural $ense

Family Living

4-H & Youth

Environmental Focus

Community & Leadership Development

Extension Calendar

Expanded Food and Nutrition Education Program (EFNEP)

Nebraska Association for Family and Community Education News

and other extension news and events