Summer 2002 participants ready for a tour of the facilities

For over 20 years CMAVE has been providing employment and learning opportunities for students interested in working at one of the top entomological research centers in the world. In the summer of 2002, CMAVE sponsored four high school student apprentices, selected from high schools in Alachua county, and nine college student interns, chosen from colleges around the country, with ARS funds.   We also hosted five students from area high schools through the Youth Employment Start (YES) program, a federally funded work-training program administered by Santa Fe Community College.   In addition, we welcomed five students from the Student Science Training Program (S.S.T.P.), a summer program run through U.F. to provide research experience to high school students from around the state.  This page contains links to information about their summer projects.

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Summer Apprentices
Click on the pictures below for information about the summer apprentices

Alyce NeJame

Brett Miller

Edwina Cummings

Kevin Thomas

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Summer Interns
Click on the pictures below for information about the summer interns

Akers Pence	Laura Parenteau	Mirian Hay-Roe
Janet Lane	Elizabeth Rondon	William Allen
Chip Hunter	John Profumo	Ryan Stype

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Youth Employment Start (YES) Students
Click on the picutures below for information about the YES students

Mwitse Ansoanuur

Mark Musselman

Keishaundra Leroy

Jason Hill

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Student Science Training Program (SSTP)
Click on the pictures below for information about the SSTP students

Kay Furman

Cedric Chan

Melissa Chen

Archna Eniasivam

Abdias Rodrigues

Jerry Hogsette, Mentor

Inspecting the cages, each one containing 25 female house flies, and an experimental poison bait made from boric acid and sugar.

This summer Alyce NeJame worked on three projects involving house flies. One examined the effectiveness of poison baits made from various ratios of boric acid to sugar, and the effect of freeze drying, and later reconstituting the baits. Another involved the use of bait strips made from Kimwipes, boric acid, and sugar, and the third involved testing of the GT200 fly trap, a device employed by supermarkets to eliminate house flies that have entered the stores.

Inspecting the kill from an experiment using the GT200 fly trap with Sylvania Quantum bulbs.

The GT200 fly trap with dead house flies stuck to the light colored paper behind the Sylvania Quantum (UVA emitting) lamps. Experiments show that the flies are far more likely to become trapped on the light colored sticky paper than dark sticky paper. (Food stores would prefer to use darker paper to mitigate the gross appearance of the flies.)

Alyce's Abstract:

Reconstituting Freeze Dried Boric Acid Sugar Baits for Musca domestica

The objective of this project was to see if freeze-drying and then reconstituting boric acid baits in sugar solutions would affect the repellency observed in the initial liquid form. Based on a previous study with liquid bait solutions, Musca domestica (L.), the house fly, became repelled by a 2.5% boric acid sugar solution. Upon retesting, we found that the LC50 for the initial liquid solutions was ~3.6%. The LC50 was ~83.4%. After reconstituting the freeze-dried baits, the LC50 was found to be ~4.1%. Because of the overlapping confidence intervals, there is no difference between the LC50s of the initial solutions and the reconstituted solutions. There seems to be a difference in how fast the boric acid works upon the flies based on the form it is ingested. The liquids seem to work faster than the freeze-dried solid and the LT50 of the reconstituted liquid is decreased by several more hours than the LT50 of the original solutions. The LT50s of the negative controls indicate no repellency even at the highest doses tested.

 

Steve Ferkovich, Mentor

Measuring protein concentration using the spectrophotometer.

This summer Brett Miller participated on a project in which he analyzed proteins in instect tissue samples.

Placing protein samples in the ultracentrifuge.

 

Supervised by Margaret Martin

Entering data on reprints into the ProCite database program.

This summer Edwina Cummings assisted the Fire Ant & Household Insects Research Unit by making database entries, organizing files, and performing a variety of office duties

At work in the IFAHI copy room.

 

Greg Knue, Mentor

Using the electric pipetaid to draw fluid for use in the centrifuge tube.

This summer Kevin Thomas worked on a project that attempted to isolate a virus that was previously known to infect the red imported fire ant. Both naturally discovered and lab raised ant colonies were examined for traces of the elusive virus, which may one day be employed in efforts to control wild fire ant populations. Colonies were first blended in a blender with water, then strained, and then subjected twice to the centrifuge to separate component parts of the ants. The resulting matter was placed in the electron microscope to look for the virus.

Removing the centrifuge tubes containing the pellets that resulted from 30 minutes of processing in the centrifuge at 11,000 RPM. The pellets will later be resuspended in a solution of water and Ludox, and placed back into the centrifuge, at 15,000 RPM, for 20 minutes.

A close up look at the pellets containing the fire ant particles.

Kevin's Abstract:

Biological Control of Fire Ants: Virus Research

In the 1940's the Red Imported Fire Ant (Solenopsis invicta) was accidentally introduced into the USA. The fire ants spread and now cover over 320 million acres in the US. The USDA-ARS has been conducting research for many years to control the Red Imported Fire Ant. An area that has recently shown promise is the use of biological controls. Two promising biological controls have already been found and are been used against the fire ants. They are phorid flies (Pseudacteon spp.) and a protozoan pathogen (Thelohania solenopsae). Another important pathogen that probably exists in fire ants is viruses. If we find one, we can use it to better control fire ants.

 

Don Silhacek, Mentor

Examining the diet cups for eggs laid by Plodia moths infesting a mini warehouse. Akers is seen here in a room during "octron gold guard" lighting conditions.

Akers Pence spent the summer examining the effects of various unusual lighting conditions on the reproduction of Indianmeal moths, Plodia interpunctella, in simulated food storage warehouses. Data were analyzed using the Surfer computer program.

Standing in the warehouse under conditions known as "full red treatment."

Akers' Abstract:

Investigating the Effects of Colored Light and Photoperiod on Movement and Reproductive Success of Plodia interpunctella, Indianmeal Moth

Movement of adult moths within a miniature warehouse was recorded at four and eight hour intervals. Plots of these data were used to compare the effects of different wavelengths, light intensities, and photoperiods in twenty-two experiments. Reproductive success of Plodia interpunctella was measured by counting progeny from eggs laid in commodity cups in each treatment. Our object is to create a hostile environment that will limit moth infestation of commodities stored in commercial warehouses. The most promising results were from treatments with amber or green light, which show significant reductions in progeny per moth.

 

Don Silhacek, Mentor

Observing Galleria mellonella (wax moth) eggs under a microscope.

This summer Laura Parenteau worked on two projects. The first project involved experimenting with the diet of Plodia interpunctella. The second project involved development of a diet for Galleria mellonella that can be produced more efficiently, but which performs as well as the existing diet.

Weighing the Plodia larvae.

Laura's abstract:

The Effects of Various Nutrients on the Larval Growth of Plodia interpunctella

The purpose of this study was to alter a cereal product so it would not support the growth of Plodia larvae but would keep its nutritional value for human consumption. This approach to controlling the moth substitutes for the conventional use of pesticides. An example of a cereal product that does not support larval growth is corn flakes. To determine why this product fails, experiments were performed to try to improve the product. These experiments helped to determine which nutrients are required by Plodia larvae for growth. Most tests involved supplementing the corn flakes with various nutrients. Several nutrients were found to support larval growth; their chemical components will be used in future experiments to help refine this approach to pest control.

 

Cameron Lait, Mentor

Loading samples of regurgitant into the High Performance Liquid Chromatograph to identify the compounds that are in it. The monitor at top center displays the results of the analysis.

Loading the ultracentrifuge with vials containing microsomes and cytosol that were previously separated from other material. The ultracentrifuge will be run at 32,000 RPM at 4°C for 90 minutes to isolate the microsomes for protein analysis.

A close-up look at tobacco leaf damage by the tobacco hornworm, Manduca sexta. This plant was sprayed with the amino acid valine.

Manduca sexta feeding on the tobacco plant control.

Mirian's Abstract:

Coupling of Amino Acids to Linolenic Acid in vitro by Tobacco Hornworm Microsomes.

Plants actively produce and release volatile chemical signals in response to fatty acid amide (FAA) elicitors found in the oral secretions of attacking Lepidopterous herbivores. These volatile chemicals play a major role in enabling natural enemies of the herbivores, such as insect parasitoids, to locate hosts. The FAA elicitors N-linolenoyl-L-glutamine and N-linolenoyl-L-glutamic acid have been identified in tobacco hornworm (THW) oral secretions and it was recently determined that enzymes present in several of the caterpillar's tissues were involved with their biosynthesis. The specificity of enzymes responsible for the coupling of amino acids to linolenic acid to yield elicitors has not been previously studied. We determined that 4 hydrophilic (polar) and 4 hydrophobic amino acids could be coupled to linolenic acid by THW microsomes at an optimum pH of 8.0. Glutamic acid, found in one of the THW elicitors, did not couple to linolenic acid under the same experimental conditions as the other amino acids that did couple.

 

Richard Mankin, Mentor

Taking notes on the locations of female medflies, Ceratitis capitata,  at a chamber set up to reproduce the male medfly courtship song.

This summer Janet Lane sought to evaluate the effectiveness of newly developed acoustic techniques for trapping female Mediterranean fruit flies. The traps she studied incorporated the courtship song of the male medfly, which was played back using a loudspeaker set up in indirect contact with either a sticky paper or multilure trap. It is hoped that this new trapping method will increase the numbers of unmated females lured into the traps.

A close-up look at the apparatus directing male song toward a sticky paper trap. The black object on the right is a small loudspeaker that reproduces the male's sound, which is transmitted to the paper via the funnel. (The "song" is made by the male's wing beats.)

A look at a multilure medfly trap set up with the male's courtship song being played into it from below. The white ball in the center of the trap houses 4 male flies which emit pheromones to increase the trap's attractiveness to females.

A magnified view of a female medfly, showing the ovipositor which projects from the abdomen.. (Actual length of the female is about 6 mm.)

A magnified view of a male medfly. (Actual length of the male is about 6 mm.)

Janet's Abstract:

Response of the Female Medfly, Ceratitis capitata, to the Playback of the Male Mating Call during Bioassay Experiment

Preventing infestations of the Mediterranean fruit fly, Ceratitis capitata, has cost the United States over $800 million yearly. Previous monitoring methods only trap male and mated-females and do not efficiently trap virgin and re-mating female flies. A potential way to attract the virgin and remating flies is to attract them to an "artificial male", using a new trapping method that broadcasts a recorded male calling song. Initial studies in bioassay chambers by Postdoctoral Associate James Anderson resulted in more female flies attracted to sticky paper next to a speaker broadcasting a recorded male call than to a sticky paper near a silent apparatus or sticky paper by itself. The results of new experiments I conducted suggest that the traps with broadcasted sound continue to attract more flies than a silent apparatus-control, or sticky paper. In the new experiments the effect of sound was not statistically significant. This may be a result of the remodeled bioassay chambers. Since the sample size was only six, more experiments should be run that reduce the effects of specific confounding variables. This may increase the significance of sound and confirm the original study. In another set of experiments male medflies were enclosed in mesh containers near the sound and control apparatuses. The prediction is that males releasing sex pheromones near the broadcast song will attract more females than males without the song or a control without the song or males. The results are inconclusive because a larger sample size is needed.

 

Eric Schmelz, Mentor

Drying down the plant material with nitrogen to evaporate the ether. This procedure is followed by adding water to the plant material in preparation for collecting the plant volatiles.

Elizabeth Rondon spent the summer conducting research on hydroponically grown corn plants of a type used for animal feed. Her activities included collecting volatiles, and measuring jasmonic acid levels from excised leaf tissue.

Loading vials of plant volatiles into the gas chromatograph for analysis.

Elizabeth's Abstract:

The Effect of Nitrogen Availability on Plant Defense Responses to Insect Elicitors: Local and Systemic Relationships between Volicitin, Jasmonic Acid, and Volatile Emissions

Plants respond to herbivore feeding by releasing volatiles. These volatiles can serve as attractants for natural enemies. For example, parasitoids use the volatile blends to find appropriate hosts for oviposition. Jasmonic acid is a plant hormone that is involved in plant defense responses. Both insect attack and jasmonic acid trigger the emission of volatiles that attract natural enemies. Plants recognize herbivory from the elicitors present in the oral secretions of the herbivores. Volicitin is an elicitor identified from beet armyworm secretions. Volicitin triggers the release of volatiles, in part, by regulating the levels of jasmonic acid. Plant defenses often vary based on nutrient availability. The study began using plants with different levels of nitrogen, low nitrogen (0.2 mM) and high nitrogen (2 mm). Plants were wounded in the presence and absence of volicitin, harvested for jasmonic acid, and volatiles collected. To examine the local and systemic areas, the distal parts of the leaves were physically separated from the local areas around the wound site. Only the local areas of the high nitrogen plants responded to the elicitor. The low nitrogen plants were extremely sensitive to the elicitor both locally and systemically. Differences in the jasmonic acid levels may explain the increased sensitivity of the low nitrogen plants.

 

Susie Legaspi, Mentor

William Allen sexing a spined soldier bug, Podisus maculiventris (Say) under a stereo microscope.

This summer William Allen sought to determine what effect, if any, diet has on the fecundity of the spined soldier bug. Specifically, he fed his subjects five different prey species to see if there was any difference in egg laying output as a result of available prey.

William Allen preparing a pheromone trap to collect the spined soldier bug, Podisus maculiventris (Say).

William's abstract:

Effect of prey type on fecundity of spined soldier bug, Podisus maculiventris (Heteroptera: Pentatomidae)

Previous studies on prey preference of Podisus maculiventris indicated its preference for the beet army worm (BAW) to other prey choices. The objective of this study is to determine the effect of prey type on the fecundity or egg production of P. maculiventris. A total of 5 different prey species were given to the female Podisus. These were beet army worm (BAW), Spodoptera exigua; fall army worm (FAW), Spodoptera frugiperda; cabbage looper (CL), Trichoplusia ni; greater waxmoth (WAX), Galleria mellonella and yellow mealworm (MW), Tenebrio molitor. We will also determine the level of vitellogenin, a protein vital to egg production. Each female was mated with a male every 3 days after the start of the experiment. The number of eggs laid per day were recorded. Preliminary results indicated no significant difference in the mean number of eggs laid per female under the different feeding treatments at 7 days after the start of the experiment. Further studies on the effect of prey type on fecundity and amount of vitellogenin at 15, 22 and 30 days after the start of experiment are ongoing.

 

Prem Chourey, Mentor

Cloning genes using bacteria grown in petri dishes.

Chip Hunter worked in the Crop Genetics unit this summer. His tasks included pollinating corn plants out in the field, running sugar assays to determine the amount of soluble sugars in pollen samples, and cloning corn genes in bacteria cultures in an effort to isolate the genes important in starch biosynthesis required for pollen development.

Setting up a gel electrophoresis to separate DNA according to size.

 

Dr. Rui-De Xue and Dr. D.R. Barnard, Mentor

At the chilling table. Live mosquito specimens are taken from the rearing chambers seen in the background, and examined under the microscope. This ensures that no mutant individuals contaminate the strain under study.

John Profumo studied the behavior of three strains of Aedes aegypti mosquitos: normal, white-eye, and redeye This species is known to transmit yellow fever to people, and studies of the behavioral differences between various strains may lead to new methods of controlling their populations in the wild.

Testing host attack response using the WHO test kit. This is one of the behavioral experiments John conducted this summer. The mosquitos are placed in the top chamber of the cylinder, then allowed access to the lower chamber via the sliding door. Different strains' response times to attack the host (John) were measured and compared.

Using the dissecting microscope to count the number of mature eggs in the ovaries of the mosquito specimens.

John's Abstract:

Behavioral Study of Mutant Aedes aegypti

For years the populations of red-eye and white-eye mutant strains of Aedes aegypti were kept in quarantine, perceived as a possible genetic study population, but their behavior was never examined. The mutant mosquitoes might exhibit behavioral traits that would make them a viable method of bio-control against the potential disease vector and probable annoyance that wild mosquitoes have become. Such traits as inability to find hosts, reduced fecundity, or even increased effectiveness of repellents would all make these mutant mosquitoes an extremely attractive future method for population control. The redeye, white-eye, and normal strains of Aedes aegypti mosquitoes were used to perform different behavioral tests. The olfactometer was used to compare the ability of the mosquitoes to locate hosts through detection of human scent or attractant. The WHO test kits were used to test the rapidity with which each strain would begin feeding and become satiated from a blood meal. Mosquitoes were also dissected, and eggs laid were counted in order to compare the fecundity of the strains after blood meals. Standard repellency tests were performed to see if the strains had any effect on the duration of protection provided by various types of commercially available repellents. These experiments revealed that the normal strain was most adept at locating the host in the olfactometer; the redeye strain could also finds hosts, but only one of the white-eyed mosquitoes ever found its host. In the WHO test kit the red-eyed mosquitoes were significantly faster than the other two strains, which were similar in speed. There was no difference found in the duration of blood feeding amongst the three strains. Fecundity tests revealed that the white-eye strain produced significantly less eggs than the other strains. DEET repellent (7-15%) provided hours of protection from all strains and all strains reacted similarly to varying repellents. The behavior of the white-eye strain seems to lend itself to uses in bio-control, because the females cannot find hosts well and they do not lay many eggs even if they are able to bloodfeed.

 

Stuart Reitz, Mentor

The destructive diamondback moth.

Ryan Stype's project this summer was to determine if the predatory stink-bug Podisus maculiventris, and the parasitoid wasp Cotesia plutellae, act additively, antagonistically, or synergistically in efforts to control diamondback moth populations in cabbage.

A healthy cabbage.

A cabbage that has been largely devoured by diamondback moths.

Watering the test cabbages.

Performing a meticulous inspection of each leaf on each cabbage.

Ryan's Abstract:

Interactions Between Podisus maculiventris (Say) (Heteroptera: Pentatomidae), Cotesia plutellae Kurdj. (Hymenoptera: Braconidae) and Plutella xylostella (L.) (Lepidoptera: Plutellidae) in Cabbage

The diamondback moth, Plutella xylostella (L.), is the primary pest of brassicas in the southeast largely due to insecticide resistance. Biological control offers an alternate solution to insecticidal treatments. Furthermore, little is known of the interactions between predators and parasitoids that exploit the same resource. I am assisting in experiments testing if Podisus maculiventris and Cotesia plutellae have additive, antagonistic, or synergistic effects on diamondback moth populations in cabbage (Brassica oleracea var. capitata) by comparing moth populations and plant damage in replicated field cages containing 1) diamondback moth, 2) diamondback moth with P. maculiventris, 3) diamondback moth with C. plutellae, 4) diamondback moth with P. maculiventris and C. plutellae. These results will provide information addressing interactions between predators and parasitoids and alternate methods for suppression of diamondback moth populations in Florida.

 

Supervised by Eric Kaufmann

Hard at work updating the Publications List for the CMAVE web site.

This summer Mwitse Ansoanuur performed a valuable service for the entire research center by updating and organizing the Publications List web page, which lists the journal articles and patents published by CMAVE scientists and staff over the last several years. His work included the addition of hyperlinks to the growing number of articles now being published online, as well as in print. When he had a spare moment, Mwitse was also available to assist CMAVE staff with a variety of computer related tasks.

Leafing through the Journal of Medical Entomology, one of many scientific journals CMAVE scientists publish in, which has some of its articles now available online.

 

Supervised by Bob Vander Meer

Transferring fire ant workers from one colony to another for an aggression test.

This summer Mark Musselman worked on a study of diet and aggression in colonies of red imported fire ants. Nine of the colonies were fed crickets, and sucrose in water. Six additional colonies were given a similar diet which also included 3-iodo-tyrosine. The colonies given the chemical supplement were found to exhibit more aggressive behavior.

Feeding crickets to the ants.

 

Supervised by Peggy Zelonka, Valerie Malcolm, and Kathleen Smitherman

Going through the emergency contact information notebook, while speaking to a high level government official.

This summer Keishaundra "Qui Qui" Leroy performed office duties for three of the six research units at CMAVE: Chemistry, Behavior & Biocontrol, and Postharvest & Bioregulation. Her activities included updating the historical reprint files, filing, copying, organizing and distributing time sheets, and sending scientific journal reprints to people in countries throughout the world, including the United Kingdom, Australia, and Japan.

Working on Emergency Information Cards for Building 11 employees.

 

Supervised by Bernie Sparks

Holding a jar containing sawtoothed grain beetles in oatmeal.

This summer Jason Hill worked in a variety of areas. He set up rearing jars with diet for the red flour beetle, maize weevil, and sawtoothed grain beetle. He also assisted in bioassay wind tunnel experiments, and created the flyer detailing the agenda for the lab tours conducted annually for all the CMAVE summer employment program participants.

Preparing to create the flyer announcing the lab tours for the summer program participants.

 

Uli Bernier, Mentor

Drawing 75 female mosquitos into the cylindrical trap at the end of the cage, using a human hand as bait. The mosquitos will then be loaded into the olfactometer for experiments to determine the efficacy of new mosquito repellents.

Kay Furman conducted experiments this summer on the mosquito, Aedes aegypti, which is known to transmit yellow fever to humans. Her work is part of an effort to develop catnip oil for use as a mosquito repellent. Specifically, she is trying to determine the attractant inhibitor and repellent properties of catnip oil, in order to compare those properties to the properties of DEET.

Gauging the attractiveness of Kay's left hand in the olfactometer.

 

Steve Ferkovich, Mentor

Attending the jars in which insects feed on the experimental diet for 6 days.

This summer Cedric Chan participated on a project aimed at improving the diet of beneficial insects, which can be raised in the laboratory and released into the wild to eat insect pests.

Transferring a protein solution into a dialyzer.

 

Steve Ferkovich, Mentor

Holding one of the jars used to house the research specimens.

This summer Melissa Chen participated on a project aimed at improving the diet of beneficial insects, which can be raised in the laboratory and released into the wild to eat insect pests.

Counting eggs under the dissecting microscope.

 

Bob Vander Meer, Mentor

Sealing the ampoules - the small glass vessels that contain a rubber septum saturated with either hexane alone (the control), or hexane plus the contents of the poison sac. These ampoules are used as individual storage devices for the rubber septa, which serve as surrogate queens during lab experiments.

Archna Eniasivam studied laboratory colonies of the red imported fire ant. Among her duties were locating the queen, extracting the poison sack, and testing the attractiveness of various components of the poison sac to worker ants during controlled experiments.

Conducting the surrogate queen bioassay.

 

Don Silhacek, Mentor

Counting eggs under the dissecting microscope.

This summer Abdias Rodrigues studied the effects of lighting conditions on the fertility of the Indianmeal moth, Plodia interpunctella. Mini warehouses containing moth infestations were illuminated with either white, red, or far red (a mixture of red and blue flourescent) light. Specifically, Abdias examined the hatchability of the eggs, and emergence of pupae.

Writing up the results of weeks of observations.