Summer 2001 Participants Group Photo

In the summer of 2001, CMAVE sponsored six high school student apprentices, selected from high schools in Alachua county, and seven college student interns, chosen from colleges around the country, with ARS funds.   We also hosted four 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 picture for information about the summer apprentices and their research project

Rena Bryan	Brett Miller	Charles Fletcher
Kimberly Bass	Dwayne McKnight	Alyce NeJame

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

Melanie Gray

Laura Parenteau

Ranyelle Craig

Andrew Kao

Christy Copeland

Felicia Haynes

Erica Simbro

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

Dorel Humphrey

Jakeisha Robinson

Ernest Jackson

Mwitse Ansoanuur

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

Rose Mikulski

Jeffrey Barrientos

Pooja Gupta

Brandon S. Verblow

Ann Mary Joseph

 

Yasmin Cardoza, Mentor

Rena Bryan studied what effect various Xanthomonas bacterial concentrations had on the volatile emissions of pepper plants. She also examined the feeding preference of the beet armyworm, Spodoptera exigna, on healthy leaves vs. those infected by Xanthomonas.

Putting internal standard into sample vials for GC analysis.

Inoculating one pepper plant in one of the dilutions of bacteria.

Feeding choice experiment. Healthy pepper plant is on the left; infected on the right. Leaves from each plant extend into the shallow cage at center, where beet armyworms are contained.

A look at the beet armyworm (third instar)

Rena's Abstract:

Chemical interactions between plant, pathogen, and herbivore

        A complete understanding of the interactions between the plant and its pathogenic and herbivorous pests will help to safely protect gardens and farms, securing optimal agricultural yields in the future. Plants possess a number of chemical defense mechanisms that are often induced by herbivore and/or pathogen attack. These chemical defenses can directly influence the development and survival of the pests or act indirectly by recruiting natural enemies of insect pests. Previous experiments have determined that pepper plants, Capsicum annuum, release a specific blend of volatile chemicals in response to attack by Xanthomonas campestris pv. vesicatoria bacterial infection. However, further experiments need to be conducted to understand the dynamics of plant volatile production in response to these organisms, and to determine if such volatiles are a product of the plant's active defense against the attacking pest.

        The objectives of my research were first, to study the effect of three concentrations (108, 104, and 102 cfu/mL) of Xanthomonas bacteria on the volatile emission by pepper plants. I found that plants released more volatiles in response to increasing amounts of bacterial inoculum. Second, I wanted to examine the effect of bacterial infection on the feeding preference of Spodoptera exigua, beet armyworm (BAW). Results from my experiment suggest that, in a dual-choice situation, BAW may prefer the infected pepper leaves to healthy counterparts.

        The identification of pathogen and herbivore induced plant volatiles and knowledge of their effect on the biology and behavior of pathogens and herbivores will greatly contribute to the development and improvement of environmentally sound methods for control of the pests. The data obtained from my study adds to the better understanding of the interactions between pepper plants, the bacterial leaf spot pathogen, and BAW. Additionally, the information obtained from my project provides the basis for the determination of thresholds for disease detection and defense activation. It is hoped that in the future, the data collected from other experiments like this will help in the enhancement of naturally produced chemical defenses in plants against pathogens and other pests.

 

Richard Mankin, Mentor

Brett Miller using the DAVIS program to analyze acoustic signals generated by rice weevil larvae in wheat grain.

Brett Miller's project involved the acoustic detection of insects (rice weevil and Indian meal moth larvae) infesting stored products (wheat grain and dog food).  He was testing the hypothesis that electrical stimulation from a high voltage prod would encourage insect activity (i.e., movement or feeding).  Increasing the level of activity makes the insects easier to detect by acoustic sensors.

Using the AED-2000 to detect acoustic signals from infested wheat in CMAVE's anechoic chamber.

Wheat grain undergoing electrical stimulation.

Ol' Roy Dinner Rounds undergoing electrical stimulation.

Brett's Abstract:

Effects of Electrical Stimulation on Activity Levels in Plodia interpunctella and Sitophilus oryzae

Plodia interpuntella, more commonly known as the Indian meal moth, is one of the most common pests infesting stored products. It is also one of the most troublesome, as the larvae can feed on a large variety of foods ranging from wheat to chocolate, but especially birdseed and dry dog food. The female moth will lay anywhere from 40 to 400 eggs. Infestations are usually characterized by the presence of adult moths and silken threads spun by the larvae. The meal moth is a big problem for companies which store their packaged food products in warehouses where unsanitary conditions can easily lead to infestations. These infestations then cause damage to food products as well as company reputation if the infested goods are not found and disposed of before they reach the consumer. The current solution to this problem is to randomly select different packages from various locations of the warehouse or storage facility and open them to see if they contain any contaminated material. However, there is still the possibility that infested goods may go undetected, and the ones that are found and destroyed result in a loss of revenue. A better solution to the problem is to listen for sounds that the larvae produce when they are feeding, or moving around in the food. This is done with highly sensitive acoustical sensors that are connected to headphones or a computer equipped with an oscilloscope. The problem with this is that the insects don't always make noise. The president of Hot-Shot Products Co., Bill Bartel, Sr., thought that the electricity produced by the livestock prods his company manufactures might be a means of increasing insect activity, making it easier to detect the insects through the use of acoustical sensors. This project was designed to test this idea. Preliminary tests were conducted on rice weevil (Sitophilus oryzae) larvae but showed no consistent results, so the meal moth became the next test subject. Larvae between the ages of seven and nine days were allowed to infest individual pieces of dry dog food (one larva per piece). Each piece was inspected for activity using a piezo sensor until a piece containing an active larva was found. Then two electrodes fashioned from paperclips were inserted into the dog food, and the dog food was placed on the sensor for recording. The output was recorded for three minutes, then the food was prodded with several short bursts of electricity from the Hot Shot livestock prod. Immediately after this, three more minutes of sound data were recorded and a timer was set for ten minutes. When ten minutes had passed, another three minutes were recorded to see if the activity had dropped off after the initial stimulation. Three sets of twenty tests were done this way. After analyzing with a computer signal analysis program and reviewing the results, it was found that activity levels were generally higher after prodding than before. As a control for effects of handling, another three sets of twenty tests were performed in the same manner, except the electricity was replaced with slight agitation. After analyzing these tests, no consistent increase in activity after agitation was found.

 

David Oi, Mentor

Charles Fletcher removing a colony of Argentine ants.

During the summer Charles Fletcher conducted solid and liquid bait attractancy tests for six types of baits, on both carpenter ants and Argentine ants.

Examining a colony of Argentine ants.

Charles' Abstract:

Attractants Test for the Florida carpenter ant & Argentine ant

A test was conducted with granular and liquid ant attractants, to determine which attractant would be fed on the most by the Florida carpenter ant, Camponotus floridanus. For the granular attractants, a proprietary ICF ant bait was preferred with 33% of the ants feeding on it. The Multiple Species Ant Attractant was preferred among the liquid attractants, with 24% of the ants feeding on it.

For a second project, the objective was to examine the effect of rearing diet on bait feeding preference by the Argentine ant, Linepithema humile. Colonies of Argentine ants were reared on either 10% sugar water or corn syrup for two weeks. For the colonies which were fed 10% sugar water, 51% of the ants fed upon the 25% sugar water, while 35% fed upon 10% sugar water and 14% fed upon corn syrup. For the colonies which were fed corn syrup, 55% of the ants fed upon the 25% sugar water, while 34% fed upon 10% sugar water and 10% fed upon the corn syrup. The rearing diet did not have an effect on the feeding preference among baits in this study.

 

Don Silhacek, Mentor

Kimberly Bass is testing the hypothesis that the Indian meal moth (Plodia interpunctella) is attracted to some volatile emanating from the plywood in pallets used in warehouses storing commodity.

Counting Indian meal moth larvae in test samples.

Kimberly's abstract:

The Attractants of Plodia interpunctella

Plodia interpunctella, otherwise known as the Indian meal moth, is the number one pest of stored food products in the United States. Each year the United States loses millions of dollars in revenue from these moths infesting grain and finished flour products. Last summer the observation was made that Indian meal moths were attracted to plywood pallets even if there was no commodity on the pallet. My project was to find out why this was happening. It was hypothesized that a volatile in plywood attracted the moths to the empty pallets that were commonly used in our test warehouses. In this project it was found that this hypothesis was not true. The results obtained show that plywood has no attractive volatile. We then hypothesized that the color of the pallet might be involved. In tests just concluded, we did indeed find that adult moths were attracted to the color brown. Further study is needed to understand all the factors involved in moth attraction and determine if more than the one color is attractive.

 

David Williams, Mentor

Dwayne McKnight is making observations on imported fire ant workers that have been exposed to natural oils in the small cups.

Dwayne McKnight's project examined how natural oils in the diet affect feeding behavior and survival of red imported fire ants (Solenopsis invicta). He is evaluating how effective these natural products are for possible use in baits to control fire ants.

The cups in the photo contain the ants and the natural oils that have been mixed in an attractive substance (sugar-water).

Dwayne's Abstract:

Evaluation of Natural Products Against the Fire Ant

A laboratory study was conducted to evaluate natural products for use in baits against the red imported fire ant, Solenopsis invicta. The following natural products were tested: myrrh, camphor oil, rosemary oil, oregano oil, geranium oil, basil oil, anise oil, clove oil, pine needle oil, and the control was soy bean oil. Myrrh at a 20% concentration and all other products at a 5% concentration killed between 70 and 100% within the first 4 days. Because of fast, high mortality in trial 1, a second test was conducted with lower concentrations.

Myrrh at a concentration of 10%, oils of camphor, rosemary and oregano each at a concentration of 1%, and all other products at a 5% concentration killed between 30 and 100% the first 4 days. Pine needle and basil oils caused the greatest kill exhibiting 99% kill by the sixth day. These products did not exhibit delayed mortality, which is desirable in an ant bait.

 

Jerry Hogsette, Mentor

Alyce NeJame was involved in two projects this summer. The first involved testing of solid baits used to combat house flies. The tests were conducted in aluminum screen cages (above) with baits composed of varying ratios of boric acid and sugar.

The solid bait containers.

Alyce's second project examined the effectiveness of a new trap for flies and mosquitos, called the BugJammer. This device produces the sound of a beating heart (dog or human), and may emit carbon dioxide, heat, or light, depending on the model.

The BugJammer unit with stable flies and house flies stuck to the adhesive cap insert.

Alyce's abstract:

Efficacy of Boric Acid Granular Baits on Musca domestica

The efficacy of boric acid granular baits was tested in this experiment. Concentrations ranging from 3% to 33% were tested. The hypothesis was that the 9% concentration would be the most effective to produce 50% mortality in the least amount of time. This assumption was made based on last year's experimentation where the 8% concentration of boric acid bait worked the best. Probit analysis showed that the LD50 (lethal dose to kill 50 percent of the population) was essentially 9%, based on the data collected.

The baits were mixed in a liquid form and then freeze dried. The experiment was set up with 7 standard (35 x 45 x 35 cm high) fly cages with 25 female house flies (Musca domestica L.), 5 to 6 days old and starved for 4 hours, in each. A 150 ml beaker containing 140 ml of water was placed in the front left corner of each cage. The bait was weighed out at approximately 1 g per concentration, placed in aluminum weigh boats, and placed in the rear right corner of the cages. The flies were released and mortality was recorded at 24, 48, 72 and 96 hours after release time.

The results were not as predicted in the hypothesis. After analysis by probit analysis (SAS), the LD50 was shown to be ~14 percent boric acid. The concentration tested that was closest to the LD50 was 17 percent. Therefore, this was the concentration used to calculate the LT50, which was ~53 hours.

Continuing research is being planned with several tests to determine if color or scent has a positive effect on the efficacy of the baits. Also, is there a level at which the boric acid concentration becomes repellent to the flies? Currently, data are being collected on how long the flies have to be exposed to the bait.

 

Terry Arbogast, Mentor

Melanie Gray is using the Surfer program to analyze data on cigarette beetles (Lasioderma serricorne).

In the environmental growth chamber, Melanie is examining almond moth (Cadra cantella) pupae.  This project involves determining how well almond moths do on various diets.

Melanie's Abstract:

Cigarette Beetle: Analysis of Spatial Distribution of Lasioderma serricorne (F.)

The Cigarette beetle, Lasioderma serricorne (Fabricius), is a common pest in homes, stores and warehouses. As the name indicates, this beetle is found in tobacco products such as cigarettes, cigars and even chewing tobacco, but it also attacks a variety of products found in your pantry, such as flour, spices and cereal. Due to the large number of eggs produced and the wide range of products susceptible to infestation, the cigarette beetle may be difficult to control. The first indication of its presence is often adults flying around lights at night. The best way to control an infestation of the cigarette beetle is to find the source and dispose of infested items. Then clean the area well, using a vacuum cleaner. The vacuum cleaner bag should be thrown away to prevent another infestation.

Experiments aimed at monitoring the beetles in large warehouses and retail stores have shown that pheromone traps and spatial analysis of trap data are effective in identifying the areas of infestation. A model of these large-scale experiments was set up in a metal storage shed at CMAVE. The purpose of the project was to evaluate how accurately contour analysis methods pinpoint centers of beetle infestation. In this experiment we released two-thousand beetles in the shed, and recorded the number of beetles in each of the fourteen pheromone traps after 6, 24 and 48 hours. Throughout the experiment we also measured temperature (°C) at all trap positions and relative humidity at some. The experiment was replicated 5 times over a five-week period.

The temperature, humidity and trap catch data were entered in Surfer 7 for contour analysis. By comparing contour maps of temperature and humidity with contour maps of trap count we were able to see how these environmental factors affected the number of beetles caught in the traps. These analyses, in which the source of infestation was known, will help us to better interpret analyses for commercial situations. By precisely locating infested areas, treatment can be targeted precisely where needed to rid a warehouse, store, or home of this pest. This eliminates the need to treat an entire building, and thus reduces pesticide risk.

 

Don Silhacek, Mentor

Laura Parenteau's work examined the effect of diet on growth and survival of Indian meal moths (Plodia interpunctella). Here she is preparing the Plodia diet.

Counting the larvae and pupae of Plodia moths.

 

Prem Chourey, Mentor

Ranyelle Craig is preparing the buffer used to rupture the maize cells from which nucleic acids are extracted.

Preparing agarose gel, which will be used in resolving mixtures of DNA fragments.

Preparing a sample for the spectrophotometer.

Ranyelle's Abstract:

Genetic Cloning: A Scientific Process

The main objective of my research at the Crop Genetics & Environmental Research Unit, CMAVE, Gainesville, Florida, was to gain hands-on training and experience with a few essential techniques that are routinely applied in Plant Molecular Biology research. More specifically, I isolated deoxyribonucleic acid (DNA) from Escherichia coli (E. coli) and genomic DNA from etiolated Zea mays shoots. I also isolated ribonucleic acid (RNA) from maize suspension-cultured cells. I was able to quantitate the nucleic acids using a spectrophotometer with an absorbency of 260 AU. I used agarose gel electrophoresis to assess the quality of the nucleic acids. The RNA extracted was used to perform a reverse transcription, which uses an RNA template to generate single-stranded DNA molecules complementary to RNA (cDNA). Subsequently, a polymerase chain reaction was applied, amplifying the cDNA exponentially through cycles of denaturation, annealing and extension. This method, more commonly referred to as RT-PCR, allowed the successful partial cloning of a Sucrose Synthase gene.

 

Rui-de Xue and Donald R. Barnard, Mentors

Andrew Kao is dissecting Aedes albopictus mosquitos to count the eggs.  He is learning how sublethal levels of a toxin affect behavior and fecundity.

Using a suction tube to capture mosquitos from a cage.

Andrew's Abstract:

Effect of low doses of toxic baits on host-seeking, blood feeding, and fecundity in Aedes albopictus

        Mosquitoes pose problems to humans and animals as a vector for disease transmission. Liquid formulations of toxic baits have been used to kill adult mosquitoes. However, intake doses vary from mosquito to mosquito and do not always result in the death of the mosquito. In such situations, it would be of interest to examine the effects of low doses of toxic baits on host seeking, blood feeding, and fecundity in mosquitoes. The information from this study could be used to understand the potential for controlling mosquitoes using low doses of toxic baits and to reduce pesticide application for mosquito control. The experiment was conducted with adult female Aedes albopictus and divided into two parts. The first examined the host seeking and blood feeding behavior of Aedes albopictus and the second explored whether or not fecundity was affected. Female Ae. albopictus were separated into treatment and control groups where the treatment groups received 0.1% of the toxic baits. To test host seeking, treatment groups and control groups of 100 females each were placed in an olfactometer with a human hand as an attractant. To examine blood-feeding behavior, individual female mosquitoes were placed in clear plastic feeding cages and allowed to feed on a guinea pig. Fecundity effects were compared by blood-feeding both the treatment and control groups, and then they were held in the laboratory condition (25°C and 14L:10D). Seventy-two hours after blood feeding, mosquitoes were dissected and examined for egg abundance and development. Blood-engorged females were allowed to lay eggs and the number of eggs was compared between treatment and control groups. In these experiments it was found that the toxic baits at low dose application did affect host-seeking and blood-feeding behaviors. In the host-seeking test, 26% of the control mosquitoes were attracted to the human hands within 3 min exposure, while only 11% of the treatment group females were attracted. Blood feeding tests showed that only 12% of the control group did not feed in the allotted time, whereas 52% of the treatment group refused to feed. The fecundity tests showed that female mosquitoes in control groups yielded 9.5- 20 times eggs more than in treatment groups. Dissected mosquitoes from the control groups showed IV-V stage of follicular development after 72 hours, while treatment mosquitoes showed II-III stage of development. The experiments showed that the low doses of toxic baits affect host seeking and blood feeding behavior in Aedes albopictus, and reduced fecundity.

 

Jesusa Legaspi, Mentor

Christy Copeland is learning about beneficial and pest insects in vegetable crops at the Florida A&M University (FAMU) Research and Extension Center in Quincy, FL.

Enjoying a field tour of a demonstration vegetable plot at FAMU, Quincy, FL.

Christy's abstract:

        The objective of this project was to cultivate wild and domesticated colonies of Podisus in order to observe their growth patterns. A primary observation was made that suggested that the wild colony was not growing as well in the given conditions as the domesticated colony. For wild Podisus, the death rate was higher and the birth rate was lower. From this observation, several inferences were made. The environment in which the colonies were cultivated was probably more conducive for domestic colony growth than wild colony growth. Environmental factors that were recognized as being possible sources of this observation were space and temperature. The surroundings created had limited space and a relatively constant temperature. It is known that wild Podisus are accustomed to a great deal of space and varied temperatures, both of which were not there.

 

Robert Meagher, Mentor

Felicia Haynes' project objective was to determine the fecundity of the fall army worm in relation to diet and mating schedule.

Counting eggs on a tape.

 

Eric Schmelz, Mentor

Erica Simbro's project seeks to better understand insect-induced plant signaling pathways involved in the stimulation of both volatile and non-volatile defenses in corn.  She is studying whether different plant defenses, which reduce insect growth rates and attract natural enemies, are regulated by the same stimuli and plant signals.

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

 

Supervised by Al Handler

Dorel Humphrey removing adult fruit flies (Drosophila) from the incubator.

Dorel Humphrey worked on a Drosophila germline transformation project using the piggybac transposable element.

The fruit flies are placed in these vials for later examination under the flouresent stereoscope.

 

Supervised by Bob Vander Meer

Jakeisha Robinson worked on a project involving the biological control of imported fire ants. Here she is tending a colony.

Watering the ants.

 

Supervised by Ray Kerr

Ernest Jackson is a Santa Fe student who arrived at CMAVE last year through the YES program. He is now working as an assistant in the safety office, performing weekly inspections of the facilities, among other duties.

Examining the books to identify missing Material Safety Data Sheets (MSDS).

 

Supervised by Dianne Underwood

Mwitse Ansoanuur compiling a list of static IP numbers being used on the CMAVE computer network.

Mwitse Ansoanuur's major duties this summer involved setting up new user accounts on the local area network, installing software applications (i.e. Norton Antivirus, Exchange mail), and setting up client computers. He also helped to troubleshoot network, email, and other computer problems.

Assembling the network servers in the new computer room.

 

Don Silhacek, Mentor

Rose Mikulski's study focused on the Indian meal moth (Plodia interpunctella). She sought to determine which diets females are most attracted to for egg-laying.

Counting larvae found on ground dog food.

 

Richard Mankin, Mentor

Jeffrey Barrientos using a rubber suction tube to selectively remove female Carribbean fruit flies from the screen cage, and place them in the temporary holding jar on his left.

Jeffrey's project examined what effect the song of the male Caribbean fruit fly (Anastrepha suspensa) would have on female Caribbean fruit fly behavior.  Specifically, he examined the hypothesis that acoustic playback of the male's song, directed through a funnel toward an artificial leaf, would increase the time spent by females on the leaf.  A video camera and recorder were used to record the time spent on the leaf both with and without the sound playback.  The results of this study could aid in the development of new ways to lure and trap fruit flies in the wild.

Releasing the captured flies into a cage of females only.

The video setup used by Jeffrey in one of the sound insulated chambers at CMAVE.  Sound of the male Caribfly is played through the black funnel at the back of the cage, while the artificial leaf near its opening is videotaped.

Closeup view of the white paper 'leaf' with the funnel directing male Caribfly song toward it.

 

Bob Vander Meer, Mentor

Pooja Gupta placing fire ants in vials.

Pooja Gupta's project examined the effects of alarm pheremones on different species of fire ants.  She also studied how the phorid fly, the ants' natural predator, reacts to the presence of the ant species' alarm pheremones.

"New and improved" fire ant vial.  Order now...

 

Steve Ferkovich, Mentor

Brandon Verblow examined the effect of a pollen diet on the fecundity of the insidious flour bug (Orius insidiosus).

Counting eggs on beans under the dissecting microscope.

 

Steve Ferkovich, Mentor

Ann Joseph studied how altering the smell of artificial diet will affect its attractiveness to the insidious flour bug (Orius insidiosus).

At the incubator.