Browsing by Subject "Solenopsis invicta"
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Item A faunistic survey of the organisms associated with ant colonies of West Texas (especially Solenopsis spp.)(Texas Tech University, 1980-12) Neece, Kenneth CharlesNot availableItem A survey for pathogens associated with the ants of West Texas (especially the Solenopsis spp.)(Texas Tech University, 1980-05) Beckham, Richard D.Representative samples of 113 different ant species from west Texas (west of the l00th Meridian) were examined for the occurrence of indigenous pathogens. Samples of the red imported fire ant, Solenopsis invicta Buren, taken from the south central and south eastern part of Texas were also examined for indigenous pathogens. This survey was conducted to lay the groundwork studying the possible suppression by pathogens of the red imported fire ant in its westward movement. Samples were taken at 404 locations throughout the study areas. In the examination of 2,525 samples for the presence of bacteria, viruses, fungi and protozoa, only an occasional occurrence of a pathogen was detected. It appears that the potential for using pathogens presently associated with ant species to inhibit the westward migration of the red imported fire ant is small and that alternate methods of control must be investigated.Item Alginate pellet formulation of Beauveria bassinana pathogenic to the red imported fire ant(Texas Tech University, 1995-12) White, Hershel E,Not availableItem An assessment of programming needs among county agents in red imported fire ant quarantined counties in Texas(Texas Tech University, 2002-12) Harman, Amanda JoThe purpose of this study was to provide an accurate assessment of the Texas Cooperative Extension educational programming efforts as it relates to red imported fire ant control. One hundred twenty members of the Texas Cooperative Extension were surveyed using the bimodal survey model. This model uses a combination of e-mail and paper contacts to encourage respondents to answer an online or paper questionnaire. An overall response rate of 80% resulted from the use of the 25-day model. Twenty-five of the respondents have attended more than 4 fire ant training sessions, while 30 have had no training. Thirty-seven percent ranked themselves of knowing a little more than a novice when asked about fire ant biology, 47.7% ranked themselves as somewhat an expert. The majority of the participants consider RIFA to be a major problem in the next 10 years. When asked about the products currently available for red imported fire ant control, the majority of the participants thought that the products worked most of the time. Broadcast bait, the Texas Two-Step Method and mound treatments were considered somewhat effective by the participants. The majority of the participants have conducted more than four fire ant programs with the help of the Internet, Texas A&M Website, extension publications, newsletters, "Spring Fling" media kit, the Fire Ant Awareness Week packets, fact sheets, fellow Aghcultural agents, Integrated Pest Management agents, and other state specialists. This study also determined that fact sheets, news releases, Power Point® presentations, kits and information of organizations would be the most useful for future red imported fire ant programming.Item cDNA cloning and transcriptional regulation of the vitellogenin receptor from the imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae)(Texas A&M University, 2005-02-17) Chen, Mei-ErReceptors that transport vitellogenin into oocytes are of vital importance to egg-laying species because they promote oocyte development. In this study, we describe the cloning of the first hymenopteran vitellogenin receptor (VgR) cDNA. Using reverse transcription polymerase chain reaction (RT-PCR) and both 5?- and 3?- rapid amplification of cDNA ends (RACE), cDNA fragments encompassing the entire coding region of a putative VgR from fire ant (= SiVgR) were cloned and sequenced. The complete SiVgR cDNA has a length of 5764 bp encoding a 1782-residue protein with a predicted molecular mass of 201.3 kDa. The deduced amino acid sequence of the SiVgR revealed that it encoded a protein belonging to the low-density lipoprotein receptor superfamily. The number and arrangement of modular domains of SiVgR are the same as those of mosquito and fruit fly VgRs, except there are only four Class A cysteine-rich repeats in the first ligand binding domain of SiVgR compared to five in the mosquito and fruit fly. The deduced amino acid sequence of the SiVgR exhibited 35% and 31% identity to those of the mosquito and fruit fly VgRs, respectively. Northern blot analysis demonstrated that the 7.4-kb SiVgR mRNA was present only in Northern blot analysis demonstrated that the 7.4-kb SiVgR mRNA was present only in ovaries of reproductive females − both alates (virgins) and queens (mated) and was more abundant in alates. The developmental profile of transcriptional expression was determined by semiquantitative RT-PCR. It showed that the SiVgR transcript increased 6-fold from 0- to 10-days after mating, then remained constant through 30 days. It also showed that the SiVgR transcripts increased with age in alate virgin females. The transcriptional expression of the SiVgR was up-regulated more than two-fold by methoprene, a juvenile hormone analog, as determined by using an in vitro system. This suggested the SiVgR gene is JH regulated.Item Comparison of desiccation resistance among three species of fire ants (Hymenoptera, formicidae, solenopsis) from Texas(Texas Tech University, 1988-05) Munroe, Paul DavidNot availableItem Digital image processing and spatial frequency analysis of Texas roadway environment(Texas Tech University, 1999-12) Tang, ZhenA report presented on the acquisition, storage, processing and analysis of digital images of both fireants activities and small target visibility, beginning with the general introduction of background knowledge in digital image representation, covering acquisition, storage, enhancement and finally development of methods to extract information of interest from the digital images. Fast Fourier transform and digital image processing techniques are reviewed and utilized.Item Effect of red imported fire ants on reproduction, health, and survival of northern bobwhites(Texas Tech University, 1999-08) Mueller, James MichaelThe red imported fire ant affects northern bobwhite by killing pipping chicks (Mitchell 1989) and altering activity of young chicks Pedersen et al. 1996). In addition, the red imported fire ant may dramatically alter the abundance of invertebrates, an important component of northem bobwhite diets, when it colonizes an area (Porter and Savignano 1990). However, there is no evidence northem bobwhite populations are significantly impacted by these particular effects. The red imported fire ant could affect northem bobwhite populations through other means, such as by altering growth or reproduction of northem bobwhite through physiological effects of envenomation. This study evaluated potential mechanisms by which red imported fire ants impact northern bobwhite reproduction, survival, and health. The objectives were to determine the effects of red imported fire ants on hatching success, growth, immunocompetence, and survival of northern bobwhite chicks.Item Effect of Solenopsis invicta buren territoriality on native ants of central Texas(Texas Tech University, 1985-08) Claborn, David MNot availableItem Effects of static electrical devices on red imported fire ant behavior(Texas Tech University, 1998-12) Ipser, Reid MatthewNot availableItem Feeding, clutch sizes, and the population dynamics of the Texas horned lizard, Phrynosoma cornutum(Texas Tech University, 2000-05) Fagan, Jesse F.This thesis includes the development of a population dynamics model on the Texas Horned Lizard and in addition, a prey model involving interaction between the Texas Horned Lizard's main food source, harvester ants, and the non-native fire ant. The goal of this work is to understand the population dynamics of the Texas Horned Lizard, the horned lizard's relationship with its prey, and the effects of fire ants on the biological complexity of this population.Item Fire ant dispersal along Texas highways(Texas Tech University, 1998-05) Russell, Scott A.All organisms require specific resources for growth and reproduction. Favorable environments lead to positive population growth and, eventually, to depletion of limited resources. This depletion creates the need for dispersal to relieve crowding and to provide access to new resources. Dispersal can, therefore, be for the purpose of locating necessary resources; e.g., food, mates, shelter, or oviposition sites. Price (1984) described populations as not just increasing or decreasing in numbers, but also moving from place to place and expanding and contracting. Dispersal is adaptive, permitting individuals to escape crowding and colonize new habitats. Organisms must be capable of dispersal to new habitats, and active dispersal requires energy to walk, swim, or fly to a new habitat Passive dispersal does not require energy but does require favorable environmental conditions (wind, water, host). Available habitats require that organisms have access to the habitats, and space or other resources must be available to the immigrant organism. However, the overall geographic range of an organism is seldom one continuum of habitat. Organisms tend to avoid unfavorable habitats; therefore, populations of some organisms may be found in clumps of favorable habitat but may be absent from the vast majority of its habitable range. Haas (1995) found that robins and tlirasbes, for example, traveled along wooded draws connecting planted windbrealcs as if the draws were stepping stones b>etween the windbreaks. The likelihood was greater that birds would disperse between habitats when habitats were connected by a wooded draw.Item Foraging and recruitment abilities of Solenopsis invicta Buren, compared with other ant species indigenous to Texas(Texas Tech University, 1985-05) Jones, Stanley RSince its accidental introduction into Mobile, Alabama, the red imported fire ant, Solenopsis invlcta Buren, has become an economic pest of much of the southern United States. Each year this ant continues to expand its range. Why S. invicta is able to successfully colonize areas previously inhabited by multifarious ant species is not understood. Possible explanations include its aggressive behavior, large colony size, and foraging efficiency. This study was conducted to compare the foraging efficiency of S. invicta to three ant species native to south central Texas. Native ants studied include Pheidole dentata Mayr, Monomorium minimum (Buckley) , and Forelius foetidus (Buckley) . Temporal recruitment and food retrieval patterns were recorded and compared for all four species held at equal colony strengths. Results indicate that interspecific differences in recruitment patterns do occur. However, these differences are subtle and do not suggest that S. invicta is a more efficient forager under laboratory conditions, than the other three species.Item Host/parasite interactions between Solenopsis invicta (Hymenoptera: Formicidae) and Thelohania solenopsae (Microsporida: Thelohaniidae)(Texas A&M University, 2007-09-17) Hale, Michael WalkerThelohania solenopsae Knell, Allen and Hazard is a microsporidian pathogen that infects the red imported fire ant Solenopsis invicta Buren. This five part study examined the effects that T. solenopsae has on constructs of colony fitness in field mounds and adoption rates, how T. solenopsae spores are affected by different stable temperatures. This study also examined the effects on T. solenopsae spores due to centrifugation out of the host cell, pH of the solution the spores are kept, and food classes that could be ingested by S. invicta. For the first study, a total of 29 colonies were collected, 16 infected, and 13 uninfected. The study concluded significantly lower brood production in uninfected field colonies when compared to infected field colonies. Additionally, the total number of queens per colony is significantly greater in T. solenopsae infected mounds with 35.4????31.9 queens for infected mounds and 15.5????11.2 queens for uninfected mounds, demonstrating a possible host response to parasite infection. In the study examining stable temperature effects on T. solenopsae spore growth and spore type, a stable temperature of 31????C induced greater production of binucleate free spores in worker S. invicta. There was an overall decrease of T. solenopsae octospores at 16????C, 26????C and 31????C. The studies concerning extraction of T. solenopsae spores, and inclusion in food infusions demonstrated viable spore recovery after centrifugation, verified by using Calcofluor M2R and Sytox Green dual staining. This study demonstrated significant decreases in spore viability over a 10 week period. The study concerning pH demonstrated significant effects of differing pH parameters with the best viable spore recovery at pH 4 and no spore recovery at pH 1 and pH 2. The least viable spore recovery occurred at pH 6 and pH 12 after 24 hours of emersion verified by using Calcofluor M2R and Sytox Green dual staining.Item Immunological response to Solenopsis invicta in cattle of different genetic types(Texas Tech University, 1999-05) Powell, Justin EldredgeThe objectives of this research were to: (1) develop bovine IgG and IgE and ovine IgG enzyme-linked immunosorbent assays (ELISA)specific to red imported fire ant venom (RIFAV), (2) estimate passive immunity to RIFAV in cattle and sheep, and (3) evaluate cattle breed differences for immune response to the red imported fire ant (RIFA). Once developed, the bovine IgG ELISA was capable of differentiating cattle (n = 23) which had been in contact with red imported fire ant (RIFA) from cattle (n = 5) that had no previous history of RIFA exposure. The optical density (OD) readings of the cows (.599 to .935 OD range) from the RIFA-endemic area as opposed to those cows (.252 to .305 OD range) with no previous exposure to RIFA and the negative control (.090) result in a P:N ratio of 10.39. The ovine IgG ELISA was also capable of distinguishing sheep (n = 9) from a RIFA endemic area from sheep (n = 10) with no history of RIFA exposure. Sheep OD means ranged from .780 (positive control) to . 113 (negative control), which results in a P:N ratio of 6.90. These results indicate that the IgG ELISA protocols can be utilized to measure IgG levels of beef cattle and sheep. However, the IgE ELISA protocol proved to be too inconsistent to use at this time.Item Impact of the red imported fire ant upon cotton arthropods(Texas A&M University, 2004-09-30) Diaz Galarraga, Rodrigo RogelioInclusion/exclusion field experiments demonstrated that the red imported fire ant, Solenopsis invicta Buren, did not affect the abundance of 49 groups of insects and spiders collected in pitfall traps. However, arthropod diversity was significantly greater (H' = 2.829) in exclusion plots relative to inclusion plots (H' = 2.763). Moreover, this study demonstrated that S. invicta can have an important impact upon cotton arthropod communities, including key predator species. Densities of ground beetles (Carabidae), spiders, lacewings (Chrysoperla spp.), and minute pirate bugs (Orius spp.) were significantly lower in the presence of S. invicta. However, populations of aphidophagous insects such as Hippodamia spp. and Scymnus spp. increased with cotton aphid (Aphis gossypii Glover) density early in the season. Abundance of cotton aphids was ca. 5x greater in inclusion plots, likely due to protection and tending by S. invicta. This increase was observed early in the season, though aphid populations did not reach economic levels. Predation of sentinel bollworm [Helicoverpa zea (Boddie)] and beet armyworm (Spodoptera exigua Hubner) eggs increased 20-30%, when S. invicta was present. Most predation of sentinel beet armyworm egg masses, measured via direct nocturnal observations, was due to S. invicta (68%) and cotton fleahopper [Pseudatomoscelis seriatus (Reuter)] (21%) in plots with S. invicta, and by the mite Abrolophus sp. (52%), spiders (13%) and minute pirate bug (13%) in plots without S. invicta. The frequencies of minute pirate bug, cotton fleahopper, S. invicta and native ants in beat bucket samples did not accurately reflect the frequency with which they were observed feeding on sentinel noctuid eggs. Overall, the results of these studies demonstrated that S. invicta was associated with declines in the abundances of minute pirate bug, spiders, and lacewing and with an increment in cotton aphid populations, though they did not reach the economic threshold. Moreover, S. invicta significantly increased predation of bollworm and beet armyworm eggs. All together, the results suggested that S. invicta has a net positive impact on cotton pest management.Item Implications of Relative Ant Abundance and Diversity for the Management of Solenopsis Invicta Buren with Broadcast Baits(2009-05-15) Calixto, Alejandro AntonioHigher densities of S. invicta in the United States relative to South America are explained mainly by the absence of natural enemies and low interspecific competition (IC). Despite advances in S. invicta management, broadcast insecticide baits remain as the primary tool for effective control. I studied interspecific interactions of ants and the use of baits on the management of S. invicta to test the following hypotheses: 1) relative abundance of native ants increases ~25% for bait treated sites compared to untreated, 2) behavioral dominance by S. invicta decreases ~10% in bait treated sites compared to untreated, and, 3) foraging by S. invicta on insecticide baits is higher ~10% in low native ant densities areas compared to high densities. Experiments were conducted on three sites with different densities of native ants (low, medium, high), but with similar densities of S. invicta. An enhanced BACI (Before/After-Control/Impact) design was used. Experimental units consisted of 0.4 ha plots. Three treatments were randomly assigned to units and replicated four times; 1) Slow acting bait, 2) Fast acting bait, 3) Untreated Control. Samples and observations were collected for several weeks before/after the treatments to account for temporal variation and to determine rates of reinvasion. Ants were monitored using pitfalls and food lures. Interspecific competition was determined by applying placebo bait. Results indicate that different management methods did not impact resident ants when they are at low and medium densities and that S. invicta is greatly affected; at high native ant density, competition for these baits is observed affecting both natives and S. invicta. Reinvasion of S. invicta was reduced in areas of low and medium native ant densities previously treated with baits and native ant abundance increased by ~25%. At high native ant densities, reinvasion of S. invicta was similar to Control sites. I conclude: 1) properly used, baits can help in recovery of native ant species that then compete with S. invicta; however, rote re-treatments may have a negative impact on restored populations. 2) ?bait failures? may be due to interspecific competition when initial native ant densities are high. Preliminary management considerations and recommendations are presented.Item In vitro cultivation of ovaries and ovarian tissue from the red imported fire ant, Solenopsis invicta Buren(Texas Tech University, 1983-12) Kral, Robert MardenA method for in vitro cultivation of ovaries and ovarian cells from Solenopsis invicta has been developed. Whole ovaries were kept alive, in Schneider's Dropsophila medium (pH 6.7) and Hink’s THH-FH medium (pH 6.1, 7.0), for up to six weeks without refeeding. Cells from physically and chemically dissociated ovaries were kept alive for up to 15 days. Very little evidence of mitosis was observed in cell cultures. TNM-FH, pH 7.0, supported cell cultures which were superior to those obtained in the other tested media. The addition of fetal bovine serum, bovine serum albumin, chick embryo extract, whole egg ultra filtrate, and glycylhistidyl-lysine to this medium did not induce growth or longevity greater than that observed in control media, which contained only fetal bovine serum. Overnight refrigeration of whole ovaries in 0.5 mg/ml collagenase solution, followed by 60 minutes incubation at 28o C and physical dissociation, gave a cell yield which was superior to that obtained by other methods of tissue disruption.Item Invasive interactions of Monomorium minimum (Hymenoptera: Formicidae) and Solenopsis invicta (Hymenoptera: Formicidae) infected with Thelohania solenopsae (Microsporida: Thelohaniidae)(Texas A&M University, 2006-08-16) Keck, Molly ElizabethThelohania solenopsae Knell, Alan, and Hazard is an internal microsporidian that parasitizes the red imported fire ant, Solenopsis invicta Buren. This experiment studied the invasive interactions between the native United States ant, Monomorium minimum (Buckley), and S. invicta colonies infected with T. solenopsae and S. invicta colonies free of parasites. This study utilized S. invicta colonies of 100, 300, 600, 800, and 1000 workers to determine the ability of 1000 M. minimum workers to invade each S. invicta colony size. There was a significant difference in the time for M. minimum to invade S. invicta when comparing S. invicta colonies of 1000 workers infected with T. solenopsae to S. invicta colonies that were uninfected. It was also determined that there was a significant difference in the time for M. minimum to invade smaller uninfected S. invicta colonies as opposed to larger uninfected S. invicta colonies. There was no significant difference in the ability of M. minimum to invade smaller S. invicta colonies infected with T. solenopsae as opposed to larger infected S. invicta colonies. It was therefore concluded that S. invicta colonies infected with T. solenopsae were not able to defend their colony or prevent competing ants from invading as well as uninfected S. invicta colonies. This study also demonstrated that M. minimum is a significantly more invasive species when compared to S. invicta, invading S. invicta territories in every situation and doing so in a significantly shorter period of time than S. invicta colonies invaded M. minimum colonies.Item Investigations of cattle grazing behavior and effects of the red imported fire ant(Texas Tech University, 2003-12) Austin, Galen P.The purpose of this research was to study the effects of the Solenopsis invicta Buren; Hymenoptera: Formicidae, the red imported fire ant (RIFA) on Texas livestock and was funded by the Texas Fire Ant Initiative. This research was multipurpose in nature, and several different aspects of RIFA and their effects on livestock were studied. Additionally a Global Positioning System (GPS) was designed and fabricated in order to conduct a portion of the research. The initial phase of this research was to evaluate recruitment of RIFA to various livestock feeds. Recruitment was investigated in three areas of Texas with one site in Taylor, Smith, and McLennan counties. Feeds evaluated were a commercial cat food (CAT), previously used by researchers for RIFA recruitment, a calf starter feed, a horse and mule feed, a cow range cube, cottonseed meal, and extruded whole cottonseed (EWC). One-gram samples of each feed were placed into plastic bait cups. At each study, site bait cups were placed in a 6 x 6 Latin square arrangement with two cups of each feed placed on their sides. Bait cups were recovered after 15 and 30 min. After all cups were collected, each site was evaluated for RIFA mound density. To approximate a normal distribution, the natural log of RIFA count per cup was the dependent variable. Data were analyzed through analyses of variance where feed, pasture, feed x pasture, row within pasture, and column within pasture were independent variables. Row within pasture was used as the error term to test pasture differences. Differences were observed for feed (P < 0.001), pasture (P < 0.001), and feed x pasture {P < 0.05) for ant count after 15 (AC15) and 30 min (AC30). Cat food had the highest least squares mean AC15 per cup in four of seven pastures (2.28 to 3.92), and EWC had highest AC15 in the other three (2.56 to 4.00). Extruded whole cottonseed had the highest AC30 in five of seven pastures (4.06 to 5.40), and CAT had the highest count in two pastures (2.64 and 3.14). Across all pastures, for AC15, CAT had higher {P = 0.0197) RIFA recruitment than did EWC (3.14 and 2.67, respectively), with others ranging from 0.86 tol.71 ants per cup. For AC30, EWC averaged 3.79, CAT averaged 3.64 and the rest ranged from 0.96 to 2.32. All pastures had higher ant counts at 30 versus 15 min except two. Ant count after 15 min per pasture ranged from 1.00 to 2.78, whereas AC30 per pasture ranged from 0.69 to 3.09. Density of RIFA mounds across pastures ranged from 395 tol,220/ha, but did not match exactly with AC15 or AC30. To evaluate the grazing behavior of beef cattle in pastures infested with RIFA, a cattle-tracking GPS collar was developed. The GPS collar was developed as a means to monitor the grazing behavior of cattle within RIFA-infested pastures. Although commercial GPS tracking collars were available at the time of the development of the GPS collars, the cost of $3,000 to $5,000 per collar was prohibitive. In addition, the GPS collars developed provided real-time GPS position data reporting to a computer in a remote location where the position data were stored. Commercially available GPS collars stored position data on board that had to be downloaded once the collar had been retrieved from the animal and were limited by the amount of on-board memory for GPS data storage. AU RIFA research in the final phase was conducted at the Texas Agricultural Experiment Station (TAES) at McGregor in McLennan County. The objectives of this research were to evaluate the grazing behavior of beef cattle in pastures infested with RIFA. The research was conducted at the Texas Agricultural Experiment Station (TAES) at McGregor in McLennan County. The research was conducted in two phases, with Phase I occurring in July and August, 2001, and Phase II occurring in August and September, 2001. Phase I was conducted using 11 resident TAES commercial Angus cow-calf pairs that were naive to the research pastures (P5 and P6). Cow ages ranged from 9 to 14 yr. Phase II was conducted using 16 crossbred yearling steers that were naive to pastures and RIFA. To monitor the positional location of the cows and steers in both phases of the research, Global Positioning System (GPS) collars were fitted to randomly selected animals. The GPS collars used in Phase I also measured cow head movement with horizontal (HOR) and vertical (VER) motion sensors. Data from HOR and VER were summed to form a total activity (ACT) variable. Additionally both distance (m; DIS) and velocity (m/min; VEL) were calculated for Phases I and II. Chi-square x2 ) and analysis of variance tests were both employed to analyze data. In association with the x2 analysis, a Bonferroni Z simultaneous confidence interval was used to determine cattle preferences for different areas (AREA) within a pasture. Differences {P < 0.0001) were observed for cattle utilization in different areas of the pastures for both Phases I and II and were related to the primary species of forage on offer in those areas. Analysis of variance was used in the analysis of the dependent variables; HOR, VER, ACT, DIS and VEL for Phase I and DIS and VEL for Phase H. The independent variables were date, time-of-day (TOD), and AREA. In Phase I, P5, differences were observed for the TOD effect for HOR (P = 0.0292), VER (P < 0.0001), ACT {P = 0.0464), DIS {P < 0.0001), and VEL {P < 0.0001). For the AREA effect in P5 differences were observed for HOR {P < 0.0001), VER {P < 0.0001), and ACT {P = 0.0002). In Phase I, P6, differences were observed for the TOD effect for HOR {P < 0.0001), VER (P < 0.0001), ACT {P < 0.0001), DIS {P < 0.0001), and VEL {P < 0.0001). The differences observed for the AREA effect in P6 were for VER (P < 0.0001), ACT {P = 0.0003), DIS {P < 0.0001), and VEL {P = 0.0002). In Phase II, P5, differences were observed for DIS for the TOD effect {P < 0.0001) and the AREA effect {P < 0.0001). In P6, differences were observed for DIS and VEL for the TOD effect {P = 0.0312 and P < 0.0001, respectively) and for the AREA effect {P = 0.0003 and P < 0.0001, respectively).