The twospotted spider mite, Tetranychus urticae Koch, is a cosmopolitan and highly polyphagous pest of many fruits, vegetables, ornamentals, and field crops. While twospotted spider mite is a well-documented pest of corn and peanuts in eastern North Carolina, only recently has it been recognized as a consistent and serious pest of vegetables in the piedmont and mountains of North Carolina. Mites infest a number of vegetables in North Carolina including tomato, pepper, eggplant, and sweet corn, but tomato is by far the most seriously affected crop. The objectives of this study were to 1) determine the effect of vegetation on the dispersal of twospotted spider mites from tomatoes to overwintering hosts, and 2) to investigate the potential importance of various factors, including location, planting date, field history, surrounding area, pesticide use, and mite populations in surrounding vegetation, that may affect mite infestations in tomato fields in different regions of North Carolina. Two vegetation management techniques (herbicide and cultivation) plus an untreated control plot were established around senescing tomato plants. Twospotted spider mite dispersal was monitored by planting chickweed trap plants at 2, 6, and 12 m from the tomatoes. Sampling took place in the fall of 2004 & 2005 and the spring of 2005 & 2006. Only a small number of mites were collected in the 2004-2005 sampling period, making it difficult to draw conclusions. The 2005-2006 sampling period showed that herbicide-treated soil facilitated mite dispersal in the fall, while there were no differences in mite populations among treatments in the spring, suggesting a high rate of overwintering mortality. Tomato fields in the mountains and piedmont region were sampled in a grid pattern on a bimonthly basis to determine the importance of year, location, planting date, previous crop, adjacent crop, insecticide use, acaricide use, and mite populations in surrounding vegetation on mite intensities in those fields. Based on samples from 80 tomato fields, previous crop, acaricide use, insecticide use, and mite intensity in the weeds were important factors that were associated with seasonal mite intensity in tomato fields. Acaricide use and mite intensity in the weeds were important factors associated with the maximum mite intensity in tomatoes. Year, location, planting date, and acaricide use were all important factors associated with the time it took for tomato fields to reach their maximum density. Upon further analysis, it was found that none of the dependent variables (year, location, previous crop, adjacent crop, planting date, acaricide use, insecticide use) were associated with seasonal mite intensity in weeds or mite intensity in weeds on the last two sample dates. However, previous crop and insecticide use were significant factors associated with mite intensity in weeds on the first two sample dates. Furthermore, seasonal mite intensity in weeds was significantly correlated with seasonal and maximum mite intensity in tomato fields. While previous crop, current season insecticide use, and mite intensity in weeds were factors associated with mite intensities in the field, a high overwintering mortality appeared to negate the effects of these factors; consequently it was not possible to predict in advance fields that were most susceptible to high mite infestations. Acaricides will likely remain a key management strategy in the near future, and the development of sampling plans and economic thresholds will be necessary to use these materials in a judicious manner.

In contrast to many apple production areas, the phenology of the apple maggot, Rhagoletis pomonella (Walsh), is not well understood in North Carolina and other areas of the Southern Appalachian Mountains. Studies in western North Carolina in the 1970?s reported a single flight period that occurred from mid-June to mid-September, with peak fight activity occurring in late July. More recent monitoring in Henderson County, NC, showed evidence of a bimodal emergence, with the first emergence occurring in late May to early June, and the second from mid July through August. It was not clear if this represented a bimodal emergence pattern or completion of two generations. The objectives of this study were to gain a better understanding of the phenology of the apple maggot in apple-producing regions of the Southern Appalachian Mountains, to examine the post-diapause development requirements among early and late-emerging populations in North Carolina, and to determine if phenologically and geographically distinct apple maggot populations could be differentiated genetically using the COI gene of mitochondrial DNA. Apple maggot flight was monitored in abandoned apple orchards in western North Carolina and South Carolina that represented a diversity of elevations. A distinct bimodal flight pattern was observed at all locations. A second generation was also observed at lower elevations (300-330 m) in Polk County, NC, and Spartanburg County, SC. Only one generation was evident at higher elevations (>600 m) in North Carolina. Among early and late-emerging groups, the post-diapause developmental period was shorter in the early emerging groups compared to late-emerging groups. Based on sequences of the mitochondrial gene COI, no significant differences were found between early or late-emerging groups. Furthermore, analysis of the COI gene did not detect geographic isolation among populations from North Carolina, South Carolina, Massachusetts, and West Virginia, or among populations in Henderson, Polk, and McDowell Counties in North Carolina. Blueberry maggot, Rhagoletis mendax Currans, from New Jersey did not differ at the COI gene from apple maggot populations in North Carolina and South Carolina, and were most closely related to the Upward Road location in Henderson County.

The chemicals 2-tridecanone and 2-undecanone are both found naturally in the trichomes of wild tomato plants and are important in plant resistance to herbivory. 2-Undecanone recently was shown to be an effective tick repellent and is the active ingredient in the commercially available arthropod repellent, BioUD®®. The goal of this study was to examine, for the first time the, tick repellency of 2-tridecanone. Two-choice bioassays were conducted between 8% 2-tridecanone versus the repellent carrier, absolute ethanol and compared to similar choice studies with 8% 2-undecanone versus absolute ethanol. Unfed, host-seeking adult (mixed sexes) Amblyomma americanum and Dermacentor variabilis were used to evaluate repellency and time to repellent failure at room temperature on two different substrates. In filter paper assays, 2-Tridecanone was >70% repellent to A. americanum and D. variabilis for 12 and 15 h, respectively. In contrast, 2-undecanone was >70% repellent to A. americanum and D. variabilis for only 2 h. In two choice assays on cheesecloth, 2-tridecanone was 85% repellent to A. americanum for 6 h. 2-tridecanone provided repellency significantly longer than 2-undecanone. The potential use of 2-tridecanone as a tick repellent is discussed.

A three-year evaluation of crop host utilization by the tobacco budworm, Heliothis virescens (F.), was conducted from 2001 to 2003 in the central coastal plain of North Carolina. Monitoring of commercial tobacco and non-Bt cotton fields revealed spatial and temporal patterns of host use, and showed that tobacco budworm may be produced in tobacco throughout the growing season. Small plot trials conducted in 2002 and 2003 demonstrated a strong oviposition preference by tobacco budworm for tobacco when located adjacent to alternate crop hosts. The bodies of individual moths were analyzed for the presence of a cotton-specific analyte, gossypol, using high-pressure liquid chromatography?mass spectrometry/mass spectrometry (HPLC-MSMS). This technique provides a conservative estimate of tobacco budworm production on hosts other than cotton. Analysis of feral moths revealed that <10% of tobacco budworms collected in North Carolina contained gossypol. Isotope ratio mass spectrometry (IRMS) analysis of 13C/12C ratios of moths reared on four crop-plant species and two common weed species revealed a range of d13C values within that expected for plants utilizing the C3 photosynthetic pathway. Feral tobacco budworm moths collected over three years were found to have carbon isotope ratios consistent with those having fed on C3 plants. No unique carbon isotope signature was discovered that would enable a reliable determination of natal origin of feral tobacco budworm with current IRMS technology. Dose-mortality studies were conducted in 2004 to determine the susceptibility of two North Carolina strains of tobacco budworm to cypermethrin. LD50 values were 4 and 9 times greater for tobacco budworms collected in June and August respectively than for a susceptible laboratory strain. Foliar applications of pyrethroid insecticides were made to flue-cured tobacco for control of the tobacco budworm in 2001, 2002, and 2003. Pyrethroids provided significant control of tobacco budworm when compared to untreated checks in all three years of the study; however, they were generally less efficacious than the standard insecticides tested.

Loblolly pines, Pinus taeda L., are a vital part of the timber industry throughout the southern United States and are susceptible to damage and mortality as a result of attack by southern pine beetles, Dendroctonus frontalis Zimmerman. The primary defense of loblolly pines against bark beetles is constitutive resin, which provides a physical barrier to beetle colonization. A study has been conducted to determine resin production heritablity in clonal loblolly pines. Samples were taken in the spring and late summer of 2005 and 2006 in Milton, FL and Walterboro, SC. Each site included nine complete random blocks containing improved and unimproved checks and 115 and 149 sampled clones, respectively. Two resin samples were collected at breast height from each tree after resin was allowed to flow for 22 +/- 2 hours. Samples were then dried until a subset reached constant mass and sample mass data were used to determine total resin flow repeatability. Total resin flow was found to be significantly higher in one family than the improved check. Resin production by clonal loblolly pines was found to have moderately high repeatability and low positive correlation with tree volume. Results indicate that clone selection that includes resin production as well as desirable growth characteristics can result in loblolly pines that display decreased susceptibility to the southern pine beetle.

The termites (Isoptera) are an important group of eusocial insects whose breeding systems have been relatively poorly studied. In this study, we inferred the breeding systems of two sympatric species of Reticulitermes flavipes (Kollar) and R. hageni Banks by investigating colony and population genetic structure using microsatellite and mitochondrial DNA markers. Termites were collected in natural wood debris along two transects 1 km apart in a forested site in the Coastal Plain of southeastern North Carolina. Collection points within transects were at least 15 m apart (mean = 22.4 m) and each collection point was found to be a separate colony based on microsatellite genotypes. Of the total colonies collected, eight colonies were identified as R. flavipes, 28 were R. hageni and two colonies were identified as R. virginicus. A total of 720 workers from 36 collection points were genotyped at 5-8 microsatellite loci and the mtDNA haplotype was determined for two individuals from each collection point at the cytochrome oxidase II gene. Genetic analysis of family structure and comparisons of F-statistics (FIT, FIC and FCT) and the coefficient of relatedness (r) were compared with computer-simulated values revealing very similar breeding systems between the two species. Analysis using F-statistics compared with computer simulated breeding systems (Thorne et al. 1999 and Bulmer et al. 2001) suggested that nearly 90% of the colonies of both species were simple families headed by inbred monogamous pairs of reproductives while the remaining colonies were extended (inbred) families headed by low numbers of reproductives that were descendants of the founding pair, possibly their direct offspring. There was no evidence of genetic differences between transects based on microsatellite data for R. flavipes (FST = 0.044, 95% confidence interval (CI) = -0.011 to 0.104) and evidence for a genetic difference between R. hageni transects (FST = 0.070, 95% CI = 0.025 to 0.108). This suggests a lack of budding and that mating flight dispersal is not limited over the study distance. These results indicate that within the study area R. flavipes and R. hageni have very similar breeding systems characterized by monogamous pairs of reproductives headed by slightly inbred reproductives and that few of these live long enough to produce more than a few neotenics. Results using mtDNA sequence data show two clades for each of the two species, R. flavipes and R. hageni. When comparing clades using microsatellite data, no significant difference between the clades was found for R. hageni, but a significant difference was found between clades for R. flavipes.

In 2004 through 2007, biological and ecological studies were conducted on the stink bug complex across Eastern North Carolina with emphasis on the brown stink bug, Euschistus servus (Hemiptera: Pentatomidae). Ecological studies included the use of survey samples, pheromone traps, and black light traps to monitor brown stink and green stink bug, Acrosternum hilare (Hemiptera: Pentatomidae), movement across selected Eastern North Carolina agro-ecosystems. Ecological research also focused on the movement of brown stink bugs within a wheat / corn agro-ecosystem through the use of sweep net samples and whole plant examinations, along with the vertical distribution of brown stink bugs on corn plants. Based upon brown stink bugs ability to fully complete the F1 generation within wheat in NC, historical weather data was examined utilizing a sine wave growing degree day model to predict the number of generations possible. The relationship among differing stink bug boll-feeding symptoms (external signs vs. internal symptoms) and boll damage to lint gin-out and quality were also examined. The last ecological study focused on the evaluation of the relationship between stink bug pressure and yield under a regressive spray treatment. A molecular study was conducted to help validate brown stink bug movement between crops by separating proteins of crop host from insect guts utilizing gel electrophoresis and mass finger printing the peptides. The peptides were then searched against the Viridiplantea data base for conformation which crop host proteins were derived from. Results from this work have given some insight to the biological and ecological movement of stink bugs across Eastern North Carolina. It has also demonstrated that there is a need for further investigation into the stink bug complex.

Atmospheric pressure plasma discharge (APPD) has been intensely studied in the past fifteen years as a method of sterilization. The effects of APPD on insects were previously unknown. The purpose of this study was to examine whether plasma could be useful for insect and mite control, determine the mode of action on arthropods, and optimize the discharge in order to achieve the shortest APPD treatment times. A positive correlation was found between exposure time to APPD and insect mortality with the level of mortality also increasing with time after treatment for western flower thrips, Frankliniella occidentalis (Pergande), tobacco thrips, Frankliniella fusca (Hinds), Asian tiger mosquito, Aedes albopictus (Skuse), two-spotted spider mite, Tetranychus urticae Koch, and German cockroach, Blattella germanica (L.). Generally, mortality was negatively correlated with the weight of the insect. Cockroaches exposed to APPD for 60, 90, 120 and 180s lost on average 7.5 ± 0.8, 8.1 ± 0.6, 8.7 ± 0.4, and 10.1 ± 1.1 (±1 SEM) mg of water weight, respectively, which was an increase over that of the controls. The metabolic rate of cockroaches exposed to plasma for 180 s increased from 0.80 ± 0.03 to 1.07 ± 0.04 ml of oxygen consumed mg-cockroach -1 h-1 at STP. The level of cuticular hydrocarbons identified by EI GC-MS were not significantly affected by plasma exposure in the green peach aphid, Myzus persicae (Sulzer), German cockroach, and citrus mealybug Planococcus citri (Risso) except for a reduction in n-tritriacontane only in the latter. However, changes in the behavior of cockroaches after plasma exposure including the loss of photo-, vibro-, and thigmotropic responses, inability to right themselves, and hyperexcitatory symptoms, suggests that the site-of-action of APPD in insects is the nervous and/or neuromuscular system. The LT50 of German cockroaches, western flower thrips, and citrus mealybugs 24 h after exposure to a 37°C helium discharge was 333.77, 28.72, and 999.95 s, respectively. The LT50?s 24 h after exposure to a 37°C, 0.5% oxygen/99.5% helium discharge was 232.67, 19.99, <13.83 s, respectively. The LT50 of German cockroaches, western flower thrips, and citrus mealybugs 24 h after exposure to the 50 ± 2°C, helium discharge was 117.80, 13.83, and 26.62 s, respectively. No mortality resulted in German cockroaches or citrus mealybugs after exposure to a helium atmosphere followed by 50°C air, however the LT50 of western flower thrips was 29.04 s, based on the mortality recorded 24 h after treatment. The addition of oxygen or heat to the discharge resulted in higher mortality in cockroaches and mealybugs but not thrips.

Oriental fruit moth, Grapholita molesta (Busck), has been a primary pest of peaches for many years throughout the world, and recently it has also emerged as a key pest of apples in the eastern United States. The implementation of the Food Quality Protection Act has eliminated the use of many organophosphate insecticides and encouraged the search for alternatives to organophosphates for control of Oriental fruit moth. Large and small plot studies were conducted to evaluate mating disruption as an alternative control tactic against Oriental fruit moth in North Carolina apple orchards during 2000-2002. The efficacy of Isomate-M 100 pheromone dispensers and microencapsulated sprayable pheromone was compared to insecticide-treated and non-managed orchards. Pheromone trap catches were significantly reduced in mating disruption blocks compared with conventional and non-managed orchards. Pheromone traps placed in the upper canopy captured significantly more moths than traps placed in the lower canopy across all treatments. Male OFM responded optimally to traps baited with 100 µg lures compared with 30 and 300 µg lures regardless of treatment. The loss of OFM pheromone from red rubber septa over a four-wk period exhibited a first-order release rate for septa loaded with 100 and 300 µg pheromone, but a more constant release rate from septa loaded with 30 µg pheromone. Based on pheromone trap captures, there was little difference among rates of sprayable pheromone ranging from 12.4 to 49.1 g (ai)/ha, but efficacy declined at 2.4 g (ai)/ha applied at monthly intervals. The 6.2 g (ai)/ha rate applied at 2-wk intervals was significantly less effective than monthly applications of 12.4 and 24.7 g (ai)/ha. Significantly fewer moths were caught in pheromone traps deployed in blocks treated in late May with Isomate-M 100, Isomate-M Rosso and Isomate-M 100 plus 3M sprayable pheromone compared with traps in conventional insecticide treatments, and Isomate-M 100 applied in late June. Overall, fruit damage by OFM larvae was quite low in mating disruption blocks.

Ledrinae represent a relatively small subfamily within the very large and diverse leafhopper family Cicadellidae. Prior to this study, the subfamily contained approximately 450 species in 5 tribes and 73 genera distributed worldwide, but primarily in Australia, Africa, and the Indomalayan region. Several authors have suggested Ledrinae are not monophyletic, and recent studies based on molecular and morphological data have called the existing classification into question. The goals of this study were to collect and analyze morphological data under rigorous phylogenetic criteria in order to test the monophyly of Ledrinae, provide robust definitions for the subfamily and its tribes, and provide a phylogenetic framework for understanding relationships among these leafhoppers. New phylogenetic hypotheses are presented here regarding the monophyly of Ledrinae and its included tribes. A total of 235 morphological characters were coded for 60 species from 31 genera in the tribes Ledrini and Petalocephalini, 5 species from the tribes Stenocotini, Thymbrini, and Xerophloeini, and 10 species selected as outgroups from various other cicadellid subfamilies. Data were analyzed in PAUP* and resulted in a single completely resolved topology with many well-supported nodes. Ledrinae, as previously defined, was found to be polyphyletic with respect to Stenocotini, Thymbrini, and various ledrine genera, which were placed with the outgroup taxa. Stenocotini and Thymbrini were placed with Tartessinae, agreeing with results of other recent studies. Rubria, Hespenedra, and the Afrorubria genus group formed independent lineages within Ledrinae. Xerophloeini was placed as a basal lineage within Ledrinae closely associated with the Afrorubria group. Ledrini and Petalocephalini, as previously defined, did not form monophyletic lineages, but were randomly interspersed with respect to one another. Stenocotini and Thymbrini are here removed to the subfamily Tartessinae, and Petalocephalini is made a synonym of Ledrini. Three new tribes are described within Ledrinae. Taxa placed outside of Ledrinae in this analysis are removed to other subfamilies or considered unplaced within Cicadellidae. This newly revised classification strengthens hypotheses that the Ledrinae are a very old group within Cicadellidae. As here defined, the subfamily includes five tribes with a total of 37 genera.