Hemipteran pests feed directly on cotton fruiting structures (bolls) causing damage to fiber and yield. Herbivore-induced volatile emissions have been well studied with regard to leaf-chewing insects, but no research has examined the release of volatiles from developing cotton bolls in response to damage from piercing-sucking insects. We compared volatile emissions from bolls in response to feeding damage by brown stink bug, Euschistus servus (Say), southern green stink bug, Nezara viridula, (L.), and the leaf footed bug, Leptoglossus phyllopus (L.) under laboratory conditions. Volatile emissions from bolls in response to N. viridula and mechanical damage were investigated under field conditions. Volatiles were collected using dynamic head-space sampling and analyzed by gas chromatography/mass spectrometry. Under laboratory conditions, feeding by hemipterans resulted in a significant increase in volatile emissions from bolls compared with undamaged bolls. Damaged bolls released significantly greater amounts of acyclic terpenes and methyl ketones compared with undamaged bolls. Feeding by different hemipteran species elicited a similar quantitative increase in emissions, but significant differences were detected in the emissions of some individual compounds. Under field conditions, feeding damage by N. viridula resulted in significantly greater volatile emissions compared with undamaged and mechanically-damaged bolls indicating that physical damage alone did not account for the complete blend of volatiles released in response to biotic injury. During feeding, hemipterans inject a complex blend of salivary and digestive enzymes, and some of these compounds may activate volatile induction from bolls. The implication for piercing-sucking damage on biochemical pathways mediating volatile synthesis is discussed.

The onion thrips, Thrips tabaci (Lindeman), is the only known vector of Iris yellow spot virus (IYSV). IYSV was detected in Georgia for the first time in 2003. Phylogenetic analysis using nucleotide sequences of the IYSV capsid gene indicated that it may have been accidentally introduced from repackaging of imported Peruvian onions in the Vidalia onion-growing region. The tobacco thrips, Frankliniella fusca (Hinds), has been the dominant thrips species on onions in Georgia. However, in recent years the incidence of T. tabaci on onions has been consistently increasing. Laboratory competition studies indicated that T. tabaci outcompeted F. fusca on onion foliage. This led to speculation that a new biotype of T. tabaci may have been introduced along with IYSV through importation of Peruvian onions. This hypothesis was tested by analyzing variations in the mitochondrial cytochrome oxidase I gene and internal transcribed spacer region 2 of T. tabaci populations from Georgia and Peru. DNA was extracted from T. tabaci samples from Georgia and Peru and subjected to PCR using specific primers. The resulting amplicons were sequenced. Parsimony and Bayesian analysis of the COI sequences indicated that all the Peruvian taxa fell into a single clade along with one Georgia taxon. All the other Georgia taxa were in a separate clade. ITS2 sequence comparisons indicated that Georgia and Peru taxa were found in numerous clades. High variation among taxa from each region indicated that ITS2 may not be suitable to assess intraspecific variation among T. tabaci populations.

Coupled gas chromatography and electroantennogram detection (GC-EAD) analyses of headspace volatiles from apple host tissues revealed a total of 16 compounds to which female dogwood borer, Synanthedon scitula (Harris), antennae responded. There were no differences in the amplitude of the response of antennae from virgin and mated females, and no consistent responses to host odors were generated from male antennae. Four compounds, including octanal, nonanal, decanal, and methyl salicylate, were identified from all headspace collections taken from apple trees. Use of the solid-phase microextraction (SPME) technique revealed that a single volatile compound, α-bergamotene, emanating from larval dogwood borer frass elicited a strong female antennal response. This compound was also present in headspace collections from ‘Red Chief Delicious’ apple trees with burr knot tissue infested with dogwood borer larvae and from 1-d-old cut bark on ‘Granny Smith’ trees, suggesting that it is produced by apple trees in response to injury. An additional compound, methyl-2,4-decadienoate, present only in headspace collections from burr knots infested with dogwood borer larvae on ‘Granny Smith’ trees elicited a strong female antennal response.

A study was conducted to determine the utility of ground cover vegetation in managing the natural enemies of spruce spider mite (Oligonychus ununguis Jacobi) in Fraser fir production areas in 2 locations in North Carolina (Laurel Springs, Waynesville). Predatory phytoseiid mites were sampled by collecting vegetation from 4 ground cover species in experimental Fraser fir plots: white Dutch clover (Trifolium repens L.), mammoth red clover (Trifolium pretense L.), birdfoot trefoil (Lotus corniculatus L.), and fescue (Festuca spp.). The most abundant phytoseiid mite species were Typhlodromips sessor(DeLeon), Arrenoseius morgani(Chant), Proprioseiopsis solens (DeLeon), and Typhlodromalus peregrinus (Muma). There were no statistical differences in the effects of ground cover vegetation on phytoseiid mite abundance or diversity.

Studies were conducted to compare the effect of trap placement above and below sex pheromone mating disruption (MD) dispensers on captures of codling moth, Cydia pomonella (L.), and oriental fruit moth, Grapholita molesta (Busck), in apple orchards. Traps were placed at a height of 1.8 m or 4.5 m in the tree canopy whereas MD dispensers were placed at 3.1 m within the tree canopy; an adjacent set of plots were treated similarly with only insecticides (nonMD). All trees were approximately 4.8 - 5.1 m in height. Capture of codling moth adults in traps was highest in traps placed at 4.5 m in both MD and nonMD plots and lowest in traps placed at 1.8 m in MD treated plots. Reduction in adult codling moth capture was low to moderate (< 64%) in traps placed above dispensers and higher (>70%) in traps placed below dispensers over both years. Oriental fruit moth adult capture in 2007 was lowest in traps placed at 1.8 m in plots treated with MD. In 2008, capture of oriental fruit moth was highest in traps placed at 4.5 m.

Our study reports the results of field and garden experiments designed to quantitatively evaluate the impact of herbivory by a weed biological control agent, the stem-mining weevil Mecinus janthinus Germar, on the growth of its exotic host Dalmatian toadflax, Linaria dalmatica (L.) Miller. Herbivory by M. janthinus under both natural and manipulated environmental conditions inhibited L. dalmatica growth. Reductions in stem length, biomass, and growth were more pronounced for plants subjected to both exophagous (adult) and endophagous (larval) feeding injury than for plants exposed only to adult folivory. Decreases we observed in root biomass could additionally inhibit shoot production from lateral roots. This provides a plausible mechanism explaining anecdotal reports correlating the reduced spread of L. dalmatica with attack by M. janthinus. Our results indicate that L. dalmatica growth is compromised once a threshold density equivalent to 5 M. janthinus larvae per stem is exceeded. The consistency of growth responses observed in this study suggests that a mechanistic/quantitative approach, such as measuring the impact of M. janthinus herbivory on L. dalmatica, is a robust and relevant method for postrelease evaluations of weed biocontrol efficacy.

Field surveys were conducted in 2007 - 2009 to determine the diversity of mosquito species occurring in Shandong Province, China. As a result, 31 species of mosquitoes were identified. Culex pipiens pallens Coquillett was the most common species collected. Aedes albopictus Skuse, Anopheles sinensis Wiedemann, and Cx. tritaeniorhynchus Giles also were commonly collected. These 4 species have been documented as the vectors of malaria, dengue, and epidemic encephalitis in China. At least 10 species identified are disease vectors in Shandong Province, and other species could be considered potential vectors of other diseases. Mosquito larvae were routinely collected from natural and artificial structures containing water. The diversity of these water-filled containers might explain the cooccurrence of various culicid species in some localities surveyed. The ecology and breeding behavior of these mosquito species should be further studied to optimize surveillance and management programs and to prevent the emergence of mosquito-transmitted diseases in human and other animal populations in the area.

The entomopathogenic fungus Isaria fumosorosea Wize (PFR97^® strain, Certis USA, Columbia, MD) was tested as a mortality agent of the cycad aulacaspis scale, Aulacaspis yasumatsui Takagi, at 2 temperatures in the laboratory. First instars of A. yasumatsui were treated with 1 of 4 concentrations of I. fumosorosea (5.4 × 10⁷, 9.9 × 10⁶, 6.4 × 10⁵, or 1.8 × 10⁵ blastospores/ml of water) or a water only control. Following treatment, insects were held at either 20 or 30°C. The highest concentration treatment resulted in the highest mean infection rate at 8 d postapplication (73 ± 4.2% at 30°C; 84 ± 3.7% at 20°C). However, there was no interaction between blastospore concentration and temperature for infection rate. The lowest mortality rate was obtained with the highest concentration of blastospores under 20°C (13 ± 3%). The LC₅₀ at 20° and 30°C were 6.1 × 10⁶ and 5.3 × 10⁶ blastospores/ml, respectively. The LT₅₀ was lower at 30°C than at 20°C for the 3 highest concentrations. The radial growth of the fungus on potato dextrose agar 20 d after inoculation was 37% greater at 30°C than its radial growth at 20°C. These results indicate that I. fumosorosea may be a new biological control weapon for suppressing infestations of cycads by A. yasumatsui. This is the first report of I. fumosorosea being evaluated to infect an armored scale insect.