Workshop on research priorities for management and treatment of angiostrongyliasis(1).

In a concluding session of the workshop, the participants developed a list of 115 research and outreach needs, outlining the top 5-7 needs in each of 8 areas (Table). For complete information, including presenter details and abstracts, visit the workshop website at www.hawaii.edu/cowielab/Angio%20website%20home.htm.

Repellency of essential oils to Frankliniella occidentalis (Thysanoptera: Thripidae) as affected by type of oil and polymer release.

Eight essential oils [0.125-1.0% (vol:vol) in acetone] were separately deposited on leaf disks to evaluate their potential to repel western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), adult females. Two of the best-performing essential oils were incorporated into polymer matrices of methyl cellulose or alginate [0.5 or 1% (wt:vol)] to verify the potential of the polymer to extend repellency of oils over time (24-120 h). Results showed that at a concentration of 0.5%, Thymus vulgaris L. (common thyme) and Satureja montana L. (winter savory) were the most repellent essential oils. For these two treatments, no western flower thrips were counted on treated leaf disks 60 min after the start of the test. T. serpyllum and O. compactum also showed repellency values > or = 90% at this concentration. With both the alginate and methyl cellulose polymers, the incorporation of polymers into treatment solutions containing 0.5% concentrations of S. montana and T. serpyllum resulted in higher repellency compared with treatment solutions lacking these polymers for a minimum of 3 d. For the alginate polymer, differences associated with polymer concentrations were most dramatic. High repellency was maintained for 4 d when a 0.5% concentration of the alginate was used in combination with a 0.5% concentration of S. montana. The use of repellent oils with polymers that extend their repellency may prove useful for both pre- and postharvest applications in flower crops.

Preliminary study of genetic variation in Hawaiian isolates of Beauveria bassiana [Hypocreales, Cordycipitaceae].

There have been no previous surveys documenting genetic diversity in Beauveria bassiana (Balsamo) Vuillemin in Hawaii. We used PCR primers and DNA sequencing to genetically characterize 14 isolates of B. bassiana collected from insects in east Hawaii island (the largest Hawaiian island, known as the 'Big Island') and compared these with the 'GHA' strain found in the commercial product BotaniGard®. Twelve of the 14 Hawaiian isolates were unique and the GHA strain was not among those isolated from the wild. Our data provides evidence that genetic diversity of B. bassiana in Hawaii is high over small spatial scales.

Molecular markers discriminate closely related species Encarsia diaspidicola and Encarsia berlesei (Hymenoptera: Aphelinidae): biocontrol candidate agents for white peach scale in Hawaii.

We genetically characterized Encarsia diapsidicola Silvestri and Encarsia berlesei Howard (Hymenoptera: Aphelinidae) by two molecular methods: phylogenetic analysis of the cytochrome oxidase subunit I gene (COI) and intersimple sequence repeat-polymerase chain reaction (ISSR-PCR) DNA fingerprinting. These two closely related endoparasitoids are candidate biological control agents for the white peach scale, Pseudaulacaspis pentagona Targioni-Tozetti (Hemiptera: Diaspididae), in Hawaii. We developed species-specific COI molecular markers that discriminated the two species, and we tested the utility of the E. diaspidicola-specific COI marker to detect parasitism of white peach scale. The COI sequence data uncovered 46-bp differences between the two Encarsia spp. The level of COI genetic divergence between the two species was 9.7%, and the two clustered into their own clade on a parismonious phylogram. ISSR-PCR readily discriminated the two Encarsia spp. because each was observed with fixed species-specific banding patterns. The COI molecular markers were specific for each species because cross-reactivity was not observed with nontarget species. The E. diaspidicola-specific COI markers were successful at detecting parasitism of white peach scale by E. diaspidicola by 24 h. Both molecular marker types successfully discriminated the two Encarsia spp., whereas the COI markers will be useful as tools to assess levels of parasitism in the field and to study competitive interactions between parasitoids.

Use of shaking treatments and preharvest sprays of pyrethroid insecticides to reduce risk of yellowjackets and other insects on Christmas trees imported into Hawaii.

Insects are commonly found by Hawaii's quarantine inspectors on Christmas trees imported from the Pacific Northwest. To reduce the risk of importing yellowjacket (Vespula spp.) queens and other insects, an inspection and tree shaking certification program was begun in 1990. From 1993 to 2006, the annual percentage of shipped containers rated by Hawaii quarantine inspectors as moderately or highly infested with insects was significantly higher for manually shaken trees than for mechanically shaken trees. Between 1993 and 2001, 343 insect species in total were recovered from Christmas trees. Live western yellowjacket [Vespula pensylvanica (Saussure)] queens were intercepted both from containers certified as manually shaken and from containers certified as mechanically shaken. The standard manual shaking protocol removed about one-half of the queens from Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] trees that were naturally infested with western yellowjacket queens. We investigated the use of preharvest sprays of permethrin as a complement to shaking procedures used to control yellowjackets and other insects. Western yellowjacket queens and honey bees (surrogates for wasp pests) were exposed to Noble fir foliage that had been sprayed in the field with permethrin > 6 wk before harvest. Pesticide residues provided complete control (moribundity or mortality) in both species. The sprays did not affect needle retention or quality of Noble fir foliage. We conclude that preharvest sprays of pyrethroid insecticides could be used in combination with mechanical shaking to greatly reduce the quarantine risk of yellowjacket queens and other insects in exported Christmas trees.

Postharvest Population Reservoirs of Coffee Berry Borer (Coleoptera: Curculionidae) on Hawai'i Island.

Coffee berry borer, Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae), is the most damaging insect pest of coffee worldwide. Old coffee berries (raisins) are widely acknowledged as coffee berry borer reservoirs, yet few studies have attempted to quantify coffee berry borer populations in raisins remaining on farms postharvest. We collected ground and tree raisins at six coffee farms on Hawai'i Island to assess raisin density, infestation, coffee berry borer abundance, and adult mortality in three areas of each farm: trees, driplines (ground below the tree foliage), and center aisles (ground between tree rows). We also assessed infestation of the new season's crop by conducting whole-tree counts of infested green berries. Mean raisin density was significantly higher in the dripline compared to the center aisle and trees (131 vs 17 raisins per m2 and 12 raisins per tree, respectively). Raisin infestation was significantly higher in samples from trees (70%) relative to those from the dripline (22%) and center aisle (18%). Tree raisins had significantly higher coffee berry borer abundance compared to both areas of the ground (20 vs 3-5 coffee berry borer per raisin). Adult mortality was significantly higher on the ground (63-71%) compared to the trees (12%). We also observed a significant positive correlation between ground raisin density and infestation of the new season's crop. Across all farms, we estimated that 49.5% of the total coffee berry borer load was present in dripline raisins, 47.3% in tree raisins, and 3.2% in center aisle raisins. Our findings confirm the importance of whole-farm sanitation in coffee berry borer management by demonstrating the negative impact that poor postharvest control can have on the following season's crop.

Coffee berry borer (Hypothenemus hampei) (Coleoptera: Curculionidae) development across an elevational gradient on Hawai'i Island: Applying laboratory degree-day predictions to natural field populations.

Coffee berry borer (CBB, Hypothenemus hampei) (Coleoptera: Curculionidae: Scolytinae) is the most destructive pest of coffee worldwide. Information on CBB development times can be used to predict the initiation of new infestation cycles early in the coffee-growing season and thus inform the timing of insecticide applications. While laboratory estimates of CBB development under constant conditions exist, they have not been applied under the heterogeneous environmental conditions that characterize many coffee-growing regions. We measured CBB development times and abundance in commercial coffee farms across an elevational gradient on Hawai'i Island and applied thermal accumulation models from previous laboratory studies to test their fit to field data. Artificial lures were used to infest coffee berries at five farms ranging in elevation from 279-792 m, and weather variables were monitored at macro (farm-level) and micro (branch-level) scales. CBB development was followed in the field from the time of initial berry infestation by the founding female through the development of F1 mature adults. Mean development time from egg to adult across all sites was 38.5 ± 3.46 days, while the mean time required for the completion of a full life cycle (from time of infestation to presence of mature F1 females) was 50.9 ± 3.35 days. Development time increased with increasing elevation and decreasing temperature. Using macro-scale temperature data and two different estimates for the lower temperature threshold (14.9°C and 13.9°C), we estimated a mean requirement of 332 ± 14 degree-days and 386 ± 16 degree-days, respectively, from the time of berry infestation to the initiation of a new reproductive cycle in mature coffee berries. Similar estimates were obtained using micro-scale temperature data, indicating that macro-scale temperature monitoring is sufficient for life-cycle prediction. We also present a model relating elevation to number of CBB generations per month. Our findings suggest that CBB development times from laboratory studies are generally applicable to field conditions on Hawai'i Island and can be used as a decision support tool to improve IPM strategies for this worldwide pest of coffee.

Ionizing radiation for quarantine control of Opogona sacchari (Lepidoptera: Tineidae).

A discriminating irradiation dose of 150 gray (Gy) was used to determine the most tolerant immature stages of Opogona sacchari (Bojer) (Lepidoptera: Tineidae). Based on adult emergence, early and late pupae were determined to be the most tolerant stages, and they were significantly more tolerant than eggs, neonate larvae, and larvae that were 1, 2, or 3 wk old. Irradiation treatment of eggs, neonates, 1-wk-old larvae, 2-wk-old larvae, 3-wk-old larvae, early pupae, and late pupae at 150 Gy resulted in a 96, 96, 95, 73, 61, 8, and 9% reduction in adult emergence, respectively. Pupae were treated with irradiation doses between 60 and 400 Gy. Emergence to the adult stage was significantly reduced by irradiation, averaging 90% in experimental controls and 29% in the 400-Gy treatment. Egg production was also reduced by irradiation, although the average age of pupae at the time of irradiation had a larger effect on fecundity. In total, 2,527 pupae treated with 120 Gy eclosed and produced 47,221 eggs and three F1 larvae. In the 150-Gy treatment, 2,927 adults in total emerged from the 4,626 insects treated as pupae. These adults laid 62,878 eggs, none of which hatched. We conclude that a minimum dose of 150 Gy should be sufficient for sterilization of immature O. sacchari infesting export commodities.

Limonene, a citrus extract, for control of mealybugs and scale insects.

In a series of bioassays with mealybugs, aqueous solutions of 1% limonene were tested that used from 0.50 to 1.50% all purpose spray adjuvant (APSA)-80 as an emulsifier/surfactant. The two ingredients were added to water or to 0.1% Silwet L-77, an agricultural surfactant. Using 1% limonene, 0.75% APSA-80 and 0.1% Silwet L-77, a semitransparent mixture (primarily a microemulsion) was obtained that was safe for most plants and provided good control of mealybugs when sprayed or used in 1-min dips. Used at half strength, this mixture controlled > or =99% of whiteflies, whereas the full-strength mixture controlled from 69 to 100% of mealybugs and scales, including > or =93% control of root mealybugs. In side-by-side greenhouse tests, this mixture was superior to a 2% solution of insecticidal soap or a 2% solution of horticultural spray oil. Mortality of green scales on potted gardenia plants averaged 95, 89, and 88% on plants sprayed with limonene, insecticidal soap, or horticultural oil, respectively. In a related test, these same sprays killed 44.1, 22.7, or 12.5% of third and fourth instar clustering mealybugs, respectively. Limonene has promise as a safe, natural pesticide for insect pests on tolerant plants. Although 1% limonene solutions damaged certain species of ferns, gingers and delicate flowers, they caused no damage to ornamentals with thick, waxy leaves, such as palms, cycads, and orchids.

Potential of temperature, controlled atmospheres, and ozone fumigation to control thrips and mealybugs on ornamental plants for export.

Ozone (O3) fumigation is a potential quarantine treatment alternative for controlling stored-product pests and surface insect pests on fresh agricultural commodities. We explored the effects of temperature, treatment time, controlled atmospheres, and vacuum in combination with O3 to control two important pests of ornamental crops: western flower thrips, Frankliniella occidentalis (Pergande), and longtailed mealybug, Pseudococcus longispinus Targioni Tozzetti. Treatment parameters tested were O3 concentrations from 0 to 3,800 ppm, treatment durations were from 30 to 120 min, vacuums were from 0 to 0.41 bar below ambient, temperatures were from 32.2 to 40.6 degrees C, and controlled atmospheres were composed primarily of nitrogen, carbon dioxide, or breathing air [BA]. Treatment efficacy was enhanced by higher O3 concentration and temperature, lower oxygen, and longer treatment times. Reduced pressure was not an important factor. Mealybugs were more difficult to kill than thrips. A 30-min treatment of O3 at approximately 200 ppm in 100% CO2 at 37.8 degrees C killed 47.9 and 98.0% of mealybugs and adult female thrips, respectively. All of the ornamentals tested were damaged to some degree by O3 treatments. However, crops with thick leaves such as orchids exhibited little damage, and the waxy portions of certain flowers were not damaged. The results suggest that O3 has potential as a quarantine treatment to control thrips and mealybugs on selected commodities.

Control measures for slug and snail hosts of Angiostrongylus cantonensis, with special reference to the semi-slug Parmarion martensi.

Slugs and snails (class Gastropoda) are the obligate intermediate hosts of the rat lungworm, Angiostrongylus cantonensis. This nematode is the causative agent of human angiostrongyliasis and the most common cause of human eosinophilic meningoencephalitis. Humans can become infected by accidental consumption of slugs or snails and possibly flatworms (or a portion of one of these animals) in fresh produce, but the slime from these animals can contain nematodes and may also constitute a disease risk. Gastropod carriers in Hawa'i include, among other species, giant African snails, veronicellid slugs, and the semi-slug Parmarion martensi. This latter species was first discovered on the island of Hawa'i in 2004 and is now common in the area where the majority of the state's documented cases of human angiostrongyliasis occurred between 2005 and 2011. This species is considered a high risk carrier of A. cantonensis because of its climbing behavior, abundance around human dwellings, and high worm burdens. One individual collected from east Hawa'i Island contained >6,800 infective third stage A. cantonensis larvae. Common and efficient control methods for slugs and snails include sanitation (eg, removal of objects that serve as hiding places) and the use of poison food baits, such as those containing metaldehyde and iron. An iron-containing bait that is relatively safe to non-target organisms was effective in controlling semi-slugs in cage experiments, although it killed more slowly than a metaldehyde-containing bait and the majority of slugs affected did not die until 1-2 weeks following ingestion.

Sex attractant for the banana moth, Opogona sacchari Bojer (Lepidoptera: Tineidae): provisional identification and field evaluation.

BACKGROUND: The banana moth, Opogona sacchari Bojer, is a polyphagous agricultural pest in many tropical areas of the world. The identification of an attractant for male O. sacchari could offer new methods for detection, study and control. RESULTS: A compound extracted from female O. sacchari elicited responses from antennae of male moths. This compound was identified as a 2/3,(Z)13-octadecadienal by gas chromatography-mass spectrometry. An analog, 2/3,(Z)13-octadecadienol, was also detected in some extracts at roughly a 1:20 ratio (alcohol:aldehyde) but did not elicit responses from antennae of male moths. Electroantennograms of synthetic candidate dienals found the strongest responses from (Z, Z)-2,13-octadecadienal and (E, Z)-2,13-octadecadienal. In field trials, (E, Z)-2,13-octadecadienal attracted more male O. sacchari than (Z, Z)-2,13-octadecadienal. Attraction was not improved for either of these compounds when the corresponding stereoisomeric alcohol was added at ratios of 1:1, 1:10 or 1:100 (alcohol:aldehyde). Jackson sticky traps containing 250 microg lures of (E, Z)-2,13-octadecadienal caught as many males as did traps holding virgin females. CONCLUSION: (E, Z)-2,13-octadecadienal has been identified as an attractant for O. sacchari males and can be used as a monitoring lure of populations of this moth.