Attraction of the Invasive Halyomorpha halys (Hemiptera: Pentatomidae) to Traps Baited with Semiochemical Stimuli Across the United States.

A recent identification of the two-component aggregation pheromone of the invasive stink bug species, Halyomorpha halys (Stål), in association with a synergist, has greatly improved the ability to accurately monitor the seasonal abundance and distribution of this destructive pest. We evaluated the attraction of H. halys to black pyramid traps baited with lures containing the pheromone alone, the synergist methyl (2E,4E,6Z)-decatrienoate (MDT) alone, and the two lures in combination. Traps were deployed around areas of agricultural production including fruit orchards, vegetables, ornamentals, or row crops in Delaware, Maryland, North Carolina, New Jersey, New York, Ohio, Oregon, Pennsylvania, Virginia, and West Virginia from mid-April to mid-October, 2012 and 2013. We confirmed that H. halys adults and nymphs are attracted to the aggregation pheromone season long, but that attraction is significantly increased with the addition of the synergist MDT. H. halys adults were detected in April with peak captures of overwintering adults in mid- to late May. The largest adult captures were late in the summer, typically in early September. Nymphal captures began in late May and continued season long. Total captures declined rapidly in autumn and ceased by mid-October. Captures were greatest at locations in the Eastern Inland region, followed by those in the Eastern Coastal Plain and Pacific Northwest. Importantly, regardless of location in the United States, all mobile life stages of H. halys consistently responded to the combination of H. halys aggregation pheromone and the synergist throughout the entire season, suggesting that these stimuli will be useful tools to monitor for H. halys in managed systems.

Seasonal abundance, life history, and parasitism of Caloptilia porphyretica (Lepidoptera: Gracillariidae), a leafminer of highbush blueberry.

The leafminer Caloptilia porphyretica Braun (Lepidoptera: Gracillariidae), has become a frequent pest in commercial highbush blueberries, Vaccinium corymbosum L., in New Jersey, but little is known about its seasonal abundance, life history, and parasitism rates. Monitoring programs were conducted from 2003 to 2006 on seven blueberry farms to determine the relative abundance of this leafminer by using pheromone-baited traps and by sampling vegetative and flower/fruit clusters and new shoot growth. We found at least three distinct generations per year, with populations reaching their highest peak in the second generation. Laboratory studies characterized the life history of C. porphyretica and its parasitoid Pholetesor sp. prob. salalicus (Mason). The developmental period of C. porphyretica, from egg to adult, took 927, 838, and 912 degree-days (DD) at 20, 25, and 30 degrees C, respectively, by using a developmental threshold of 4.8 degrees C. This was equivalent to an average of 892 DD to complete development to adult, which compared with 870 and 880 DD between the first and second, and second and third generations, respectively, by using pheromone trap data averaged from 2004 to 2006. Although C. porphyretica populations varied greatly, the number of larvae in cluster and new shoot samples was highly correlated with the number of adults in traps. Field parasitism rate was -29%, with the braconid Pholetesor sp. the most abundant parasitoid. Ten of the 13 parasitoid species collected belonged to the family Eulophidae. When different ages of leafminers were exposed to Pholetesor sp., we found that the parasitoid attacks 9-15-d-old instars that reside in the mines of leaves.

Optimization of pheromone deployment for effective mating disruption of oriental beetle (Coleoptera: Scarabaeidae) in commercial blueberries.

Cost is a potential limiting factor in the adoption of mating disruption to control oriental beetle, Anomala orientalis (Waterhouse) (Coleoptera: Scarabaeidae). A 3-yr study was conducted in 1-ha blueberry, Vaccinium corymbosum L., plots to test the possibility of lowering cost by reducing the number of point-source dispensers and pheromone [(Z)-7-tetradecen-2-one] concentrations, while maintaining mating disruption. Trap shutdown, as measured by the disruption index (DI), caged females, and sentinel potted-plants with tethered females were used to assess the success of mating disruption. Disrupted plots had DI values of > or = 93% in all years, and a lower percentage of mated females, compared with control plots. However, DI values were > or = 95% at > or = 50 dispensers per ha. When 25 dispensers containing 0.05 g of active ingredient (AI) were used per hectare, the numbers of males in female cages and larvae in sentinel pots were similar to controls. Thus, dispenser density was critical for successful mating disruption of oriental beetles. Male oriental beetles approach the dispensers at all times of the day according to field observations, indicative of competitive attraction as a potential mechanism for mating disruption. However, at peak activity, greater male attraction was observed to dispensers containing 0.1 g of pheromone than 0.05 or 0.025 g, demonstrating the importance of pheromone rate. Although dispensers continued to emit pheromone for at least 7 wk in the field, emission rates dropped to levels close to 0 after 3 wk. We conclude that deployment of > or = 50 dispensers/ha at > or = 0.1 g (AI) per dispenser is the most effective rate for mating disruption of oriental beetle in blueberries.

Estimating Yield and Economic Loss from Constriction Canker of Peach.

Constriction cankers, caused by Phomopsis amygdali, girdle and kill fruiting twigs which results in a direct crop loss. To quantitatively determine this loss from 1996 to 1998, the number of fruit lost per infected shoot was estimated as a function of disease incidence in 21 severely infected orchards in New Jersey. For each cultivar in 1997 and 1998, the distribution of fruit sizes at harvest and prices at shipping were used to calculate total crop value for typical expected yields. Economic loss was then calculated from yield loss and crop value estimates. The overall percent yield loss mean across all sites and cultivars, unadjusted for fruit remaining on infected shoots, was 22.2, 30.7, and 23.7% for 1996, 1997, and 1998, respectively. The frequency of these losses were not normally distributed, and the nonparametric Friedman test indicated that yield loss was significantly different among years. Assuming the remaining fruit on infected shoots were harvested, yield losses for 1997 and 1998 were 28.5 and 21.0%, which translated into average economic losses of $4,009 and 2,803/ha, respectively, for an expected yield level of 14,010 kg/ha. These loss values justify control measures for management of constriction canker in severely infected orchards.