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Temperature-related studies were conducted on Drosophila suzukii Matsumura (Diptera: Drosophilidae: Drosophilini). From 10-28°C, temperature had a significant impact on blueberries, Vaccinium corymbosum L. (Ericales: Ericaceae), and cherries, Prunus avium (L.) L. 1755 (Rosales: Rosaceae), important commercial hosts of D. suzukii. Temperature had a significant influence on D. suzukii developmental period, survival, and fecundity, with decreasing developmental periods as temperatures increased to 28°C. At 30°C, the highest temperature tested, development periods increased, indicating that above this temperature the developmental extremes for the species were approached. D. suzukii reared on blueberries had lower fecundity than reared on cherries at all temperatures where reproduction occurred. The highest net reproductive rate (Ro) and intrinsic rate of population increase (rm) were recorded on cherries at 22°C and was 195.1 and 0.22, respectively. Estimations using linear and nonlinear fit for the minimum, optimal, and maximum temperatures where development can take place were respectively, 7.2, 28.1, and 42.1°C. The rm values were minimal, optimal, and maximal at 13.4, 21.0, and 29.3°C, respectively. Our laboratory cultures of D. suzukii displayed high rates of infection for Wolbachia spp. (Rickettsiales: Rickettsiaceae), and this infection may have impacted fecundity found in this study. A temperature-dependent matrix population estimation model using fecundity and survival data were run to determine whether these data could predict D. suzukii pressure based on environmental conditions. The model was applied to compare the 2011 and 2012 crop seasons in an important cherry production region. Population estimates using the model explained different risk levels during the key cherry harvest period between these seasons. [ABSTRACT FROM AUTHOR]

The influence of media type and moisture on adult development and pupal mortality in western cherry fruit fly, Rhagoletis indifferens Curran (Diptera:Tephritidae), was assessed using the pupal-adult and the larval-pupal stage. Inside containers, a higher percent of flies that emerged from dry loam was deformed (44.2%, 1-era-depth loam; 84.4%, 5-era-depth loam) than flies from 16% moist loam and dry and 16% moist lab soil (peat moss-sand mix) (0-14.9%). Percent of flies deformed from dry sand (22.1%, 1-cm depth; 49.5%, 5-era depth) was greater than from 16% moist sand and dry and 16% moist peat moss (0-10.5%). Percents of flies deformed from 8% moist loam, lab soil, sand, and peat moss (0-5.8%) did not differ. Pupae suffered higher mortality at 7 and 14 d after larvae were dropped onto dry loam and dry sand (68.2-94.0%) than dry lab soil and dry peat moss (3.0-53.0%); respective mortalities at 21 and 28 d were similar (81.3-96.0 versus 64.7-97.9%). Pupal mortality in moist media was lower (0.5- 40.3%) than in dry media. In outdoor tests, pupal mortality was also higher in dry loam than other dry media. In nature, 60.9% of pupae in dry sandy loams in late summer were dead. Results suggest R. indifferens has not yet evolved to fully cope with dry soils and that pupation in media with traits similar to those of peat moss or a peat moss-sand mix could reduce negative effects of dry environments on fly survival. [ABSTRACT FROM AUTHOR]

We studied the timing of reproductive maturity of cherry fruit fly, Rhagoletis cingulata (Loew), a key pest of sweet and tart cherries in the eastern United States. To determine when cherry fruit fly females become reproductively mature in managed and natural habitats, we deployed traps in sweet and tart cherry orchards and nearby stands of the ancestral host tree, black cherry. Flies were removed from the traps arid females were dissected to determine the presence of fully developed eggs. We found that capture of reproductively mature female flies occurred earlier in orchards that are not sprayed with insecticides than in sprayed orchards or in black cherry tree sites. In addition, the gap between the flights of immature and mature females in unmanaged sweet or tart cherry orchards was shorter than in managed orchards or black cherry tree sites. We also determined fruit color, size, and skin hardness to characterize the progression of fruit maturity. We found that fruit became mature earlier in sweet and tart cherry orchards than in black cherry tree sites. This study indicates that the timing of female reproductive maturity is plastic and varies among cherry fruit fly populations present in distinct habitats. Variation in the timing of reproductive maturity is related to the fruit maturity period of distinct host plant species and to orchard management. [ABSTRACT FROM AUTHOR]

Field trapping studies were conducted to determine whether feral blueberry maggot flies, Rhagoletis mendax Curran, and Eastern cherry fruit flies, R. cingulata (Loew), respond to natal host-fruit volatiles. Subsequent experiments were conducted to evaluate the potential of using simple and inexpensive fruit juice concentrate lures to monitor these key pests of blueberries and cherries, respectively. The presence of ripe blueberries and ripe tart cherries in enclosures that permitted escape of fruit volatiles significantly increased captures of R. mendax and R. cingulata, respectively, on adjacent sticky traps compared with traps without adjacent fruit. R. mendax were not affected by addition of blueberry concentrate to Pherocon AM traps with or without ammonium acetate. Pherocon AM boards prebaited with ammonium acetate directly incorporated into the sticky Tangle-Foot coating were equally effective as unbaited Pherocon AM boards deployed with separate ammonium acetate dispensers for monitoring It. mendax. A cherry juice concentrate increased captures of R. cingulata on unbaited Pherocon AM but not Rebell traps. In addition, combining cherry juice concentrate and ammonium acetate on Pherocon AM traps increased captures of R. cingulata compared with captures on traps with either stimulus alone. Adding ammonium acetate lures to Rebell traps more than doubled captures of R. cingulata over that on unbaited Rebell traps. Our results show that feral R. mendax and R. cingulata flies are attracted to the volatiles emitted from their host fruit and that this may be exploited to improve monitoring of these important fruit pests. [ABSTRACT FROM AUTHOR]

The eastern cherry fruit fly, Rhagoletis cingulata (Loew), and black cherry fruit fly, R. fausta (Osten Sacken), are the most important insect pests of cherries Prunus spp. in the eastern and midwestern United States. In 1998, we studied the responses of cherry fruit fly species using the recommended V-shaped Pherocon AM board. Significantly more R. cingulata flies were caught on boards with aqueous solutions of ammonium baits compared with boards that had solid ammonium baits mixed into the Tangle-Trap. Captures of R. fausta flies were low in 1998 and the weekly trapping data never exceeded a total of five adults. In 1999, several commercial traps were evaluated including the unbaited, three-dimensional Rebell trap and different types of ammonium baited spheres and boards including a 9-cm-diameter red sphere, a modified version of the Ladd trap (L & S trap), and the Pherocon AM yellow board in the vertical and V-shaped orientations. There were significantly more R. fausta flies caught on unbaited Rebell traps compared with any other commercial traps studied. Red sphere treatments (regardless of baiting system) consistently captured significantly fewer R. fausta flies than any other treatment evaluated. For R. cingulata, total captures on unbaited Rebell traps were not significantly different from other commercial traps including the 9-cm-diameter red spheres baited with ammonium acetate mixed into the Tangle-Trap, L & S traps, and the baited Pherocon AM yellow boards deployed in a vertical orientation. The study demonstrated that the unbaited Rebell trap was the most effective and selective device evaluated for monitoring R. fausta and R. cingulata flies. In addition, red sphere (9-cm-diameter) traps were found ineffective for use in R. fausta monitoring programs. [ABSTRACT FROM PUBLISHER]