Influence of Odor-bait, CultivarType, and 

 Adjacent Habitat Composition on 

 Performance of Perimeter Traps for 

 Controlling Apple Maggot Flies 



Sara Hoffmann, Robin Mittenthal, Brad Chandler, Gerald Lafleur, Starker Wright, 

 Paul Appleton, Max Becker, Sara Dynok, and Ron Prokopy 

 Department of Entomology, University of Massachusetts 



Apple maggot flies (AMF) that immigrate into 

 commercial apple orchard blocks from surrounding 

 areas containing unmanaged host trees are the flies 

 responsible for the great majority of infestation of fruit 

 in commercial orchards. Previously, we have found 

 that using perimeter-row, odor-baited red spheres to 

 intercept immigrating AMF is an effective control 

 method. More specifically, our findings have suggested 

 that surrounding an apple orchard block with spheres 

 baited with butyl hexanoate (BH) and placed 5 m apart 

 will effectively prevent AMF from penetrating into the 

 block. 



Here, we present the results of experiments 

 conducted in 2000 and 2001 designed to determine 

 whether (1) spacing spheres 10 m apart on perimeter- 

 row apple trees is as effective as spacing spheres 5 m 

 apart in preventing AMF penetration into orchard 

 blocks, (2) perimeter-row spheres baited with a five- 

 compound blend of fruit odor volatiles are more 

 effective than traditional BH-baited spheres in 

 preventing AMF penetration into interiors of blocks, 

 (3) the presence of AMF-susceptible compared with 

 AMF-tolerant cultivars comprising front-row apple 

 trees affects front-row-trap captures and AMF 

 penetration into interiors of blocks, and (4) adjacent 

 habitat affects AMF population numbers immigrating 

 into commercial orchards. 



Materials & Methods 



In 2001, 10 Massachusetts commercial orchard 

 blocks were involved in our experiment (initially, we 

 used 12 commercial orchard blocks in 2001, but for 



the purpose of this article, we excluded two of them 

 due to unusually high AMF populations that would blur 

 data trends in the remaining 10 blocks). Five blocks 

 had front-row cultivars that were comparatively 

 susceptible to AMF (Gala, Jonagold, or Fuji) and five 

 blocks had comparatively tolerant front-row cultivars 

 (Mcintosh or Empire). Each orchard block had an 

 adjacent habitat of woods, hedgerow, or open field. 

 Each block in the 1 commercial orchards was divided 

 into three plots (Figure 1). Plots A and B had a 45m 

 length of front row and a depth of seven rows. The 

 front row in plots A and B contained five sticky red 

 spheres, spaced 10m apart. Each was baited with either 

 the five-compound blend (BH, hexyl butanoate, butyl 

 butanoate, pentyl hexanoate, and propyl hexanoate) or 

 BH alone. Plots A and B received no insecticide spray 

 to control AMF. Plot C (termed grower sprayed) had a 

 30m length of front row and a depth of seven rows. It 

 was sprayed by the grower two or three times with an 

 organophosphate insecticide to control AMF. Each 

 of the two sides of plots A and B, as well as the back 

 row (row 7), contained red spheres spaced 5 m apart, 

 baited with butyl hexanoate. Plot C had no perimeter, 

 side, or back-row spheres. Rows 3 and 4 contained six 

 unbaited sticky red spheres (four in the grower-sprayed 

 plot due to the smaller size) to monitor AMF 

 penetration into the interior of plots. Traps were 

 deployed in late June and remained through the 

 beginning of October. Every 2 weeks, traps were 

 cleaned and captured AMF were counted. 



The protocol for our 2001 experiment was based 

 on results of a test conducted in 2000, in which we 

 evaluated AMF penetration into orchard blocks by 



20 



Fruit Notes, Volume 67, Spring, 2002 



