Figure 3: R esponse of unmarked wild flies 



25 - 



20 



0) -D 



I t 



a> o 

 a 



1 5 



BH= B u tyl hex anoate, AC= Ammonium 



carbonate, Food = Presence or absence of 



natural sources of food on trees 



absence of food on the apple trees (Figure 1). 

 Response of immature flies to lures and traps 

 was much lower than that of mature flies. 

 Although the combination of butyl hexanoate 

 and ammonium carbonate in the presence as 

 well as the absence of food was the trap 

 treatment that caught the most immature flies 

 (Figure 2), captures were well below those of 

 mature flies on traps with lures. Responses of 

 wild flies were similar to those of released 

 mature flies (Figure 3). Again, captures on 

 traps having butyl hexanoate alone were 

 nearly four-fold greater than captures on 

 unbaited traps. Again, addition of ammonium 

 carbonate did not enhance trap capture. 



Conclusions 



Our results support the combined use of 

 sticky red spheres and butyl hexanoate lures as 

 an alternative to insecticides to control AMF. 

 Addition of ammonium carbonate lures did not 



enhance captures of released mature flies or 

 wild flies, and its slight enhancement of trap 

 captures of immature flies was not great 

 enough to justify its use. Presence or absence of 

 natural food in orchard blocks had little 

 detectable effect on response patterns of either 

 released mature, released immature, or wild 

 flies. Response patterns of wild flies seem to 

 indicate that their populations consisted 

 mainly of mature flies. 



Our findings support use of a behavioral 

 control strategy based on the employment of 

 visually attractive red spheres together with 

 butyl hexanoate as an odor lure. 



Acknowledgments 



We are grateful to Stanley Baj, Dana Clark, 

 and the Peck brothers for generously allowing 

 use of their orchards. This work was supported 

 by USDA CSRS NRI grant 95-37313-1890 and 

 Cooperative agreement 94-COOP-1-0482. 



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Fruit Notes, Volume 62 (Number 3), Summer, 1997 



