of control treatments in which oil alone was applied . If Acknowledgements 

 an Experimental Use Permit for Dimilin continues to 

 be granted for use on pears in Massachusetts, as it was 

 in 1988 and 1989, we encourage growers who have had 

 trouble controlling psylla to try using Dimilin, pro- 

 vided they are willing to make 2 pre-bloom applications 

 at 12 oz per acre (together with oil) beginning in early 

 or mid-April and a post-bloom application in late May. 



We thank Paul Bohney and UniRoyal Chemical 

 Co. for supporting this work. We also thank all of the 

 participating applicators: Stanley Baj of Atkins Farm 

 in Belchertown, Keith Bohney of Westford, David Ch- 

 eney of Brimfield, and Tony Rossi of the Horticultural 

 Research Center in Belchertown. 



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Advancements in Second-stage Apple IPM: 

 Substituting for "Sticky" on Baited Red 

 Spheres 



Jian Jun Duan, Max P. Prokopy, Patricia Powers, 

 and Ronald J. Prokopy 



Department of Entomology, University of Massachusetts 



Recently, we reported results of a 3-year pilot 

 project in commercial apple orchard blocks using sec- 

 ond-stage IPM techniques [Fruit Notes 55(l):4-9]. One 

 of the keystone practices was the use of sticky red 

 spheres baited with synthetic apple odor to intercept 

 immigrating apple maggot flies (AMF) on perimeter 

 apple trees before they could penetrate the orchard 

 interior. We concluded that for such an interception 

 system to be successful on a broad-scale commercial 

 level, certain improvements would be necessary. One 

 improvement concerned enhancing the attractiveness 

 of the red spheres, results of which are reported in 

 FruitNotes 54(4):18-19. Here, we describe initial tests 

 aimed at replacing the sticky coating used in capturing 

 and killing AMF with a mixture containing a fly feeding 

 stimulant, a pesticide, and a residue-extending agent. 

 Our hope is to discover an effective mixture of these 

 components so that a fly alighting on a treated sphere 

 would be stimulated to feed and thereby ingest enough 

 pesticide to be killed rapidly, before it could lay eggs. 



Methods Used 



All tests reported here were carried out in the 

 summer of 1989. A potted apple tree was placed in each 

 of 2 large field cages. Two unbaited, 8-cm, red spheres 

 of the same treatment were hung on each tree. For 

 each trial, a mature AMF male was released on a leaf 

 midway between the spheres and followed until it 

 visited a sphere, left the tree without visiting a sphere, 



or else 5 minutes had elapsed without the fly visiting a 

 sphere. The length of each visit was recorded. After 

 departing a sphere, the fly was captured and kept in a 

 laboratory cage to determine whether it was alive or 

 dead after 24 hours. We tested males because females 

 were used in other projects and thus were not avail- 

 able. This fact may be a shortcoming of the work 

 reported here, because we want to control females in 

 orchards. 



Fly Feeding Stimulants 



Table sugar (sucrose) and corn syrup (sucrose plus 

 some other types of sugar) are known to be excellent 

 feeding stimulants for house flies. In preliminary 

 laboratory tests, we found that both stimulated AMF to 

 feed, as long as the concentration was 2% or greater. 

 Hence, we used one or the other in mixture with 

 pesticide and residue-extending agent in our field cage 

 tests. Presently we are conducting laboratory tests in 

 search of even more effective feeding stimulants. 



Pesticides 



In our first experiment, we evaluated the effective- 

 ness of 4 pesticides currently labelled for orchard use: 

 the synthetic pyrethroids Pounce™ 3.2 EC and As- 

 ana™ 1.9 EC, the organophosphate Guthion™ 50 WP, 

 and the carbamate Lannate™ 1.8 SL. These materials 

 are among the most insect-toxic members of the 3 



Fruit Notes, Spring, 1990 



17 



