major classes of orchard-labelled insecticides. For this 

 test, we introduced each pesticide at 100 times the 

 maximum orchard-recommended rate into an aqueous 

 mixture of 2% table sugar and 0.3% Vaporguard™ 

 (used here as a residue-extending agent, obtained from 

 Miller Chemical Co., Hanover, PA). Red-painted, 

 wooden spheres were dipped in each mixture, hung out 

 to dry under protection from rainfall and sunlight, and 

 tested 6 days later. 



The results (Experiment 1 of Table 1) show that 

 just as high a proportion of released AMF (about 60%) 

 visited spheres treated with Pounce, Asana, or Lannate 

 as untreated spheres (without sugar, pesticide, or 

 Vaporguard). A somewhat lesser proportion (47%) 

 visited spheres treated with Guthion, possibly owing to 

 the whitish residue of the wettable powder that par- 

 tially obscured the red color of the sphere. Of the 

 visiting AMF, 60% of those from Lannate died within 

 24 hours, compared with 10% or fewer of those from 

 any other treatment. 



In our second experiment, we evaluated the effec- 

 tiveness of Guthion 1.8 EC, Lannate 1.8 SL, and Lan- 

 nate technical powder. The Guthion EC and Lannate 

 SL were used at 100 times the orchard recommended 

 rate and were mixed in the same proportion with other 

 ingredients as in the first experiment. As before, 

 spheres were dipped in these mixtures. The Lannate 

 technical was mixed at a rate of 2% powder with 56% 

 table sugar, 20% ethanol, 20% water, and 2% of a 

 polymeric thickener (a residue extending agent). This 

 mixture (in paste form) was brushed onto spheres. All 

 spheres were protected from sunlight and rainfall for 

 12 days, and then tested. 



The results (Experiment 2 of Table 1) show that 

 just as great a proportion of released AMF (about 60 to 

 70%) visited each type of treated sphere as untreated 

 spheres, indicating no reduction in AMF attractiveness 

 to spheres as a consequence of treating with pesticide. 

 Of the visiting AMF, 25 and 35% of those from Guthion 

 EC and Lannate SL, respectively, and 70% of those 



18 



Fruit Notes, Spring, 1990 



