f estiva Mues., as well as to the oriental fruit moths. When adults of 

 these species were exposed to apples washed as described above, there 

 was no greater mortality than in the check lots exposed to unsprayed 

 apples. The propagation of oriental fruit moths and their parasites 

 exposed to washed apples was as high as in the no -spray checks. During 

 the many months that apples with DDT residues have been washed by 

 this process and used in routine parasite production, there has been no 

 evidence of objectionable toxicity. 



On apples picked 4 days after being sprayed with parathion and 

 placed in comnnercial cold storage, highly toxic residues persisted for 

 many months and the apples proved generally undesirable for rearing 

 work. There was a high mortality among oriental fruit moths and 

 several species of parasites of the fruit moth when exposed with un- 

 washed apples. The washing procedure that served to reduce DDT to 

 tolerated levels failed to do so with parathion residues. After 32 weeks 

 of storage these parathion- sprayed apples were analyzed, and sm.all but 

 detectable residues of parathion were found. Samples were given the 

 custonnary 30-second wash in benzene-isopropyl alcohol. These apples 

 were used in propagating A. f estiva and P. grapholithae , and there was 

 no evidence of toxicity to the breeding parasites. However, when 

 oriental fruit moths were exposed with the washed apples in egg- 

 deposition cages, there was a high mortality, which did not appear 

 until after 96 hours of exposure. 



.."> 



•i^>-t ' 



Figure l.--Bean hamper with small green apples packed 

 for long storage. 



