498 



A laboratory strain of the tobacco budworm, Hellothls vlrescens (F.). was 



generally more susceptible to topical application of the els-, and trans- 



geometrical isomers of (3-phenoxyphenyl) methyl of (2,2-dichloroethenyl)-2.2- 



dimethylcyclopropanecarboxylate than field-collected strains. The cis- isomer 



was more active than the trans- isomer. Low levels of the trans- isomer mixed 



with the cis-isomer appeared antagonistic to the activity of the cis- isomer 



against the laboratory strain, but high levels (60 and 75%) appeared syner- j 



gistic against the laboratory strain. The boll weevil, Anthonomus grandis 



Boheman, was equally sensitive to both isomers and to the various mixtures 



of the isomers tested. In field trials, FMC-33297 (60 trans : 40 ci£) applied 



at the rates of 0.1-0.2 lb/acre was effective against the boll weevil, tobacco 



budworm, bandedwing whitef ly, Trialeurode s abutilonea (Haldeman) , and cotton 



fleahopper, Pseudatomoscelis seriates (Reuter), and also against the predator 



complex. 



985. ; McGarr, R. L.; Longoria, R. R. ; and Nosky, J. B. 1970. Toxicity 

 of EPN, Accothion, and certain chlorinated hydrocarbons to certain 

 cotton insects. J. Econ. Entomol. 63: 1568-1573. 

 In tests of candidate insecticides against some cotton insects, ultra low volume 

 (ULV-64 oz/acre or less) sprays of EPN (0-ethyl 0-p-nitrophenyl phenylphospho- 

 nothioate) were more effective than conventional sprays in field tests against 

 boll weevils, Anthonomus grandis Boheman; tobacco budworms, Heliothis virescens 

 (F.); bollworms, H. zea (Boddie) ; and pink bollworms, Pectinophora gossypiella 

 (Saunders). ULV sprays of Accothion® (0, 0-dimethyl 0-4-nitro-m-tolyl phosphoro- 

 thioate) were effective against the pink bollworm but not against the tobacco bud- 

 worm and bollworm, and the percentages of loss from the cotton leaf after applica- 

 tion as a conventional spray were about the same (88-79%) 4 days after application, 

 whether the pesticide was applied at rates of 1.12 or 17.6 kg/hectare. Isobenzan 

 and Isodrin, applied as conventional sprays, were the most toxic of the cyclodiene 



