215 



14-20 Ifold, 3rd; 4-7 fold, 4th; and 14 fold increase to 3 fold decrease, 5th. 



416. ; Taft, H. M. ; and James, W. 1975. Reference LD^q values for some 

 insecticides against the boll weevil. J. Econ. Entomol. 68: 189-192. 



The standard method (topical application) of determining resistance in Anthonomus 

 grand is Boheman adopted by the Entomological Society of America was used to esta- 

 blish LD50 values for 6 experimental insecticides and 16 chemicals or chemical 

 combinations. These values can serve as reference standards that may be used to 

 detect changes in susceptibility. The average LD^q's ranged from 0.052 ug/weevil 

 for methyl parathion to 39,490 for carbaryl. Also, the LDcq's obtained for toxa- 

 phene + DDT, methyl parathion, and carbaryl by the standard method were compared 

 with the LC_»'s obtained with an immersion method and a dry film method. The 

 dry film method appeared more promising for a field test kit. 



417. ; Taft, H. M. ; and James, W, 1977. Tobacco budworm, bollworm, and 

 boll weevil: effectiveness of newly developed experimental insecticides 

 on cotton in the Southeast. J. Econ. Entomol. 70: 725-726. 



In replicated field tests perraethrin (FMC-33297) (3-(phenoxyphenyl) methyl cIs , 

 trans- (±)-3-(2,2-dichloroethenyl) , -2, 2-dlmethylcyclopane-carboxylatc, Shell 

 SD-43775 (cyano(3-phenoxyphenyl) methyl 4~chloro-alpha- (1-methylethyl) (benzene- 

 acetate), and Shell SD-41706 (cyano (3-phenoxy-phenyl) methyl 2, 2, 3, 3-tetra- 

 methylcyclopropane-carboxylate) gave outstanding control of the b&ll weevil, 

 Anthonomus grandis Boheman, and the bollworm complex, Heliothis zea (Boddie) 

 and H. virescens (F.). Bay NTN-9306 (0-ethyl[4-methylthio) phenyl] S-propyl 

 phosphorodithioate) plus azinphosmethyl gave control equal to or better than 

 the treated control, toxaphene + methyl parathion + chlordimeforra. Rohm and 

 llaas RH-218 (0-ethyl S-propyl 0-2,4,6-trichlorophenyl) phosphorothioate) + 

 toxaphene gave better control of Heliothis spp. than the treated control but 

 produced low yields and was phytocoxlc. In all tests, correlation analysis 



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