Evaluation of Soil Insecticide Treatments for Control of Cyclodiene-Resistant Southern Corn Rootworms2

Experiments to control the southern corn rootworm, Diabrotica undecimpunctata howardi Barber, were carried out in southeastern Virginia during 1962.Sixty-five different formulations of 26 compounds were tested as soil-band treatments at pegging time on Virginia jumbo-type peanuts. Nine compounds: diazinon; Zinophos (O,O-diethyl O-2-pyrazinyl phosphorothioate); GC-4072 (2-chloro-1-(2,4-dichlorophenyl)vinyl diethyl phosphate); phorate; AC-43064 (2-(diethoxyphosphinothioylimino)- 1,3-dithiolane); Bayer 25141 (O,O-diethyl O-[p-(methyl- sulfiny1)phenyl] phosphorothioate); Bayer 39007 (o-isopropoxyphenyl methylcarbamate); UC-10854 (m-isopropylphenyl methyl carbamate); and UC-8305 (P-chloro-2,4,dioxa-5-methyl P-thiono-3-phosphabicyclo(4.4.0)decane), applied in granular form as soil-band treatments during mid-July effectively controlled a cyclodiene-resistant population of the southern corn rootworm. Emulsifiable concentrate treatments were ineffective. Root-worm control resulted in an increase in yield and in percent of sound mature kernels.