Field Experiments with Insecticides on Cotton for Control of the Boll Weevil, Bollworm, and Cotton Leafworm in 19611

Abstract

Stauffer R-1504 compared favorably in control of the boll weevil ( Anthonomus grandis Boheman) with Sevin or Guthion. Geigy 30494, Methyl Trithion, and Bayer 41831 were as effective as methyl parathion. In two experiments endrin plus DDT gave control equal to that obtained with toxaphene plus DDT, but not equal to that obtained with Sevin or Guthion. Dusts or sprays of toxaphene or Strobane plus DDT were equally effective against boll weevils and bollworms ( Heliothis zea (Boddie)) but were less effective than Guthion plus DDT against boll weevils. At the dosages used, Shell SD-4402 was as effective against bollworms as Sevin or endrin, Bayer 41831 compared favorably with Sevin, and Dibrom gave poor control. Zectran was as effective as methyl parathion against cotton leafworms (Alabama argillacea (HUbner)). Trithion and Stauffer R-1504 were less effective. The chemical definitions of the insecticides with proprietary names mentioned above are as follows: Bayer 41831 ( O,O -dimethyl O -(4-nitro- m -tolyl) phosphorothioate) Dibrom® (1,2-dibromo-2,2-dichloroethyl dimethyl phosphate) Geigy 30494 ( O,O ,-dimethyl S -(2,.5-dichlorophenylthiomercaptomethyl phosphorodithioate) Guthion® ( O,O -dimethyl S- ( 4-oxo-1 ,2,3-benzotriazin-3( 4H)-ylmethyl) phosphorodithioate) Methyl Trithion ( O,O -dimethyl S-p-chlorophenylthiomethyl phosphorodithioate) Sevin® (1-naphthyl N-methylcarbamate) Shell SD-4402 (1,3,4,5,6,7,8,8-oetachloro 3a,4,7 ,7a-tetrahydro-4,7-methanophthalan) Stauffer R-1504 ( O,O -dimethyl S-phthalimidomethyl phosphorodithioate) Strobane® (terpene polychlorinates (65% chlorine)) Trithion® ( O,O -diethyl S- p -chlorophenylthiomethyl phosphorodithioate) Zeetran ® (4-dimethy lamino-3,5-xylyl methylcarbamate).