355 



695. , and Adkisson, P. L. 1969. Laboratory tests of insecticides for boll- 

 worm, tobacco budworm and boll weevil control. Tc v. Agric. Exp. Stn. 

 Prog. Rep. 2670-2674, pp. 10-14. 

 Laboratory tests were conducted to determine insect.lcide toxicities to bollworms, 

 Heliothis zea (Boddie), tobacco budworm, Heliothis virescens (F.) and boll 

 weevils, Anthonomus grandis Boh. Methyl parathion, EPN and Azodrin or mixtures 

 of these materials with each other proved highly toxic to bollworras. In addi- 

 tion, mixtures of certain chlorinated hydrocarbon insecticides with methyl para- 

 thion killed high percentages of the bollworms. The chlorinated hydrocarbon 

 insecticides tested without the addition of organophosphorus insecticides were 

 ineffective. The tobacco budworm population in the Lower Rio Grande Valley, 

 and perhaps near College Station, has apparently developed a low-level resistance 

 to the methyl parathion and Azodrin. Large dosages of these two insecticides 

 were necessary to kill the tobacco budworms in laboratory tests involving sprayed 

 cotton plants. In addition, LDcf^ values for methyl parathion as computed from 

 dosage mortality lines indicated that the tobacco budworm has developed a 2.0- 

 2.5-fold increase in resistance to methyl parathion during the past year. Simi- 

 lar increases by the budworm to Azodrin were also evident. There was no evidence 



that the bollworm has developed resistance to any of the organophosphorus in- 

 secticides. The organophosphorus insecticides were the materials most toxic 

 to the boll weevil. Chlorinated hydrocarbon insecticides were relatively in- 

 effecitve against the boll weevil; however, their toxicities were increased 

 when they were used in combination with certain organophosphorus compounds. 



697. Nettles, W. C, Jr. 1972. Toxic sugars and longevity of Anthonomus grandis , 



J. Insect Physiol. 18: 1107-1113. 

 Toxic sugars (D-arabionse, L-rhamnose, and L-sorbose) were fed to adults of 

 the boll weevil, Anthonomus grandis . Based on lonppvity as a criterion, ara- 

 bionose was the most toxic of the three sugars. Vhen fed to newly emerged 



