384 



752. Reeves, B. G.; Wilkes, L. H.; Ridgway, R. L.; and Lindqulst, D. A. 

 1967. Applying systemic insecticides to cotton: on equipment evaluation. 

 Agrlc. Eng. 48: 646-647. . ' • 



Laboratory studies indicate that applying certain systemic insecticides to the 

 stem of cotton plants rather than to the soil gives up to 74 percent greater 

 efficiencies. Stem treatments with systemic insecticides indicate good control 

 of aphids, spider mites, cotton fleahoppers, lygus bugs, boll weevils, bollworms, 

 and tobacco budworms. Large-scale field trials, however, have been infrequent 

 because of a scarcity of mechanized equipment. In 1964, we built an experimental 

 applicator that has two wood discs 6-in. in diameter and 1 1/2 in. thick. Discs, 

 covered with sponge rubber, reached both sides of the cotton row. Rotating in a 

 horizontal plane near the ground, these discs transferred the insecticide to the 

 plant stems. In 1965 a more detailed research project was conducted to evaluate 

 rotary and stationary brushes and lateral spray in the application of systemic 

 insecticide to the main plant stems. In these further field tests the rotary 

 brush applicator demonstrated effective control of cotton fleahoppers and lygus 

 bugs. This method of application greatly reduces the hazards of drift and 

 atmospheric contamination; its application efficiency is significantly above 

 levels obtained with conventional methods of systemic insecticide applications. 



753. Reiman, J. G., and Flint, H. M. 1967. Irradiation effects on midguts 

 and testes of the adult boll weevil, Anthonomus grandis , determined by 

 histological and shielding studies. Ann. Entomol. Soc. Ara. 60: 298-308. 



Histological studies demonstrated that radiation doses considerably below those 

 required for sterilization killed most regenerative cells of boll weevils, 

 Anthonomus grandis Boheman, which resulted in the loss of most or all of the 

 secretory epithelium. Extensive damage to midgut was noted in 1 specimen that 

 received 2000 R and in all those given 4000 R. Shielding experiments showed 

 that when only the head and that part of the thorax anterior to the midgut 



