115 



weevils. J. Assoc. Off. Anal. Chem. 61: 629-635. 

 A simple and convenient gas-liquid chromatographic procedure involving 

 electron capture detection is described for determining diflubenzuron (N- 

 [ [ (4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide) in pond water and 

 for determining the uptake of penfluron (trifluoromethyl analog of diflu- 

 benzuron) by boll weevils sexually sterilized by this compound. Both com- 

 pounds were quantitatively converted to their respective N-(trifluoroacetyl) 

 anilines by treatment with trifluoroacetic anhydride and pyridien in benzene 

 at 50-60*'C. In boll weevil analyses, the procedure was quantitative for 

 penfluron at concentrations involving microgram quantities, background 

 interference necessitated a thin layer chromatographic cleanup prior to 

 derivatization. This modification enabled the determination of 100 ng/weevil. 

 Analysis for diflubenzuron in natural pond water gave excellent results. For 

 example, diflubenzuron at 2, 0.2, and 0.02 ppm in pond water was recovered 

 at 95, 82, and 98%, respectively. A mechanism describing the reaction is 

 proposed. 



215. Dominguez, R. Y. 1977. Effect of different climatic conditions on dis- 

 tribution of Anthonomus grandis in Mexico. Folia Entomol. Mex. 36: 34-35. 

 (Itl Spanish). 

 The regions in which the boll weevil is considered to be an important pest are: 

 El Fuerte and Guasane in Sinaloa; Matoinoras, Mante and Tampico in Tamaulipes; 

 Apetzingan in Michoacan; Iguala in Guerrero; in the States of Morelas and 

 Oaxaca, in Chiapas, Tapachila and Tuxtla Gutienez. It is r.r ^ considered an 

 insect of importance: in Sonora, south of Nogales; in Chll/i'.hua, Valle de 

 Juaez, Delicias, Meaqui, Ojinaga and Presidio, in Derrango, Bermejillo and 

 Nazeis, in Sinaloa, Villa Union; in Nayarit, Valle de Santiago Ixcuintla; 

 in Jalisco, Ajutla; and in San Luis Patosi and Morelos. 



