THE PENETRATION OF THE INSECT CUTICLE BY ISOMERS OF BENZENE HEXACHLORIDE
1951; Wiley; Volume: 38; Issue: 3 Linguagem: Inglês
10.1111/j.1744-7348.1951.tb07827.x
ISSN1744-7348
AutoresG. M. Armstrong, F. R. Bradbury, H. Standen,
Tópico(s)Plant Surface Properties and Treatments
ResumoThe penetration of the α‐, β‐, γ‐ and δ‐isomers of benzene hexachloride through the insect cuticle has been studied by a micro‐colorimetric technique. Grain weevils were exposed for varying periods to deposits of pure isomers of benzene hexachloride on filter‐paper. The amounts of each isomer picked up by the insects were determined as two fractions, one ‘outside’ representing that which could be removed by cold methanol washing, and the other ‘inside’ recovered after decomposing the insects with nitric acid. The results show that the amounts of each isomer taken up by the insects are in the approximate ratio of their solubilities in hydrocarbon solvents, and that the y‐isomer penetrates through the outer layers of the insect integument much more rapidly than the other three isomers tested. On the basis of these results it is concluded: (i) that the first stage of pick‐up of insecticide by the insects is simple solution of the insecticide in the outer waxy covering of the epicuticle; and (ii) that structural effects play an important part in the penetration through the insect cuticle as well as in toxic effects at the site of action.
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