Abstract
Examinations were made on the distribution and decomposition of 32P-labeled Baycid in larval tissues after topical application and oral administration to the larvae of Prodenia litura FABRICIUS, and the absorption and decomposition on larvae and pupae of 32P-labeled Baycid topically applied to the insect bodies.
The results summarized were as follows :
1. The partition ratio, (c/c+w)×100, in which c shows radioactivity in chloroform phase and w in aqueous phase, of radioactive materials in various larval tissues was similar between 187 r and 48 r. applications, although the concentration of radioactive materials in various larval tissues was higher when the topically applied doses were higher.
2. The concentration of radioactive materials in larval haemolymph became gradually higher following topical and oral applications in the larvae that died after 24 hours, but the concentration became gradually lower on those that survived.
3. The highest concentration of radioactive materials within various tissues, except haemolymph was detected from alimentary canal at 48 r application, and from fat body and alimentary canal at 187 r application. The partition ratio of fat body after topical application was higher than those of any other tissues.
4. The larvae absorbed almost all topically applied doses within 24 hours, whereas the pupae absorbed less than 17% of the applied doses within 48 hours. The larvae decomposed the absorbed doses more readily than the pupae.
