ABSTRACT
EFFECT OF THURINGIENSIN ON CUTICLE DEVELOPMENT OF IMMATURE STAGES OF Tetranychus urticae Koch. (ACARINA: TETRANYCHIDAE)

Robinson Vargas1, Bruce Chapman2, David R. Penman3
 

The effect of thuringiensin on the ultrastructure of Tetranychus urticae Koch cuticle was studied using an transmission electron microscope (TEM). Thuringiensin was found to affect epicuticle synthesis in larvae, protonymphs and deutonymphs. Its disruptive effects on larval cuticle formation were observed from 12 h onwards, indicating that the effect of the exposure time of mites to thuringiensin is related to the stage of cuticle development. The results suggest that the effects of thuringiensin occur in a relatively short time.

Keywords: thuringiensin, b -exotoxin, Tetranychus urticae, cuticle.
1 Instituto de Investigaciones Agropecuarias, Centro Experimental de Entomología La Cruz, Casilla 3, La Cruz, Chile. Email: rvargas@inia.cl
2 Lincoln University, Department of Entomology and Animal Ecology, P.O. Box 84, Canterbury, New Zealand. Email: chapman@lincoln.ac.nz
3 Landcare Research Ltd., P.O. Box 69, Lincoln, New Zealand. Email: penman@landcare.cri.nz