Effects of juvenile hormone treatment on phase changes and pheromone production in the desert locust, Schistocerca gregaria (Forskal) (Orthoptera: Acrididae).
The roles of juvenile hormone III (JH III) on phase changes and pheromone production were examined in laboratory-reared gregarious desert locust, Schistocerca gregaria (Forskal). The hormone was applied to 5th instar nymphs and newly emerged adult locusts. Generally, the 5th instar nymphs exhibited a higher sensitivity to hormone treatments than the adults. Hormone applications inhibited pheromone production (as measured by the amounts of phenylacetonitrile released). In addition, JH III had a significant effect on the external colouration and absorbance ratios of the haemolymph pigments. It is concluded that the effects of exogenous JH III on gregarious locusts represent a shift towards the solitarious phase.
Ismail
S H.
SH
Department of Zoology, Faculty of Science, Assiut University, Assiut, Egypt
Hassanali
A
A
Osir
E O.
EO
Tawfik
A I.
AI