ABSTRACT

X avier B elles Institut de Biologia Molecular de Barcelona (CSIC) Jordi Girona 18, 08034

Barcelona, Spain, e-mail: xbragr@cid.csic.es

L INTRODUCTION

The vitellogenic role of juvenile hormone (JH) was one of the historical discoveries made by V.B. Wigglesworth on his favourite model, the blood-sucking bug Rhodnius prolixus (Wigglesworth, 1936). Classical experiments of removal of the corpora allata, the source of JH, followed by replacement therapy and monitoring of oocyte growth, soon led to description of the vitellogenic role of JH in a number of other insect species (see Engelmann, 1983). Although the generalization of the concept of vitellogenesis controlled by JH was broken in 1975, when Hagedom and associates reported that in mosquitoes vitellogenesis is directed by ecdysteroids (see Hagedom, 1985), there are still many insect species in which this process has been shown to be JH-dependent.