| Popis: |
Insect corpora allata (CA) synthesize juvenile hormone (JH). This hormone regulates development and reproduction (for reviews see [1, 2]). In Orthoptera, such as Locusta migratoria ovarian growth and vitellogenesis are well known to be regulated by JH. The oocytes grow in synchrony and several batches of eggs are formed. These gono-trophic cycles are closely correlated with cyclic changes of CA activity [3,4]. In young females JH biosynthesis increases through previtellogenesis and reaches a maximum during vitellogenesis. At the end of an oogenic cycle JH synthesis declines to low previ-tellogenic levels until the onset of the next oogenic cycle. Thus, in locusts the regulation of biologically active JH occurs rather at the level of synthesis than at the level of transport, sequestration, catabolism, or excretion [5]. |
