and BioControl Theory|
Russia, 199034, St.-Petersburg, Zoological Institute.
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diapause in Coccinellidae (Coleoptera)
Project conducted by Drs. V.A. Zaslavski, V.P. Semyanov and N.P. Vaghina since 1991.
An imaginal (reproductive) diapause, peculiar to the aphidophagous lady beetle Coccinella septempunctata L. can be induced either by short-day photoperiod or by lack of aphids as prey. The joint action of these diapause-inducing factors provokes a very stable diapause which cannot be caused by any factor alone. This evidences a strong interaction between photoperiodic and alimentary reactions, testifying to a certain similarity of their physiological backgrounds.
The lack of aphids in the diet seems to be only external factor that induces the diapause in laboratory stock of Harmonia sedecimnotata originating from southeastern China. This diapause lasts several months, but it may cease quickly every time provided the aphid diet is resumed. The rate of reactivating which is detected by the onset of egg-laying depends on the number of aphids in the daily meal. The experiments performed on effects of the aphid numbers made is possible to differentiate the common metabolic and specific signal roles of aphids as a food of specialized aphidophagous coccinellid beetle. The cue factor(s) acts most likely via chemoreception. The developmental response to specific food was as strong and precise as the well known responses to the photoperiod.
(those published or translated in English are indicated by blue color)
Semyanov V.P., N.P.Vaghina. 2001. The odor of aphids as a signal for termination of the trophic diapause in the lady beetle Harmonia sedecimnotata (Fabr.)(Coleoptera,Coccinellidae). Zoological Sessions. Annual reports 2000. Trudy ZIN RAS 289: 161-166.
Semyanov V.P. & Vaghina N.P. 1999. Trophic diapause: effect on fecundity and longevity of Harmonia sedecimnotata Fabr. (Coleoptera, Coccinellidae). In: Zoological Sessions. Annual Reports 1998. Trudy ZIN RAS 281:. 87-89.
Zaslavski V.A., Semyanov V.P. & Vaghina N.P. 1998. Food as a cue factor controlling adult diapause in the lady beetle, Harmonia sedecimnotata (Coleoptera, Coccinellidae). Zool. Zhurn. 77: 1383-1388 (in Russian).
Zaslavski V.A. & Vaghina N.P. 1996. Joint and separate effects of alimentary and photoperiodic induction of diapause in Coccinella septempunctata (Coleoptera, Coccinellidae). Entomol. Obozr. 76: 1025-1031 (in Russian).