MSPTM 2019 Annual Scientific Conference
13 - 14 March 2019
InterContinental Kuala Lumpur


Ecdysone during ovarian development in Poikilocerus pictus
Oral Presentation
Scaling Up Efforts in Tropical Disease and Vector Control through Evidence-Based Research
General Topics


Main Author
Presenting Author

Authors' Institution

Department / Institution / Country
Zoology / Dr Harisingh Gaur Vishwavidyalaya Sagar / India1
Abstract Content

Considerable amounts of Ecdysteroids are produced during each ovarian cycle in adult females of Poikilocerus pictus when vitellogenesis is almost completed. The harmonal molecules are synthesised a the end of the maturation of the terminal oocytes during each cycle, at the time when vitellogeneis is almost completed. No synthesis takes place in the absence of ovarian development (allotectomy, ovariectomy) whereas extirpation of the prothoracic glands at the beginning of the adult life does not affect ecdysteroid production. More than 95% of the total ecdysteroid content of female adults can be recovered from the ovaries. In vitro studies show that the ovaries produce ecdysteroids and convert labelled cholesterol into ecdysone.

Microsurgical experiments indicate that this synthesis takes place in the follicle cells surrounding the oocyte. The newly synthesised ecdysteroids do not enter massively into the blood, but pass into the ooplasm where they are progressively converted to polar compounds. As a result, at the end of each ovarian cycle egg-laying corresponds to the disappearance of ecdysteroids from the female insects. The harmonal molecules can easily be recovered from the eggs. A gas chromatographic analysis coupled to mass spectrometry shows that the principal ecdysteroid syntheised by the adult females of Locusta is by far ecdysone. Ecdysterone, the paramount ecdysteroid of the larvae of Locusta is not present in noticeable amounts in the female adults of this species.

Keywords: Poikilocerus; Ecdysone, Hormone; Locusts; Follicle;
Requires Audio or Video system for Presentation?: Yes