L'oeuf de Bruchidius atrolineatus (Pic) et son système de fixation

Abstract

Scanning electron microscope studies of eggs of Bruchidius atrolineatus were made and the system of egg fixation on cowpea pods (Vigna unguiculata Walp) was described. The egg is fusiform and asymmetrical. Its upper part is convex and polygonal structures are present. Its lower surface is flat and exhibits small protuberances. The convex side is 8 μm thick whilst the flat side is only 1 μm thick. A strengthened band-like zone separates the convex side from the lower part of the egg. When laid, the egg is coated with a sticky mucus-like substance. This substance hardens when entering stomata of the pods. An efficient egg-fixation system thus covers the stomata.