Submitted to: Tissue and Cell
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/21/1995
Publication Date: N/A
Interpretive Summary: Sap beetles are harmful pests to fresh and dried fruits and vegetables. They also transmit fungi that produce toxins in corn and other crops. The attractants that these beetles make themselves (pheromones) have been identified, but the structure of the tissues responsible are unknown. Electron microscope studies indicated the glands are of a new type. Active pheromone synthesis is associated with gland size. Now that the tissues that contain the pheromones have been characterized, it will be easier to determine when they are made and to devise methods to interfere with their production. This may, ultimately, lead to new methods for controlling these insects and the problems they cause.
Technical Abstract: The cells that secrete the aggregation pheromone of the male nitidulid beetle Carpophilus freemani are exceptionally large and lie within the body cavity. These secretory cells share many ultrastructural features with cells of other pheromone and defense glands, but they also have several unique features. A deep invagination of the surface of each of these cells acts as the secretory surface for the pheromone. The invaginated surface is highly convoluted and surrounds a narrow cuticular ductule that is connected to the tracheal system. This surface is not covered with microvilli as the comparable surfaces are in other insect secretory cells. Whereas secretory and ductule cells of other insect glands are usually epidermal cells, these cells of nitidulid beetles represent the first pheromone glands in which oenocytes are believed to have been recruited for pheromone production and tracheal cells have been recruited as ductules for these cells.