Electron Microscopic studies on the antennal sensilla and the pheromone-producing glands of two important oil seed pests
Sensory mechanisms underlying insect chemical communication have been given considerable attention in recent years. A study on the ultrastructural details of the antennal appendages and the pheromone producing structures of Achoea janata L. and Ophiusa algira were studied with scanning electron microscope in order to understand the mechanisms of olfactory perception and pheromone release.For fixation of pheromone producing glands of A.Janata and O.Algira the posterior region of the abdomen was pressed sufficiently and flooded with carnoys fluid for complete excedation of the 9th abdominal along with the ovipositor. The above specimens as well as the antennal appendages were then fixed in 4% glutaraldehyde in phosphate buffer of 7.2 pH dehydrated in increasing grades of ethylalcohol and critical point dried. The specimens were then coated with gold in vacuum evaporator and observed in a Hitachi S-520 evaporator and observed in a Hitachi S-520 SEM operated at 20KV.