MINERAL CONCENTRATIONS WITHIN CELLS OF GALLS INDUCED BY HEMADAS NUBILIPENNIS (HYMENOPTERA, PTEROMALIDAE) ON LOWBUSH BLUEBERRY - EVIDENCE FROM CRYOANALYTICAL SCANNING ELECTRON-MICROSCOPY

Cryoanalytical scanning electron microscopy was used to examine cellul ar concentrations of K, P, S, Mg, Ca, Fe, Cu, Ni, and Au in a planed s ection of an insect gall induced by Hemadas nubilipennis on shoots of lowbush blueberry. Levels of K varied throughout tissues of the gall, with the highest levels within the cytoplasmically dense nutritive cel ls lining the larval chambers, storage nutritive cells, and peridermal cells. It is postulated that K increases the osmotic potential and si ze of nutritive cells, thereby facilitating larval feeding. Nutritive cells also contained elevated levels of P and S. Levels of Cu, Ni, Fe, and Au were elevated in epidermal tissues, especially near the stomat a.