COLD STRESS TOLERANCE IN DROSOPHILA - ANALYSIS OF CHILL COMA RECOVERYIN DROSOPHILA-MELANOGASTER

Drosophila melanogaster adults, grown at 21 degrees C, were distribute d in groups of 50 after a light anaesthesia. Culture vials with flies were later submitted to a cold treatment at 0 degrees C. All adults en tered a chill coma; the recovery time was measured at ambient temperat ure. 2. Recovery time was strongly influenced by recovery temperature, with shorter values between 20-25 degrees C. 3. Recovery time increas ed almost linearly with duration of cold treatment. 4. Recovery time w as consistently larger for males than for females. It was highly varia ble among groups and increased with flies' age. 5. Variability among f lies of the same group was always very high, with CVs often over 25%. 6. Chill coma and its recovery seem to imply a modification of the ner vous system, analogous in several aspects to what is observed with usu al anaesthetics such as CO2. (C) 1998 Elsevier Science Ltd. All rights reserved.