Abstract: 【Aim】 This study aims to clarify the characteristics of main physiological and biochemical change in Galeruca daurica adults at different oversummering stages so as to lay a foundation for revealing the oversummering mechanism. 【Methods】 The contents of total sugar, trehalose, glycogen, lipid and water in G. daurica adults at different oversummering stages (pre-oversummering, during oversummering and post-oversummering) were determined by anthrone-sulfuric acid and methanol-chloroform methods, respectively, and the total protein content was detected by Coomassie brilliant blue G-250 method. 【Results】 The contents of total sugar, water and total protein in G. daurica adults were significantly higher at the pre-oversummering stage (26.81 μg/mg, 77.47% and 63.17 μg/mg, respectively) and post-oversummering stage (26.41-26.85 μg/mg, 75.29%-76.65% and 59.53-64.93 μg/mg, respectively) than during oversummering (18.77-21.14 μg/mg, 61.50%-67.20% and 39.82-52.54 μg/mg, respectively), whereas the change trend of glycogen contents was the opposite, being 8.43 μg/mg at the pre-oversummering stage, 5.91-6.14 μg/mg at the post-oversummering stage and 10.18-11.58 μg/mg during oversummering, respectively, and the content of lipid was significantly less at the post-summering stage (11.48%-11.65%) than at the pre-oversummering stage (42.48%) and during oversummering (36.05%-64.79%). The contents of lipid and total protein decreased gradually in G. daurica adults during oversummering, while the water, total sugar and glycogen contents showed no obvious change. The trehalose content in G. daurica adults at different oversummering stages fluctuated greatly from 2.66 μg/mg to 25.31 μg/mg. 【Conclusion】 Lipid and glycogen are the main energy materials of G. daurica adults during oversummering.

Key words: Galeruca daurica; oversummering, diapause, carbohydrate, glycogen, trehalose, protein, lipid