关键词: 粘虫, 变温, 卵巢管, 能源物质, 糖代谢, 脂代谢

Abstract: 【Aim】 This research aims to clarify the relationship between fluctuating temperature and development and fecundity of  Mythimna separata  (Walker), and the change pattern of primary energy substances in this insect under daily alternating temperatures. 【Methods】 The eggs of M. separata were reared at two constant temperatures (25℃ and 30℃) and the fluctuating temperature (30/20℃) with the photoperiod 14L:10D, respectively. The development and fecundity at the constant temperature 25℃ and the fluctuating temperature 30/20℃ were observed and recorded. The contents of energy substances (glycogen, trehalose, and triglyceride) and the activities of the primary enzymes in energy metabolism, i.e. trehalase (TRE), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), glycerol 3-phosphate dehydrogenase (GPD) and 3-hydroxyacyl-coenzyme A dehydrogenase (HOAD), in the 3rd instar larvae, 6th instar larvae, pupae and 1-day-old adults reared at 30℃ and 30/20℃were measured.【Results】 The development of ovarioles of the 1-day-old female adults at 25℃ delayed and the number of eggs laid per female were higher as compared with those at the fluctuating temperature 30/20℃. The contents of glycogen, trehalose, and triglyceride were the highest at the pupal stage and lower at the adult stage. The contents of glycogen, trehalose, and triglyceride contents at fluctuating temperature (30/20℃) were significantly higher than those at the constant temperature (30℃), while the triglyceride content had no significant difference at both the 6th instar larval stage and the pupal stage between the two temperatures. Temperature fluctuations significantly influenced the activities of the four metabolism enzymes. 【Conclusion】 Temperature fluctuation has significant impacts on the development and fecundity of M. separata. The metabolism in the growth and development of M. separata is primarily glucose-based. The daily fluctuating temperature accelerates the metabolism of glucose, relieves lipid metabolism at specific developmental stages and benefits the accumulation of energy substances in M. separata.

Key words: Mythimna separata, fluctuating temperature, ovariole, energy substance, glycometabolism, lipometabolism