西伯利亚蝗气门结构及呼吸代谢对高温胁迫的响应

【目的】掌握西伯利亚蝗Gomphocerus sibiricus的气门结构和呼吸代谢应对高温胁迫的响应策略。【方法】运用扫描电镜观察西伯利亚蝗气门超显微结构,多通道昆虫呼吸仪测定18~42℃处理下西伯利亚蝗的O_2吸收率、CO_2释放率、代谢率和呼吸商。【结果】西伯利亚蝗共有10对气门,胸部2对,腹部8对,呈圆形或椭圆形,内侧着生有筛板,呈刺凸状,分布密集。18~42℃范围内,随温度升高,西伯利亚蝗呼吸代谢呈先上升后下降的趋势。18℃时西伯利亚蝗雌雄成虫的O_2吸收率、CO_2释放率和代谢率值显著小于其他温度下的相应值(P<0.05),雌虫分别为0.0022 m L/min、0.0019 m L/min和0.0210 m L/(g·min),雄虫分别为0.0016 m L/min、0.0016 m L/min和0.0236 m L/(g·min);21~27℃范围内,西伯利亚蝗雌雄成虫的呼吸代谢变化平稳,超过30℃呼吸代谢各指标值迅速上升,至36℃时雌雄成虫的O_2吸收率和代谢率值均显著大于其他温度下的相应值(P<0.05);雌虫分别为0.0071 m L/min和0.0592 m L/(g·min),雄虫分别为0.0089 m L/min和0.1108 m L/(g·min),39℃时CO_2释放率显著大于其他温度下的相应值(P<0.05),雌雄成虫分别为0.0074 m L/min和0.0067 m L/min。【结论】依据西伯利亚蝗呼吸代谢随温度变化特征可以判断,随气候持续变暖,西伯利亚蝗仍将是新疆高山、亚高山草原的重要致灾类群。

Stigma structure and response of respiratory metabolism of Gomphocerus sibiricus to high temperature stress

[Objectives] To explore the stigma structure and response of the respiratory metabolism of Gomphocerus sibiricus to high temperature stress. [Methods] Stigma structure was observed via scanning electron microscope (SEM), and O2 uptake rates, CO2 release rates, metabolic rates, and respiratory quotients, measured with a multi-channel insect respiration apparatus (Sable Systems, USA). Respiratory measurements were made a 3℃ intervals within a temperature gradient of 18-42℃. [Results] G. sibiricus has ten pairs of circular, or near circular, shaped stigmata. Filter apparatus inside stigma were clustered. The respiratory metabolism of G. sibiricus first increased, then decreased, between temperatures from 18 to 42℃. O2 uptake rates, CO2 release rates and metabolic rates of male and female adults at 18℃ were significantly lower than those at the other temperatures (P<0.05);corresponding values for females were 0.0022 mL/min、0.0019 mL/min and 0.0210 mL/(g×min), whereas those for males were 0.0016 mL/min、0.0016 mL/min and 0.0236 mL/(g×min). The respiratory metabolism of male and female adults underwent little change between 21 and 27℃, but respiration increased rapidly at temperatures over 30℃. Metabolic rates and O2 uptake rates of male and female adults at 36℃ were significantly higher than those at other temperatures (P<0.05);corresponding values for females were 0.0592 mL/(g×min) and 0.0071 mL/min, and for males were 0.1108 mL/(g×min) and 0.0089 mL/min. However, CO2 release rates of male and female adults were 0.0074 mL/min and 0.0067 mL/min, respectively, at 39℃;significantly higher than at other temperatures (P<0.05). [Conclusion] G. sibiricus is likely to remain an important pest in Xinjiang alpine and subalpine grasslands despite global warming.