Effects of Elevated CO_2 Concentration on Growth and Development of Lymantria dispar (Lepidoptera:Lymantridae),as well as on Activities of Detoxifying Enzymes and Protective Enzymes in the Body
【Objective】The present paper aimed to study effects of elevated CO_2 concentration on the growth and development,nutrient utilization and in vivo detoxifying enzymes and protective enzymes of the serious forest defoliator,Lymantria dispar (Lepidoptera:Lymantridae).【Method】The different CO_2 concentrations (397,550 and 750 muL·L~(-1)) were applied in the closed CO_2 artificial climate chamber,and the effects on growth and development of L.dispar were measured,and the effects on activities of detoxification enzymes and protective enzymes of L.dispar were determined by spectrophotometry.【Result】The elevated CO_2 concentration was able to prolong the egg hatching period of L.dispar,increased fecundity and hatching rate.At the same time,the elevated CO_2 concentration significantly prolonged the total larval developmental period,however,it had no significant effects on pupae and adult duration.Increased CO_2 concentration decreased the relative feeding rate and the approximate digestibility,but increased the food utilization rate and the conversion rate of digested food by L.dispar.The activities of superoxide dismutase (SOD) and catalase (CAT) in L.dispar larval body were significantly induced by 750 muL·L~(-1) of CO_2 concentration,and increased by 32.05% and 13.47% compared with that at 397 muL·L~(-1) CO_2 concentration,respectively;With the increase of CO_2 concentration,the activities of cytochrome P450 increased by 78.79% and 93.50% under 550 muL·L~(-1) and 750 muL·L~(-1) CO_2,respectively,compared with that at 397 muL·L~(-1) CO_2.The GST activities were the highest under 550 muL·L~(-1) CO_2 concentration,which was 71.03% and 50.00% higher than those in 397 muL·L~(-1) and 750 muL·L~(-1) treatment groups,respectively.【Conclusion】The elevated CO_2 concentration can affect the growth and physiological metabolism of the L.dispar larvae.At the same time,L.dispar can resist the high concentration of CO_2 through changing the developmental duration,increasing the food utilization and transformation,and changing the activities of detoxifying enzymes or/and protective enzymes to achieve the purpose of maintaining life.