LdNPV对CO2胁迫下舞毒蛾生长发育及生化酶活性影响

目的以森林害虫舞毒蛾为对象，研究CO₂介导下LdNPV病毒对舞毒蛾生长发育、解毒酶和保护酶的影响。方法利用密闭式CO₂人工气候箱研究了不同CO₂含量（397、550和750 μL/L）条件下饲养的舞毒蛾幼虫，LdNPV对其生长发育指标的影响，并采用分光光度计法测定体内保护酶和解毒酶活性。结果高CO₂含量胁迫下舞毒蛾3龄幼虫体重累计增长率降低。LdNPV胁迫导致不同CO₂含量（397、550和750 μL/L）条件下饲养的舞毒蛾3龄幼虫体重累计增长率分别比对照组增加81.27%、71.63%和68.41%；随着CO₂含量升高幼虫感染LdNPV死亡率增加，750 μL/L高含量处理组死亡率为27.09%。高CO₂含量胁迫下舞毒蛾3龄幼虫体内解毒酶CarE和AChE活性随着CO₂含量升高而诱导增加，ALP活性随CO₂含量增加抑制下降；保护酶CAT活性随着CO₂含量升高诱导增加，而SOD活性随着CO₂含量升高抑制减少。高CO₂含量条件下生长的舞毒蛾3龄幼虫接种LdNPV后，随着CO₂含量升高体内CarE、ALP、AChE和CAT活性被抑制，而SOD活性表现为诱导增加。结论不同CO₂含量下舞毒蛾饲养至3龄幼虫接种LdNPV，随着CO₂含量增加，幼虫体重累计增长率减少、死亡率增加。舞毒蛾幼虫CarE、AChE、ALP和CAT活性随着LdNPV处理时间和CO₂含量增加而主要表现为抑制减少；SOD活性则主要表现为诱导增加。CO₂含量升高可能通过影响生长发育和生理生化增加LdNPV对舞毒蛾幼虫的致病力。 

Effects of LdNPV on growth,development and biochemical enzymatic activities of Lymantria dispar under CO_2 concentration stress

ObjectiveIn this study, the forest pest Lymantria dispar was used to study the effects of LdNPV on the development, detoxifying enzymes and protective enzymes of Lymantria dispar larvae under CO₂ concentration stress.MethodThe effects of LdNPV on the growth and development of L. dispar larvae under different CO₂ concentrations (397, 550 and 750 μL/L) reared into the closed CO₂ artificial climate chamber, and in vivo detoxifying enzymes and protective enzyme activities of L. dispar larvae were also determined by spectrophotometry.Result The cumulative growth rate of fresh mass of the 3rd instar larvae of L. dispar decreased under high CO₂ concentration stress. The cumulative increase rates of fresh mass of the 3rd instar L. dispar larvae infected by LdNPV were higher than the control by 81.27%, 71.63% and 68.41%, respectively. The mortality rate increased with increasing CO₂ concentration, and the cumulative mortality rate of 750 μL/L CO₂ treatment was 27.09%. Under the high CO₂ concentration stress, the activities of detoxifying enzymes CarE and AChE in the 3rd instar larvae of L. dispar were induced with the increase of CO₂ concentration, and the ALP activity was inhibited with the increase of CO₂ concentration; the activity of protective enzyme CAT was induced with the increase of CO₂ concentration while SOD activity was inhibited with increasing CO₂ concentration. However, the activities of CarE, ALP, AChE and CAT in 3rd instar larvae of L. dispar infected by LdNPV were inhibited with the increase of CO₂ concentration, and the activity of SOD was induced with the increase of CO₂ concentration.ConclusionThe duration and cumulative mortality rate of L. dispar larvae infected by LdNPV increased while cumulative growth rate decreased after different CO₂ concentraion treatments. The activities of CarE, AChE, ALP and CAT in 3rd instar larvae of L. dispar decreased with the increase of both the treatment time and CO₂ concentration, and the activities of SOD were increased. Therefore, elevated concentration of CO₂ may increase the virulence of LdNPV to the L. dispar larvae by affecting the growth, development and biochemical enzymes.