Time-dependent stress evidence in dynamic allocation of physiological metabolism of Nilaparvata lugens in response to elevated CO2.

To assess the time-dependent stress evidence in dynamic allocation of physiological metabolism of Nilaparvata lugens nymphs in response to elevated CO2, we measured the time-dependent allocation of nutrient compositions and physiological metabolism in the bodies of N. lugens at 1h, 4h and 12h under elevated CO2. Elevated CO2 significantly increased the contents of nutrient compositions (protein, glucose and total amino acids) and catalase (CAT) enzyme activity in the body of N. lugens at 12h relative to 1h and 4h (P < 0.05). Significantly higher genes expression levels of acetylcholinesterase (AChE), heat shock protein (HSP70) and vitellogenin gene (vg) were observed in the body of N. lugens compared with those in ambient CO2 at 4h (P < 0.05). These results showed that there was an instantaneous reaction of N. lugens nymphs to elevated CO2, which indicated N. lugens may enhance stress defense response to future increasing CO2 levels.