黄绿绿僵菌侵染对褐飞虱部分生理生化指标的影响

本研究测定了3个不同浓度（1.0×10⁷、1.0×10⁸和1.0×10⁹孢子/mL）黄绿绿僵菌孢悬液处理的褐飞虱Nilaparvata lugens Stå；l体内的羧酸酯酶（carboxylesterase，CarE）、谷胱甘肽-S-转移酶（glutathione-S-transferase，GST）、超氧化物歧化酶（superoxide dismutase，SOD）、过氧化氢酶（catalase，CAT）、过氧化物酶，酚氧化酶（phenoloxidase，PO）以及尿酸与6种必需氨基酸含量随侵染时间的变化。结果表明，3个浓度绿僵菌溶液处理的褐飞虱种群体内CarE与GST含量在处理72 h后均呈现显著下调趋势；而CAT与SOD含量随着处理时间延长，呈现上升趋势，其中SOD 3个浓度处理至72 h时分别达到430.87、377.64和376.16 U/mg显著高于对照的276.63 U/mg；酚氧化酶PO含量在24和48 h内均无显著变化，直至72 h，1.0×10⁹孢子/mL浓度处理褐飞虱种群体内PO含量上升至316.43 U/mg。结果显示，虽然低浓度处理褐飞虱种群体内产生大量尿酸的囤积，但同一处理褐飞虱种群体内的6种必需氨基酸含量未呈现显著降低趋势，当处理72 h后，1.0×10⁷孢子/mL处理褐飞虱种群体内赖氨酸（Lys）与苏氨酸（Thr）含量反而突然上升至204.68和112.38 μg/g。结果显示绿僵菌的侵染会对褐飞虱体内解毒酶、保护酶以及氨基酸含量等造成影响。

Physiological Effects of Metarhizium flavoviride on Brown Planthopper (Nilaparvata lugens Stål)

In the present study, the effects of infection by Metarhizium flavoviride on contents of carboxylesterase (CarE), glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), peroxidase (PO), uric acid and 6 essential amino acids in the brown planthopper Nilaparvata lugens Stål were investigated. Three concentrations (1.0×10⁷, 1.0×10⁸ and 1.0×10⁹ spores/L) of M. flavoviride solution were treated by spraying to the planthopper. The results showed that the contents of CarE and GST in the M. flavoviride-treated N. lugnes were significantly lower than those in the untreated N. lugens at 72 h after spraying. CAT and SOD contents in N. lugens increased over time after M. flavoviride spraying. The contents of SOD in the M. flavoviride-treated N. lugnes were 430.87 U/mg, 377.64 U/mg and 376.16 U/mg for the three spraying concentrations, respectively, at 72 h after treatment, which were significantly higher than those in the untreated N. lugens. The contents of PO were not significantly different among treatments at 24 h and 48 h after treatment. However, at 72 h after spraying with 1.0×10⁹ spores/L M. flavoviride, the contents of PO in the M. flavoviride-treated N. lugnes increased to 316.43 U/mg, significantly higher than those in the control N. lugnes. The results also indicated spraying with 1.0×10⁷ spores/L M. flavoviride significantly increased the accumulation of uric acid. The amino acids showed no significant decrease in the M. flavoviride-treated N. lugens. But the levels of lysine (Lys) and threonine (Thr) were as high as 204.68 μg/g and 112.38 μg/g, respectively, at 72 h after spraying with 1.0×10⁷ spores/L M. flavoviride, significantly higher than those in the control N. lugens. In summary, the infection of M. flavoviride affects the detoxification enzymes, protective enzymes and the content of amino acids in N. lugens.