舞毒蛾(Lymantria dispar)酚氧化酶的酶学特征及有机溶剂对其活性的影响

经35%饱和度硫酸铵分级沉淀,将舞毒蛾(Lymantria dispar)酚氧化酶部分纯化。测定该酶最适pH值为6.5,pH在6.5～7.5范围内酶保持稳定的活力。最适温度为35℃,当温度低于25℃时,酶具有稳定的活力。以L-多巴、邻苯二酚和焦性没食子酸为底物时,测定酚氧化酶对底物的专一性,结果表明其Km值分别为3.19、10.74和19.26 mmol.L-1。本实验还研究了有机溶剂对酶活力的影响,结果表明甲醇、乙醇、丙酮和二甲苯对舞毒蛾酚氧化酶都有持续的抑制作用,其IC50分别为0.450、.430、.41和0.13 mmol.L-1。

Control of Lymantria dispar L. by biological agents

The experiment on control of Lymantria dispar L by using different kinds ofbiological measures, including nuclear polyhedrosis virus (NPV) of Lymantria dispar L., BtMP-342,sex-attractant as well as botanical insecticide, was carried out in the forest regions of InnerMongolia in 2003. Two concentrations (2.632x10^6 PIB ? ml^(-1) and 2.632x10^7 PIB ?ml^(-1)) of Lymantria dispar L. NPV were sprayed on the 2rd-instar-larvae of L. dispar and 70% and77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instarlarvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific ForestryResearch Center also showed a good result in trapping L. dispar adults. The self-produced botanicalinsecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains,China, exhibited a good control result in controlling the larvae of L. dispar, and 82% mortalitywas observed when spraying primary liquid of the botanical insecticide on the 3rd-5th-instar-larvaein lab.

Influences of the Populus deltoids seedlings treated with exogenous methyl jasmonate on the growth and development of Lymantria dispar larvae

Lyantria dispar larvae were fed with the leaves of Populus deltoids seedlings exposed to methyl jasmonate （MeJA） for 24 h. The growth and development of the larvae were investigated, and phenolics contents in treated leaves including pyrocatechol, caffeic acid, coumarin, fernlic acid and benzoic acid were also surveyed by high-pressure liquid chromatography （HPLC）. Results indicated that approximate digestibility, efficiency of conversion of ingested food, efficiency of conversion of digested food, and weight of the larvae were inhibited obviously, especially from the sixth day, which may result from the increase of total phenolics contents in treated leaves. This result provides strong supports for MeJA acting as the airborne signal molecule between woody plants.

Molecular characterization and functional analysis of USP-1 by RNA interference in the Asian gypsy moth Lymantria dispar

Ecdysteroids play an important role in regulating diverse physiological processes in arthropods,such as molting,metamorphosis,reproduction and diapause.Ecdysteroids mediate the response by binding to a heterodimeric complex of two nuclear receptors:the ecdysone receptor and the ultraspiracle(USP).To investigate the role of USP in development of the Asian gypsy moth(Lymantria dispar),a USP cDNA was obtained from the transcriptome of L.dispar and verified by PCR.In-depth profiling of transcript levels of L.dispar USP-1(LdUSP-1)at different developmental stages and over time in thirdinstar larvae and different tissues isolated during the thirdinstar stage of L.dispar was then carried out.Transcript levels of LdUSP-1 were relatively high before 72 h in the third-instar larvae after ecdysis and in the adult male.The function of LdUSP-1 in molting was analyzed by knockdown of LdUSP-1 in third instar larvae using RNA interference.Silencing of LdUSP-1 significantly downregulated the transcript level of E75,an ecdysone-inducible gene,and of Sad,a Halloween gene.In addition,the duration of the third-instar stage was slightly shortened and larval mortality increased after the LdUSP-1 knockdown.

Molecular cloning, characterization, and antioxidant function of catalase in Lymantria dispar asiatic (Lepidoptera: Lymantriidae) under avermectin stress

The critical antioxidant catalase(CAT)breaks down hydrogen peroxide induced by environmental stresses.Here we cloned full length catalase cDNA from Lymantria dispar asiatic(LdCAT).Bioinformatic analyses showed that open reading frames of LdCAT contains 1524 bp,encoding 507 amino acids with molecular weight of 126.99 kDa,theoretical pI of 5.00,aliphatic index of 29.92,grand average of hydropathicity of 0.764,and instability index(II)of 46.56.Protein BLAST and multiple sequence alignment indicated that LdCAT had high identity with CAT from other insects,especially lepidopterans.In a phylogenetic analysis,LdCAT was most similar to CAT from Spodoptera litura and S.exigua.Quantitative realtime polymerase chain reaction showed that LdCAT transcripts in all instar larvae and the five tissues tested,verifying the ubiquity of LdCAT in L.disapr.Moreover,LdCAT of third instar larvae was significantly upregulated after they fed on avermectin at sublethal and LC10 doses.The highest relative transcript levels were found 2 h after an avermectin spray at LC90,and in the cuticula,rather than heads,fat bodies,malpighian tubes,and midguts after a spray avermectin at a sublethal concentration.The expression level of LdCAT under pesticide stresses here suggested that CAT is an important antioxidant enzyme of L.disapr defensing against pesticide stress and may be a good target for controlling this pest.

Life circle and bionomics of Lymantria dispar L.

The life circle and bionomics ofLymantria dispar was studied from the May to the July of 1997 in Tulihe Forestry Enterprise of Inner Mongolia. The results showed thatL. dispar has one generation in a year, larvae overwinters in eggs, and last 50 days to grow up. From the completing of larvae period to the appearing of adults lasts 11 days. The study made a basis for the period forecasting of L.dispar in Inner Mongolia.

The sex peptide receptor in the Asian gypsy moth,Lymantria dispar,is involved in development and stress resistance

The G protein-coupled receptor(GPCR)regulates downstream genes by binding to a heterotrimeric G protein.However,the function of sex peptide receptor(SPR)in lepidopteran species is mostly unknown.Understanding the physiological functions of SPR in insects is essential for exploring new insecticidal targets.In the present study,the functions of an SPR in Lymantria dispar(Asian gypsy moth;LdSPR)were investigated.The expression of LdSPR was the highest in the 6 th instar larval stage,and there was a large difference in expression between male and female adults.After LdSPR gene silencing,L.dispar larvae showed increased sensitivity to high temperature,starvation,and oxidative stress,indicating that LdSPR enhances stress resistance.These results enrich our knowledge of the function of the insect SPRs,which will lead to a better understanding of other insect GPCR family members and the identification of new targets for the development of environmentally friendly pesticides.

Synergic effect of sex pheromone(7R,8S)-cis-7,8-epoxy-2-methyloctadec-17-ene on(+)-disparlure of the Asian gypsy moth,Lymantria dispar, in Korea

field attraction test of (7R,8S)-cis-7,8-epoxy-2- methyloctadec-17-ene (= 7R,8S-epo-2me-17ene-18Hy), a trace component of the sex pheromone gland of the Asian gypsy moth,(Lymantria dispar), traps that were baited with the trace component attracted more L. dispar than traps baited with (7S,8R)-cis-7,8-epoxy-2-methyloctadec-17-ene (= 7S,8R-epo-2me-17ene-18Hy) and unbaited traps. However, traps baited with 7R,8S-epo-2me-17ene-18Hy were less attractive than traps baited with (+)-disparlure [=(7R,8S)-cis-7,8-epoxy-2-methyloctadecane], the sex pheromone of L. dispar. Combination tests with (?)-disparlure, 7R,8S-epo-2me-17ene-18Hy, and 7S,8R-epo-2me- 17ene-18Hy revealed that 7R,8S-epo-2me-17ene-18Hy acted synergistically with (?)-disparlure.

Molecular systematics analysis of Lymantria dispar based on 18S rRNA and cox1 mtDNA sequence data

The complete sequence of the 18S ribosomal RNA gene （18S rRNA） from Lymantria dispar was cloned and analysed here. 18S rRNA and mitochondrial cytochrome c oxidasel （coxl） gene sequences of Lymantria dispar were compared with homologous sequences of other nine insects from different orders. Analytic results showed that 18S rRNA of these insects had two conserved domains and the second domain was an even more conserved region. The phylogenetic trees based on the full-length sequence and the second domain fragment of 18S rRNA as well as sequence of coxl from different orders indicated that Lepidoptera and Trichoptera, which belongs to Amphiesmenoptera, had a closer phylogenetic relationship and fewer differences were observed comparing with traditional taxonomic results.

The effect analysis of the diapause duration on the hatching parameters of the artificial semi-annual population of Lymantria dispar caterpillars

The paper investigates the existence of a relationship between the diapause duration and the temperature threshold of hatching,the variances in temperature and hatching time of the artificial six-month population of Lymantria dispar caterpillars.A half-year population gives two generations a year under artificial conditions.A comparative analysis of these parameters with similar parameters of the hybrid population of L.dispar,as well as studies by other authors,has been carried out.The Eigen quasispecies model was used for the mathematical formalization of the evolution process.The results of this work can be used to study the evolution of L.dispar.

Estimate of parameters changing of the Lymantria dispar artificial population in different environmental conditions using the quasispecies model

This paper gives an interpretation of the quasispecies concept for an experiment of growing the Lymantria dispar artificial population.The changes estimate in the population parameters for a significant change in environmental conditions at the stage of hatching caterpillars from the eggs was given.Three numerical and two random parameters were used for quantitative analysis.They characterize the development of individuals of the population at this stage.The parameter changes significance was verified with using statistical tests.The results obtained do not contradict the quasispecies model.The use of fuzzy sets describes the transition from one quasispecies to another at a significant change in environmental conditions.

Insights into the Temporal Gene Expression Pattern in Lymantria dispar Larvae During the Baculovirus Induced Hyperactive Stage

Baculoviruses are effective biological control agents for many insect pests. They not only efficiently challenge the host immune system but also make them hyperactive for better virus dispersal. Some investigations have focused on the viral mechanisms for induction of such altered response from the host. However, there are no current studies monitoring changes in gene expression during this altered phenotype in infected larvae. The L. dispar multiple nucleopolyhedrovirus(Ld MNPV) induces hyperactivity in third instar L. dispar larvae at 3-days post infection(dpi), to continued till 6 dpi. The transcriptome profiles of the infected and uninfected larvae at these time points were analyzed to provide new clues on the response of the larvae towards infection during hyperactivity. Gene ontology enrichment analysis revealed, most of the differentially expressed genes(DEGs) were involved in proteolysis, extracellular region, and serine-type endopeptidase activity. Similarly, Kyoto Encyclopedia of Genes and Genome enrichment analysis showed maximum enrichment of 487 genes of the signal transduction category and neuroactive ligand–receptor interaction sub-category with 85 annotated genes. In addition, enrichment map visualization of gene set enrichment analysis showed the coordinated response of neuroactive ligand–receptor interaction genes with other functional gene sets, as an important signal transduction mechanism during the hyperactive stage. Interestingly all the DEGs in neuroactive ligand–receptor interactions were serine proteases, their differential expression during the hyperactive stage correlated with their conceivable involvement in disease progression and the resulting altered phenotype during this period. The outcome provides a basic understanding of L. dispar larval responses to Ld MNPV infection during the hyperactive stage and helps to determine the important host factors involved in this process.

两种丛枝菌根真菌定殖青山杨后对舞毒蛾的抗性研究

【目的】研究丛枝菌根真菌(AMF)对青山杨抗虫性的影响以及舞毒蛾对AMF定殖青山杨的适应能力,为AMF定殖青山杨后抗虫性的研究提供科学依据。【方法】分别以对照(CK,无AMF定殖)、根内根孢囊霉(GI)或摩西管柄囊霉(GM)定殖的青山杨叶片饲喂舞毒蛾幼虫,统计3、4、5龄幼虫的体重、体长、头壳宽和食物利用率,测定4、5龄幼虫解毒酶酸性磷酸酯酶(ACP)和碱性磷酸酯酶(AKP)的活性。【结果】GI组3、4龄幼虫的体重显著高于对照组(P<0.05),5龄与对照组差异不显著,GM组5龄幼虫的体长、体重、头壳宽、食物利用率均显著高于对照组。GI组3龄幼虫取食量显著高于对照组(P<0.05),4、5龄显著低于对照组,GM组5龄显著高于对照组,3、4龄与对照组差异不显著。GI组ACP显著低于对照组(P<0.05),AKP在4龄显著高于对照组,5龄AKP活性显著低于对照组。GM组两种解毒酶活性均显著高于对照组。【结论】GI定殖的青山杨能促进舞毒蛾低龄幼虫的生长,对舞毒蛾老熟幼虫的生长影响不显著。GM定殖青山杨叶片促进了舞毒蛾幼虫的生长发育,提高了食物的利用效率,激发了幼虫体内磷酸酯酶活性,表明舞毒蛾对GM定植的青山杨有更好的适应性。AMF对树木及植食性昆虫的影响具有种类特异性,GI定殖对青山杨的抗虫性的影响呈中性,GM定殖对青山杨的抗舞毒蛾产生负效应。

舞毒蛾谷胱甘肽S-转移酶对杨树次生物质协同溴氰虫酰胺的胁迫响应

为了明确舞毒蛾Lymantria dispar谷胱甘肽S-转移酶(GST)对杨树次生物质协同溴氰虫酰胺的胁迫响应机制,选择3种杨树次生物质(黄酮、槲皮素、芦丁)以及新型邻二苯甲酰胺类杀虫剂溴氰虫酰胺作为胁迫外源化合物,以舞毒蛾2龄幼虫为研究对象,通过人工饲料添加次生物质和溴氰虫酰胺的单剂和混剂,测定对舞毒蛾存活率、谷胱甘肽S-转移酶活性及其基因表达影响。结果表明,处理48 h后,3种联合处理组舞毒蛾幼虫的存活率显著低于对照组和各杨树次生物质单剂处理组,存活率依次为53.33%、60.00%和53.33%,各联合处理组幼虫存活率与溴氰虫酰胺处理组差异不显著。除处理6 h外,不同杨树次生物质单剂处理后GST活性均诱导增加。溴氰虫酰胺处理组在48 h内GST活性显著高于单剂处理组和对照组。除联合处理1在6 h、12 h的GST诱导活性低于溴氰虫酰胺处理组外,各联合处理组的GST诱导活性均高于溴氰虫酰胺处理组。舞毒蛾2龄幼虫取食含有不同处理的人工饲料后,其体内LdGSTe2、LdGSTs1、LdGSTs2和LdGSTz1均有所表达,且不同处理的诱导程度呈现差异。以上研究结果为杨树次生物质协同溴氰虫酰胺防控舞毒蛾提供理论依据,同时为生产实践中杀虫剂的合理使用提供参考。

α−三联噻吩对舞毒蛾幼虫的杀虫活性和生理生化影响

为探究α−三联噻吩(α−terthienyl,α−T)对舞毒蛾Lymantria dispar 3龄幼虫的杀虫活性和生理生化影响,利用饲料混药法、分光光度法和HE染色法,分别测定α−T处理对舞毒蛾3龄幼虫的毒力及对幼虫生长发育、营养物质含量、抗氧化酶活性、中肠组织的影响。结果表明:α−T对舞毒蛾3龄幼虫处理72 h有良好的毒杀活性,亚致死浓度(LC20)和致死中浓度(LC_(50))分别为20.37,178.13μg/mL;LC20和LC_(50)的α−T处理舞毒蛾3龄幼虫72 h能够显著降低其体质量增长量,降低体内可溶性蛋白、碳水化合物、海藻糖、脂质的含量;LC_(50)的α−T对舞毒蛾幼虫中肠过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性具有显著的抑制作用,能够损伤幼虫中肠组织,产生显著的病理变化。α−T能够通过降低舞毒蛾幼虫营养物质含量、抑制抗氧化酶活性、损伤中肠组织,从而抑制舞毒蛾幼虫的生长发育,产生毒性。

舞毒蛾研究进展

舞毒蛾是农林业上的重要害虫,具有食性杂、危害重、分布广、幼虫随风移动等特点。该文综述了近年来舞毒蛾在国内外的研究进展,对舞毒蛾在形态特征、分布及危害、防治措施、外界胁迫、寄主病毒等方面进行归纳总结,以期为同领域深入研究提供参考。

包头地区舞毒蛾的防治措施

舞毒蛾是包头地区的主要常发性林业有害生物,做好舞毒蛾的防控工作对保护包头市森林资源,改善生态环境,维护生态系统的多样性、稳定性、持续性,推动绿色发展,促进人与自然和谐共生,具有十分重要的意义。

4种寄主植物对舞毒蛾幼虫生长发育的影响

研究了4种寄主植物对舞毒蛾生长发育的影响,结果表明:①舞毒蛾1龄幼虫在山东地区4、5月份对西府海棠、黄栌及垂柳危害严重,对华山松几乎无危害;②舞毒蛾幼虫在上述3种危害严重的寄主植物上均可完成发育,1~3龄时西府海棠为最佳寄主植物,4~6龄垂柳为最佳寄主植物;③寄主植物影响了舞毒蛾幼虫的生长发育历期、体重及头宽,不同寄主植物饲喂下,同龄期体重较小的幼虫头宽也较小;④舞毒蛾幼虫各龄期头宽在组内和组间均重叠较小,同时发生时可用于分龄;而体重重叠区域较大,不适于分龄。