Dynamics and diversity of symbiotic bacteria in Apolygus lucorum at different developmental stages

Background Apolygus lucorum is a worldwide omnivorous pest damaging a range of crops and causing great economic losses.Symbiotic bacteria living in insects play a key role in the nutrition,physiology,and behavior of hosts.Here,we present an experiment using Illumina HiSeq sequencing targeting the V3–V4 regions of bacteria’s 16S rRNA throughout the entire life cycle of A.lucorum.Results The first and second instar nymphs have the largest alpha diversity compared with other life stages of the insect.Bacterial phyla Proteobacteria(72.29%),Firmicutes(15.24%),Actinobacteria(7.76%)exhibit the largest relative abundance in all developmental stages.Erwinia(23.97%)and Lactococcus(10.62%)are the two genera with the high-est relative abundance.The relative abundance of Erwinia in the nymph stage is significantly greater than the adult stage,and the relative abundance of Lactococcus in 6-day-old and 9-day-old adult females is higher compared with adult males.Conclusions These results reveal that microbial community composition and relative abundance shift dynamically at different life stages,implying that different bacterial phyla and genera may have specific roles in specific life stages such as metabolism,nutrition absorption,detoxification,and reproduction.This study reveals for the first time the community composition and ecological dynamics of symbiotic bacteria throughout the life stages of A.lucorum,and thus may provide insight to new strategies for pest control.

Biosynthesis of artemisinic acid in engineered Saccharomyces cerevisiae and its attractiveness to the mirid bug Apolygus lucorum

Artemisia annua is an important preferred host of the mirid bug Apolygus lucorum in autumn.Volatiles emitted from A.annua attract A.Iucorum.Volatile artemisinic acid of A.annua is a precursor of artemisinin that has been widely investigated in the Chinese herbal medicine field.However,little is known at this point about the biological roles of artemisinic acid in regulating the behavioral trends of A.lucorum.In this study,we collected volatiles from A.annua at the seedling stage by using headspace solid phase microextraction(HS-SPME).Gas chromatography-mass spectrometry(GC-MS) analysis showed that approximately 11.03±6.00 and 238.25±121.67 ng hartemisinic acid were detected in volatile samples and milled samples,respectively.Subsequently,a key gene for artemisinic acid synthesis,the cytochrome P450 gene cyp71 av1,was expressed in engineered Saccharomyces cerevisiae to catalyze the production of artemisinic acid.After the addition of exogenous artemisinic alcohol or artemisinic aldehyde,artemisinic acid was identified as the product of the expressed gene.In electroantennogram(EAG) recordings,3-day-old adult A.lucorum showed significant electrophysiological responses to artemisinic alcohol,artemisinic aldehyde and artemisinic acid.Furthermore,3-day-old female bugs were significantly attracted by artemisinic acid and artemisinic alcohol at a concentration of 10 mmol L,whereas 3-day-old male bugs were attracted significantly by 10 mmol Lartemisinic acid and artemisinic aldehyde.We propose that artemisinic acid and its precursors could be used as potential attractant components for the design of novel integrated pest management strategies to control A.lucorum.

Suppression Subtractive Hybridization Reveals Different Responses of Two Varieties of Gossypium arboreum L. Under Apolygus lucorum Stress

Plants reshape their transcriptomes, proteomes and metabolomes in response to insect damage. In this study, we used suppression subtractive hybridization to investigate the transcriptomes of two cotton varieties （CCRI41 and CCRI23） under Apolygus lucorum damage. From the CCRI23 libraries we obtained 92 transcripts and from the CCRI41 libraries we obtained 96 transcripts. 26 and 63 of the transcripts from CCRI23 and CCRI41, respectively, had known functions. Using reverse transcription PCR, we detected expression proifle of genes with known functions. Ultimately, we identiifed eight signiifcantly regulated genes, including one downregulated and four upregulated genes from the CCRI41 libraries, and one downregulated and two upregulated genes from the CCRI23 libraries. Only the gene encoding the polyphenol oxidase （PPO） is involved in plant defense against insect herbivores, and the others are related to improving tolerance to insect damage. Quantitative real-time PCR was used to study changes in expression levels during A. lucorum damage in CCRI23 and CCRI41. Signiifcantly regulated genes from CCRI23 showed a response in CCRI23 but not response in CCRI41. Similarly, signiifcantly regulated genes from CCRI41 showed a response in CCRI41 but not response in CCRI23. The results showed that, among transcriptomes of cotton varieties, there are different responses to A. lucorum damage.

Occurrence and Pollution-free Control of Apolygus lucorum in Winter Jujube

In recent years, Apolygus htcorum has become the main pest of winter jujube. It sucks juice of young parts of winter jujube and causes falling of buds and flowers, leaf perforations, deformities and fall- off of fruits, leading to serious economic loss. Considering the occurrence characteristics and control problems, the distribution, occurrence regularity, damage characteristics and outbreak reasons of A. lucorum are overviewed and analyzed in this paper, and the pollution-free control measures are also put forward.

Gene cloning,protein expression,and enzymatic characterization of a double-stranded RNA degrading enzyme in Apolygus lucorum

RNA interference(RNAi)is a powerful tool that post-transcriptionally silences target genes in eukaryotic cells.However,silencing efficacy varies greatly among different insect species.Recently,we met with little success when attempting to knock down genes in the mirid bug Apolygus lucorum via dsRNA injection.The disappearance of double-stranded RNA(dsRNA)could be a potential factor that restricts RNAi efficiency.Here,we found that dsRNA can be degraded in midgut fluids,and a dsRNase of A.lucorum(AldsRNase)was identified and characterized.Sequence alignment indicated that its 6 key amino acid residues and the Mg2+-binding site were similar to those of other insects’dsRNases.The signal peptide and endonuclease non-specific domain shared high sequence identity with the brown-winged green stinkbug Plautia stali dsRNase.AldsRNase showed high salivary gland and midgut expression and was continuously expressed through the whole life cycle,with peaks at the 4th instar ecdysis in the whole body.The purified AldsRNase protein obtained by heterologously expressed can rapidly degrade dsRNA.When comparing the substrate specificity of AldsRNase,3 specific substrates(dsRNA,small interfering RNA,and dsDNA)were all degraded,and the most efficient degradation is dsRNA.Subsequently,immunofluorescence revealed that AldsRNase was expressed in the cytoplasm of midgut cells.Through cloning and functional study of AldsRNase,the enzyme activity and substrate specificity of the recombinant protein,as well as the subcellular localization of nuclease,the reason for the disappearance of dsRNA was explained,which was useful in improving RNAi efficiency in A.lucorum and related species.

5种杀虫剂对绿盲蝽的室内毒力及田间防效

筛选出防治绿盲蝽(Apolyguslucorum)高效、低毒和安全的杀虫剂,为绿盲蝽的科学防控提供基础数据和科学依据。本研究以食料浸渍法和田间喷雾法,分别测定了噻虫嗪、阿维菌素、苦参碱、鱼藤酮和蛇床子素,5种杀虫剂对绿盲蝽的室内毒力及田间防治效果。室内毒力测定结果显示:5种杀虫剂对绿盲蝽的毒力均随杀虫剂浓度的升高而增强,对绿盲蝽的毒力大小顺序为:噻虫嗪>阿维菌素>苦参碱>鱼藤酮>蛇床子素,田间防治试验结果表明:在绿豆田用药3d后,300mg/L噻虫嗪和600mg/L噻虫嗪的防治效果最好,田间防效均已达到75%以上。在绿豆田用药7d后,600mg/L噻虫嗪的防治效果最好,其次为300 mg/L噻虫嗪和1000 mg/L阿维菌素,田间防效均超过70%,1600 mg/L苦参碱田间防治效果为58.94%,1600 mg/L鱼藤酮和1600 mg/L蛇床子素田间防效约为50%。5种杀虫剂对绿盲蝽均有防治效果,噻虫嗪和阿维菌素对绿盲蝽防治效果较好,建议用于绿盲蝽大田防治。

绿盲蝽气味结合蛋白AlucOBP31配体筛选及EAG测定

绿盲蝽Apolyguslucorum是重要的农业害虫,了解其化学感受机制对该虫的绿色防控具有重要指导意义。气味结合蛋白(Odorant-binding proteins,OBPs)在昆虫化学感受过程中发挥关键作用。为深入探究绿盲蝽OBP家族成员AlucOBP31的生物学功能,本研究采用荧光竞争结合试验和触角电位技术(Electroantennogram,EAG),系统分析了AlucOBP31对候选配体化合物的结合特性及其电生理活性。荧光竞争结合试验结果表明,重组Aluc OBP31蛋白能够与16种配体化合物发生不同程度的结合,其中与植物挥发物β-紫罗兰酮的结合能力最强,而与十二醛和顺-丁酸-3-己烯酯的结合能力相对较弱。值得注意的,AlucOBP31能与绿盲蝽性信息素组分4-氧代-反-2-己烯醛结合,提示其可能参与绿盲蝽的性信息素识别过程。此外,AlucOBP31还对槲皮素、芦丁水合物、棉酚和单宁酸等4种非挥发性苦味物质具有强结合能力,暗示其可能在绿盲蝽的味觉识别中发挥一定作用。EAG试验进一步验证了AlucOBP31配体的电生理活性。绿盲蝽雌、雄成虫的触角对12种AlucOBP31挥发性配体均产生了明显的EAG反应,其中对顺-丁酸-3-己烯酯和4-氧代-反-2-己烯醛的EAG响应值显著高于其它配体,并且雄性触角对这些配体的EAG反应普遍强于雌性,提示AlucOBP31介导的化学感受过程可能存在性别差异。综上所述,本研究系统分析了绿盲蝽AlucOBP31的结合特性及相应配体的电生理活性,发现该蛋白能够结合寄主植物挥发物、绿盲蝽性信息素组分以及多种非挥发性苦味物质,表明AlucOBP31可能在绿盲蝽的嗅觉和味觉识别过程中发挥多重生物学功能。这一发现为进一步探究AlucOBP31与其配体在绿盲蝽寄主选择、交配等重要生命活动中的生物学意义提供了研究基础,加深了我们对绿盲蝽化学感受机制的认知,也为绿盲蝽的绿色防控提供了新的分子靶标。

金龟子绿僵菌CQMa421对棉蚜、绿盲蝽的田间防效

棉花是我国重要的经济作物,虫害严重制约了棉花生产,造成棉农的经济损失。目前,化学杀虫剂仍是防治棉花虫害的主要手段,长期使用化学杀虫剂导致棉蚜Aphis gossypii、绿盲蝽Apolygus lucorum产生抗药性,降低防治效果。本研究使用80亿孢子/mL金龟子绿僵菌CQMa421可分散油悬浮剂防治棉蚜、绿盲蝽,室内生测结果表明,金龟子绿僵菌CQMa421能有效侵染棉蚜和绿盲蝽,随着浓度的升高,对棉蚜和绿盲蝽的毒力增强。田间试验结果表明,该药剂能有效控制棉花主要害虫棉蚜和绿盲蝽。采用1200 mL/hm 2用量,药后14 d对棉蚜的防效达94.42%;采用1350 mL/hm 2用量,药后14 d对绿盲蝽的防效分别达到87.25%(新疆),91.62%(湖北)。

新疆南疆绿盲蝽季节性寄主转移规律

为了明确南疆地区绿盲蝽Apolygus lucorum不同季节的寄主植物种类以及在主要寄主作物上的种群发生动态,本研究在2021年采用扫网法对阿克苏地区农田生态系统中常见的23个科55种植物上的绿盲蝽种群动态进行了周年调查,并于2019年-2021年通过黄板诱捕法系统监测了绿盲蝽种群在当地枣园、棉田的发生情况。绿盲蝽在当地1年发生5代,存在明显的寄主转移现象。绿盲蝽1~2代(5月中旬至7月上旬)主要在枣树Ziziphus jujuba上为害,枣树花期结束2代成虫大量迁出枣园,3~4代(7月上旬至9月中旬)主要在棉田为害,5代(9月上旬至10月中旬)迁回枣园。除为害主要作物枣树、陆地棉Gossypium hirsutum外,1代绿盲蝽的寄主植物有甘草Glycyrrhiza uralensis、藜Chenopodium album、欧洲油菜Brassica napus,2~3代的寄主植物有白花草木樨Melilotus albus、黄香草木樨Melilotus officinalis、甘草、藜、欧洲油菜、骆驼刺Alhagi camelorum、萹蓄Polygonum aviculare、苜蓿Medicago sativa等,4~5代的寄主植物包括青蒿Artemisia caruifolia、艾A.argyi、白花草木樨、欧洲油菜、萹蓄等。枣园及棉田绿盲蝽成虫种群消长动态与上述寄主转移规律高度吻合。研究结果为南疆地区果棉生态系统中绿盲蝽的发生测报与科学防治提供重要的科学依据。

A de novo transcriptomic analysis to reveal functional genes in Apolygus lucorum

The widespread planting of genetically engineered cotton producing the CrylAc toxin has led to significantly reduced pesticide applications since 1997. However, conse- quently, the number of green mirid bugs （GMB）, Apolygus lucorum （Meyer-Diir） has in- creased. So far the GMB, instead of the cotton bollworm Helicoverpa armigera （Hiibner）, has become the major pest in the transgenic Bt cotton field and has influenced cotton yield. Disproportionately, only a few studies on GMB at molecular level have been re- ported. Libraries from both third instar nymphs and adults were sequenced using Illumina technology, producing more than 106 million short reads and assembled into 63 029 uni- genes of mean length 597 nt and N50 813 nt, ranging from 300 nt to 9771 nt. BLASTx analysis against Nr, Swissprot, GO and COG was performed to annotate these unigenes. As a result, 26 478 unigenes （42.01%） matched to known proteins and 107 immune-related, 320 digestive-related and 53 metamorphosis-related genes were detected in these annotated unigenes. Additionally, we profiled gene expression using mapping based differentially expressed genes （DEGs） strategy between the two developmental stages： nymph and adult. The results demonstrated that thousands of genes were significantly differentially ex- pressed at different developmental stages. The transcriptome and gene expression data provided comprehensive and global gene resources of GMB. This transcriptome would improve our understanding of the molecular mechanisms of various underlying biological characteristics, including development, digestion and immunity in GMB. Therefore, these findings could help elucidate the intrinsic factors of the GMB resurgence, offering novel pest management targets for future transgenic cotton breeding.

The mitochondrial genome of the plant bug Apolygus lucorum （Hemiptera： Miridae）＂ Presently known as the smallest in Heteroptera

The complete mitochondrial （mt） genome of the plant bug, Apolygus lucorum, an important cotton pest, has been sequenced and annotated in this study. The entire circular genome is 14 768 bp in size and represents the smallest in presently known heteropteran mt genomes. The mt genome is encoding for two ribosomal RNA （rRNA） genes, 22 transfer RNA （tRNA） genes, 13 protein coding genes and a control region, and the order, content, codon usage and base organization show similarity to a great extent to the hypothetical ancestral model. All protein coding genes use standard initiation codons ATN. Conventional stop codons TAA and TAG have been assigned to the most protein coding genes; however, COIII, ND4 and ND5 genes show incomplete terminator signal （T）. All tRNA genes possess the typical clover leaf structure, but the dihydrouridine arm of tRNAser（A6N） only forms a simple loop. Secondary structure models of rRNA genes are generally in accordance with the former models, although some differences exist in certain parts. Three intergenic spacers have never been found in sequenced mt genomes of Heteroptera. The phylogenetic study based on protein coding genes is largely congruent with previous phylogenetic work. Both Bayesian inference and maximum likelihood analyses highly support the sister relationship ofA. lucorum and Lygus lineolaris, and Miridae presents a sister position to Anthocoridae.

Identification of heat shock cognate protein 70 gene （Alhsc70） of Apolygus lucorum and its expression in response to different temperature and pesticide stresses

Heat shock cognate protein 70 （Hsc70） is a very important stress-resistance protein of insects against environmental stresses. We employed fluorescent real-time quan- titative polymerase chain reaction and Western-blot techniques to analyze the transcrip- tional and translational expression profiles of AIHSC70 under extreme temperature （4℃ and 40℃） or 4 pesticide stresses in Apolygus lucorum. The results showed that the expres- sion of AIHSC70 were significantly induced by cyhalothrin or extremely high temperature （40℃） in both transcriptional and translational levels （P 〈 0.05）, while the transcriptional and translational level of AIHSC70 decreased significantly in treatments of chlorpyrifos or extreme cold temperature （4℃） （P 〈 0.05）. Moreover, afterApolygus lucorum treated by imidacloprid or emamectin benzoate, the expression of AIHSC70 was only up-regulated significantly at the transcriptional level （P 〈 0.05）, although obviously up-regulated at the translational level of AIHSC70. Therefore, this study confirmed that the Alhsc70 gene played important roles in response to both temperature and pesticide stresses, especially for cyhalothrin or extremely high temperature （40℃）. In addition, the significant polynomial regression correlations between temperature and the Alhsc70 expression level were shown in all the nymph and adult stages （P 〈 0.01）, indicating temperature was an important factor to affect the relative expression of Alhsc70.

Genetic analysis and molecular detection of resistance to chlorpyrifos mediated by the A216S substitution in acetylcholinesterase-1 in the plant bug Apolygus lucorum

The green plant bug Apolygus lucorum is a major pest of Bacillus thuringiensis cotton in China.Previously,we reported that chlorpyrifos resistance in a laboratory-selected strain of A.lucorum(BZ-R)is associated with the homozygosis of an allele in the ace-1 gene encoding an alanine to serine substitution at position 216 of acetylcholinesterase-1.Here we describe the results of crosses between the resistant BZ-R strain(41-fold to chlorpyrifos)and the unselected susceptible BZ-S strain homozygous for the wild type alanine allele at position 216.Resistance to chlorpyrifos was inherited as a semi-dominant trait mainly controlled by a single autosomal gene and co-segregates strongly but not completely with the serine substitution in ace-1.Synergism bioassays and enzyme assays showed that minor contributions to resistance are also made by enhanced cytochrome P450 and carboxylesterase activities.A survey of 25 field populations from five Chinese provinces showed strong positive correlations between 50%lethal concentration against chlorpyrifos and S216 allele and genotype frequencies,although the most tolerant populations still only show 40%-50%S216 allele frequencies.The results above provide important information for designing effective resistance monitoring and management strategies for A.lucorum in China.

氟啶虫胺腈与3种杀虫剂混配对绿盲蝽Apolygus lucorum(Meyer-Dür)的联合毒力测定

[目的]绿盲蝽是转B.t.基因抗虫棉田中的一种重要害虫,本研究旨在筛选成本低效果好的氟啶虫胺腈混剂。[方法]以北京市上庄种群为研究对象,采用点滴法进行室内毒力测定。[结果]4种杀虫剂对北京上庄地区种群的毒力依次为氟啶虫胺腈>高效氯氟氰菊酯>吡虫啉>毒死蜱;联合毒力测定结果显示:氟啶虫胺腈与高效氯氟氰菊酯、毒死蜱分别按1∶4、1∶8混配增效作用最明显,其共毒系数为125.67与170.71。[结论]上述结果可为合理利用氟啶虫胺腈混剂对绿盲蝽进行田间防治提供参考。

Transcriptome analysis of three cotton pests reveals features of gene expressions in the mesophyll feeder Apolygus lucorum

The green mirid bug Apolygus lucorum is an agricultural pest that is known to cause damage to more than 150 plant species.Here,we report the transcriptomes of A.lucorum at three different developmental stages(the second and fifth instar nymphs and adults).A total of 98,236 unigenes with an average length of l,335 nt was obtained,of which 50,640 were annotated,including those encoding digestive enzymes and cytochrome P450 s.Comparisons with cotton bollworm and cotton aphid transcriptomes revealed distinct features of A.lucorum as a mesophyll feeder.The gene expression dynamics varied during development from young nymphs to adults.The high-quality transcriptome data and the gene expression dynamics reported here provide valuable data for a more comprehensive understanding of the physiology and development of mirid bugs,and for mining targets for their control.

性诱捕器悬挂高度对绿盲蝽、棉铃虫和甜菜夜蛾田间诱集效果的影响

为更好地发挥性诱捕器对棉花主要害虫绿盲蝽Apolygus lucorum、棉铃虫Helicoverpa armigera和甜菜夜蛾Spodoptera exigua的监控及诱杀作用,进一步优化性诱捕器田间设置技术,笔者研究了不同悬挂高度对3种害虫性诱捕器田间诱集效果的影响。结果表明,悬挂高度对3种害虫的诱集效果均存在显著影响,绿盲蝽性诱捕器悬挂高度高于棉株顶尖40 cm时效果最好,与顶尖持平和高于顶尖20 cm的诱集效果略低,三者差异不显著;棉铃虫性诱捕器悬挂高度0~40 cm时诱集效果均较好,诱捕器处于顶尖以下时诱集效果显著降低;甜菜夜蛾性诱捕器悬挂高度在高于顶尖20 cm和40 cm时诱集效果差异不显著,高于顶尖40 cm时诱集效果最好。棉花打顶前,绿盲蝽和棉铃虫性诱捕器随着棉花株高变化可适当减少调整频次,但低于棉花顶尖时应及时调整。

绿盲蝽表皮蛋白基因AlCP17的克隆、多克隆抗体制备及表达谱分析

【目的】本研究旨在通过克隆绿盲蝽Apolygus lucorum表皮蛋白(cuticular protein,CP)基因AlCP17、制备其多克隆抗体和分析其时空表达特性,为AlCP17蛋白功能的研究奠定基础,也为进一步解析绿盲蝽表皮发育过程中的信号通路图谱提供依据。【方法】基于前期转录组数据克隆绿盲蝽AlCP17的cDNA全长序列并进行生物信息学分析;构建AlCP17原核表达载体pCZN1-AlCP17并转化大肠杆菌Escherichia coli进行体外表达,利用纯化后的重组蛋白制备AlCP17蛋白多克隆抗体;qRT-PCR检测AlCP17在绿盲蝽不同发育阶段(1-5龄若虫和成虫)和3龄初期若虫不同组织(头、胸、足、中肠、脂肪体和表皮)中的表达谱。【结果】克隆获得绿盲蝽AlCP17全长cDNA序列(GenBank登录号:OM302231),其开放阅读框长594 bp,编码197个氨基酸,预测蛋白分子量为21.69 kD,理论等电点为6.11。编码的蛋白质具有典型的表皮蛋白结构特征,含有节肢动物表皮蛋白几丁质保守结合域(non-cysCBD),即Chitin_bind_4结构域;氨基酸序列比结果对显示,AlCP17与半翅目(Hemiptera)臭虫科(Cimicidae)温带臭虫Cimex lectularius的CPA2B-like的氨基酸序列一致性最高(76.29%);系统发育进化树显示,CP是一种高度保守的蛋白,与温带臭虫的CPA2B-like和茶翅蝽Halyomorpha halys的CP7-like相似性高。IPTG诱导获得原核表达重组蛋白AlCP17,经纯化后制备的AlCP17多克隆抗体纯化效果较好,可以用于后续实验。AlCP17在绿盲蝽不同发育阶段和3龄初期若虫不同组织中均有表达,在初孵1龄若虫中表达量达到峰值,且在若虫各龄期的末期表达量显著上升;在3龄初期若虫中肠中表达量最高。【结论】克隆了绿盲蝽AlCP17基因cDNA全长序列,AlCP17具有昆虫表皮蛋白的典型特征,AlCP17在绿盲蝽体内的表达具有发育阶段特异性和组织特异性。这些结果为今后研究这一蛋白在绿盲蝽表皮发育过程中的生理功能奠定了基础。

10种中草药提取物对棉铃虫、绿盲蝽触杀活性研究

棉铃虫Helicoverpa armigera和绿盲蝽Apolygus lucorum是两种重要的经济作物害虫。为寻找一种安全高效的防治新手段,本文对10种中草药提取物触杀活性开展了研究。结果表明,在10种中草药提取物中,苦杏仁杀虫活性最高,药后7 d棉铃虫、绿盲蝽校正死亡率分别为65.4%和100%。发现苦杏仁粗提物经不同溶剂萃取后发现,氯仿萃取时析出物对绿盲蝽触杀活性最高,药后7 d校正死亡率可达96.9%。硅胶柱分离结果表明,流分L36-48具有较高的触杀活性,药后7 d校正死亡率为84.7%。本研究评价了10种中草药提取物对棉铃虫和绿盲蝽的触杀活性,并对苦杏仁有效成分开展了初步的分离鉴定,以期为两种害虫高效安全的新型药剂开发提供理论基础。

绿盲蝽取食对茶树营养物质及防御酶活性的影响

为明确绿盲蝽(Apolygus lucorum)取食为害对茶树生理生化的影响,采用酶标仪、紫外分光光度法和高效液相色谱法,测定不同受害程度茶树叶片的防御酶活性、初级营养物质和渗透调节物质含量等。结果表明:茶树叶片中初级营养物质可溶性蛋白含量随着受害程度的加深而持续降低,渗透调节物质脯氨酸含量随受害程度加深而不断升高。健康叶片与受害叶片中保护酶活性差异较大,过氧化物酶(POD)、过氧化氢酶(CAT)和多酚氧化酶(PPO)活性随着受害程度加深而不断升高,其中CAT活性在轻度受害下便迅速升高,POD和PPO活性在重度受害下急剧升高;绿盲蝽取食为害可致茶树叶片中苯丙氨酸解氨酶(PAL)和谷胱甘肽还原酶(GR)活性下降,其中GR活性下降幅度较大,为43.9%~53.9%。健康叶片与受害叶片中水杨酸甲酯和茉莉酸甲酯含量存在显著差异,水杨酸甲酯含量随着受害程度加深而不断降低,下降幅度在50%以上;轻度受害叶片中茉莉酸甲酯含量最低,后随着为害程度加深含量升高。综上表明,脯氨酸、POD、CAT、PPO等物质积极参与茶树应对绿盲蝽取食的防御反应。

绿盲蝽、Q型烟粉虱、赤拟谷盗对云木香气味物质的嗅觉反应及其在防治中的应用

选择17种云木香挥发物测定绿盲蝽对其电生理及行为学反应。结果表明,芳樟醇和5-羟甲基糠醛可引起绿盲蝽强烈的电生理反应,且芳樟醇对绿盲蝽雌、雄虫均具有极显著的驱避作用,选择反应率均低于40%。而5-羟甲基糠醛原液与100倍稀释液均能显著地引诱绿盲蝽,选择反应率分别为51.43%和70.59%。此外,芳樟醇原液对Q型烟粉虱驱避与5-羟甲基糠醛对其的引诱作用同样显著。将这两种化合物组合形成“推-拉”策略后,寄主上绿盲蝽和Q型烟粉虱平均虫量分别为(2.2±0.6)头和(1.9±1.0)头,粘虫板上虫量分别为(7.7±0.7)头和(21.9±1.6)头,与对照组差异显著。5-羟甲基糠醛未对赤拟谷盗表现出引诱作用,但芳樟醇驱避作用显著,选择反应率为25%。表明利用“推-拉”策略防治经济害虫具有良好应用前景。