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1.
昆虫几丁质酶可以降解昆虫体壁和围食膜中的几丁质,在昆虫蜕皮等生命活动中发挥重要功能。作为参与昆虫几丁质降解系统的关键酶,Ⅱ家族几丁质酶(ChtⅡ)是少见的多结构域、性质复杂的几丁质酶。对昆虫中编码ChtⅡ的基因沉默会导致昆虫蜕皮失败及死亡率增加。对ChtⅡ的生化性质及晶体结构分析表明,其在几丁质降解系统中起到了“先锋及攻坚”的作用。因此,ChtⅡ有望成为新的杀虫剂靶标。本文综述了近年来关于ChtⅡ的生理功能、结构特征及其抑制剂的研究成果,可为基于昆虫几丁质酶的新杀虫剂创制提供参考。  相似文献   

2.
海藻糖是昆虫的血糖,为昆虫提供能量;海藻糖酶催化海藻糖分解为葡萄糖,是几丁质生物合成的原料。围食膜(peritrophic membranes,PMs)是昆虫消化道特有结构,对昆虫消化食物、保护肠道表皮细胞具有重要作用;几丁质是PMs的重要组分。海藻糖酶(trehalase,Tre)和几丁质合成酶(chitin synthase,CHS)是几丁质合成途径的第1个和最后1个酶。本研究通过饲喂亚洲玉米螟(Orstrinia furnacalis,Asian corn borer,ACB)膜结合海藻糖酶(OfMT)基因特异的干扰dsRNA,研究RNAi对ACB幼虫中肠CHSBOfCHSB)基因表达及幼虫发育的影响。发现处理48 h后,OfMT基因和OfCHSB基因表达量分别下降了52%和53%,幼虫发育迟缓。通过对处理及对照ACB幼虫中肠石蜡切片进行苏木精-伊红染色(hematoxylin-ethanol,HE染色)和几丁质标记,发现血腔内脂肪体组织减小、中肠围食膜组织中几丁质含量减少。推测OfMT基因有可能成为ACB的生物防治的靶标基因。  相似文献   

3.
低温和几丁质酶处理对棉铃虫围食膜的影响   总被引:11,自引:0,他引:11  
应用扫描电镜观察了经低温处理(5℃,24h)和几丁质酶处理的棉铃虫围食膜的形态变化。结果表明,正常围食膜致密平滑,没有孔或缝。低温处理的围食膜产生了孔和缝,孔径可达150nm,使核多角体病毒能进入中肠细胞。经几丁质酶处理的围食膜也出现孔和缝。处理时间越长,破坏越大。几丁质酶处理围食膜对蛋质含量有一定影响,对粮含量变化的影响则较大。  相似文献   

4.
几丁质脱乙酰基酶是几丁质修饰关键酶,在昆虫几丁质组装过程中发挥重要作用,是潜在的绿色农药靶标。课题组近期研究发现家蚕中肠3个几丁质脱乙酰基酶中,BmCDA7对围食膜几丁质具有最高活性,在进食期高表达,可能参与该时期围食膜形成。本研究通过进一步优化分离纯化条件,建立了金属螯合层析和阴离子交换层析两步分离纯化方法,获得了高纯度的BmCDA7重组蛋白。采用SDS-PAGE结合Calcofluor White M2R显色定性确定了BmCDA7对底物乙二醇几丁质的催化活性。通过测定催化反应过程中释放的乙酸量,确定了BmCDA7的最适反应条件、稳定性及底物选择性。BmCDA7催化反应最适温度为60℃,最适pH为8.0,在温度低于60℃以及中性、偏碱性条件下较为稳定。此外,BmCDA7对乙二醇几丁质、胶体几丁质的酶活力分别为2.9926和0.4270 μmol/(min·μmol),而对高结晶度的α-几丁质和β-几丁质无活力。这些结果丰富了昆虫几丁质脱乙酰基酶的生物化学基础研究。  相似文献   

5.
几丁质酶 (EC 3.2.1.14) 可催化几丁质降解生成几丁寡糖,在几丁质代谢通路中发挥着重要作用,在昆虫、真菌和线虫等有害生物的生长发育过程中不可或缺。以几丁质酶为潜在靶标,有望开发出具有全新作用机制的新型农药品种。近年来,由于噻唑烷酮类化合物被报道具有包括几丁质酶抑制活性的多种农用生物活性,其合成方法受到广泛关注。本文以亚洲玉米螟几丁质酶 (OfCht) 为代表,对几丁质酶结构特点,典型糖类、肽类、虚拟筛选和天然产物源酶抑制剂,以及几丁质酶与抑制剂的结合方式进行了概要性综述,着重针对噻唑烷-4-酮、2-硫代噻唑烷-4-酮和噻唑-2,4-二酮3种噻唑烷酮类化合物的合成方法和农用生物活性研究进行了归纳总结,进而对噻唑烷酮类化合物在几丁质酶抑制活性方面的应用进行展望,以期为基于昆虫几丁质酶独特结构特点进行合理设计和发现新型噻唑烷酮类几丁质酶抑制剂用于未来农业害虫防治提供参考。  相似文献   

6.
围食膜(peritrophic membrane,PM)是昆虫中肠前部分泌产生的,它具有保护中肠上皮细胞、阻止病原物的侵染等功能。由于构成围食膜的几丁质、蛋白质、糖蛋白等成分的装配和特殊取向,围食膜是不连续的,其上有“孔洞”。研究表明,颗粒体病毒增强蛋白、荧光增白剂等生物或化学因子能  相似文献   

7.
亚洲玉米螟Ostrinia furnacalis是为害我国主要农作物玉米的一种重要害虫。昆虫表皮在运动、抵御机械损伤及对抗外界环境压力等方面发挥关键性作用。Tweedle(CPT)家族表皮蛋白在形成昆虫表皮中发挥重要作用,研究CPT有助于开发新一代害虫防治方法。本研究在大肠杆菌系统中以包涵体的形式重组表达了Of CPT1蛋白,使用金属螯合层析进行纯化,复性得到了Of CPT1蛋白,收率为50 mg/L。几丁质结合试验发现,Of CPT1对α-几丁质、β-几丁质、壳聚糖、胶体几丁质和几丁质纳米微晶均有一定的结合能力,其中与几丁质纳米微丝结合能力最强。圆二色光谱结果表明,Of CPT1蛋白与壳聚糖结合后二级结构从以α-螺旋占主导变为以β-折叠占主导。本研究利用原核表达系统获得了亚洲玉米螟重组CPT蛋白并表征了它的部分生物化学性质。  相似文献   

8.
几丁质合成抑制剂在白蚁防治中的研究进展   总被引:3,自引:0,他引:3  
刘炳荣  钟俊鸿 《昆虫天敌》2006,28(4):180-187
昆虫生长调节剂是一类新型的第三代杀虫剂,能阻碍或干扰昆虫正常的生长发育,活性高,残毒小,对环境污染少,大量应用于农、林、卫生害虫防治。其中,应用比较广泛的是几丁质合成抑制剂,能阻碍白蚁新表皮的形成,抑制白蚁的蜕皮而致死。目前,几丁质合成抑制剂如氟铃脲、杀铃脲、除虫脲、氟啶脲等已应用于白蚁群体防治,对白蚁有显著的控制作用,是目前砒剂和灭蚁灵较理想的替代物。  相似文献   

9.
棉铃虫是世界性的重要农业害虫。围食膜作为昆虫抵御病原微生物入侵及有害物质的第一道天然保护性屏障,其上可能存在与Bt抗性相关的受体蛋白。本研究以Bt Cry1Ac抗性和敏感品系的棉铃虫围食膜为对象,采用NuPAGE电泳技术、配体杂交、质谱鉴定和生物信息学分析等技术,测定了围食膜蛋白含量,鉴定了蛋白质的组成及与Bt Cry1Ac毒素的结合能力。结果表明敏感品系围食膜中蛋白含量为22.19%,抗性品系围食膜中蛋白含量为26.99%。抗、感品系棉铃虫围食膜上存在与Cry1Ac毒素结合的6个差异蛋白,推测其中棉铃虫羧酸酯酶蛋白和血影蛋白是2个有意义的抗性相关蛋白,2个新蛋白可能参与Bt抗性。研究证明棉铃虫围食膜上存在Bt结合蛋白且与抗性相关,为进一步明确Bt抗性机制、制定合理的Bt抗性治理策略提供了理论依据。  相似文献   

10.
正几丁质酶是具有生物催化活性、能水解几丁质的一类水解酶,许多微生物可通过胞外诱导产生该酶。几丁质广泛存在于植物病原菌、线虫卵和昆虫的细胞壁中,防治植物土传病害时,在土壤中加入几丁质可以刺激土壤微生物胞外分泌几丁质酶,从而抑制病虫害发生(郑秀丽等,2006;孙建波等,2010)。  相似文献   

11.
Helicoverpa armigera is a serious pest of Cajanus cajan in many parts of world. Rapid development of resistance against number of insecticides and cry toxin-based biocontrol agents has led to search for biocontrol agents with alternative mode of action. The ability of chitinolytic bacteria to degrade vital chitinous structure in insects suggests their potential in insect control. The present investigation was carried out to study insect control potential of a high chitinase producing bacterium, Paenibacillus sp. D1. Biocontrol studies with Helicoverpa larvae showed Paenibacillus sp. D1 and its chitinase to be potent antifeedant that reduced the feeding rate and body weight of the larvae. The decreased body weight was attributed to hydrolysis of the chitinous structures of the larvae. This was evident from decrease in the total chitin content and increased mortality of the larvae fed on the leaves treated with Paenibacillus sp. D1 and chitinase as compared to untreated controls. A combined dose of Paenibacillus sp. D1 or its chitinase with an organophosphate insecticide, acephate, was found to be more lethal than their individual treatments suggesting integrated insect control potential of the bacterium.  相似文献   

12.
Many insects, especially nocturnal insects, exhibit positive phototaxis to artificial lights. Light traps are currently used to monitor and manage insect pest populations, and play a crucial role in physical pest control. Efficient use of light traps to attract target insect pests is an important topic in the application of integrated pest management (IPM). Phototactic responses of insects vary among species, light characteristics and the physiological status of the insects. In addition, light can cause several biological responses, including biochemical, physiological, molecular and fitness changes in insects. In this review, we discuss several hypotheses on insect phototaxis, factors affecting insect phototaxis, insect‐sensitive wavelengths, biological responses of insects to light, and countermeasures for conserving beneficial insects and increasing the effect of trapping. In addition, we provide information on the different sensitivities to wavelengths causing positive phototactic behavior in > 70 insect pest and beneficial insect species. The use of advanced light traps equipped with superior light sources, such as light‐emitting diodes (LEDs), will make physical pest control in IPM more efficient. © 2019 Society of Chemical Industry  相似文献   

13.
拓宽生物防治 持续治理虫害   总被引:2,自引:0,他引:2  
本文针对我国生物防治资源极其丰富和农民经济实力薄弱的特点,结合我国生物防治成果,论述了应如何发展和拓宽具有我国特色的害虫生物防治,进一步提高综合防治水平,促进农业可持续发展。  相似文献   

14.
鞘翅目昆虫是我国最常见的农林业有害生物,给农林生产造成了巨大损失。基于昆虫趋光性、趋色性和趋化性所研发的昆虫诱捕器作为一种绿色防控手段,目前已广泛应用于农林虫害的监测、预防和控制中,成为了害虫综合防控体系的重要组成部分。明确害虫诱捕装置的设计原理及各因子对诱捕效率的影响是有效实施虫害绿色生物防控的前提,本文陈述了国内外害虫诱捕器的应用进展及设计原理,进而探讨不同因子(如形状、颜色、材质、引诱剂和高度等)对鞘翅目害虫野外诱捕装置诱捕效果的影响,旨在为提高装置诱捕效果提供借鉴和参考,加快新型诱捕技术的研究及应用进程。  相似文献   

15.
The sterile insect technique is an environmentally friendly method to control and even eradicate agricultural and veterinary insect pests without using chemical pesticides in excess. However, the continuous production and release of sterile insects is economically costly and eradication programs using sterile insects have not always been successful owing to the incomplete mating ability of the sterile insects. Here we focus on the theory and empirical findings of interspecific negative mating interaction, known as reproductive interference, to develop a more cost‐effective and value‐added pest management program. We suggest that sterile insects can be used for simultaneous control of both wild‐type conspecifics and closely related pest species by taking advantage of the fact that, when species recognition abilities are incomplete, courtship and mating are often misdirected toward heterospecies. This new approach might help mitigate economic damage and human health crises caused by pest insects. © 2018 Society of Chemical Industry  相似文献   

16.
诱虫作物在害虫治理中的应用   总被引:3,自引:0,他引:3  
诱虫作物主要从物理特性和化学特性两个方面形成比主栽作物更强的引诱力,使主栽作物得以保护。诱虫作物在生产中主要用来诱集害虫、给天敌提供避难和繁殖场所,其作用效果与诱虫作物的品种、播期和田间管理、害虫行为、对天敌的调控、与其他害虫防治方法的有机配合等有重要关系。采用引诱-排斥多策略相结合的方法,研究利用对害虫同时具有诱集和杀灭作用的植物作为诱虫作物,将大大增强诱虫作物在害虫治理中应用的可行性。  相似文献   

17.
USDA-ARS scientists have made important contributions to the molecular genetic analysis of agriculturally important insects, and have been in the forefront of using this information for the development of new pest management strategies. Advances have been made in the identification and analysis of genetic systems involved in insect development, reproduction and behavior which enable the identification of new targets for control, as well as the development of highly specific insecticidal products. Other studies have been on the leading edge of developing gene transfer technology to better elucidate these biological processes though functional genomics and to develop new transgenic strains for biological control. Important contributions have also been made to the development and use of molecular markers and methodologies to identify and track insect populations. The use of molecular genetic technology and strategies will become increasingly important to pest management as genomic sequencing information becomes available from important pest insects, their targets and other associated organisms.  相似文献   

18.
我国农业害虫天敌昆虫利用三十年回顾(下篇)   总被引:1,自引:0,他引:1       下载免费PDF全文
本文参阅了从1985-2014近30年有关我国农业害虫天敌昆虫利用发表的文献,尤其是发表在中国生物防治学报的文章。对天敌资源的调查与分类、优势天敌的人工繁殖与释放、与繁殖和释放相关的基础研究、成功的天敌昆虫引进、生物防治技术应用策略等方面的研究与应用进展进行了简要回顾。期望此文能使读者了解近30年来我国生防前辈所作出的贡献,和后辈继往开来的创新成就;认识农业害虫天敌昆虫在我国农林业生产曾发挥的作用。由于此文篇幅较长,分上、下两篇发表。天敌资源的调查与分类、优势天敌的人工繁殖与释放归为上篇,与繁殖和释放相关的基础研究、成功的天敌昆虫引进、生物防治技术应用策略研究归为下篇。  相似文献   

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