昆虫与弹状病毒互作的研究进展

近年来宏基因组学研究的普及大大丰富了人们对RNA病毒多样性的认识,但对这些新发现病毒的生物学特性却所知甚少。本文围绕RNA病毒中一类重要的负单链RNA病毒--弹状病毒与其昆虫寄主互作的研究进行综述,总结已发现的弹状病毒及其昆虫寄主类型,共有20个属144种弹状病毒可以感染14个属的昆虫;根据已有的系统进化研究对弹状病毒的寄主起源进行推测;并以感染黑腹果蝇Drosophila melanogaster的sigma病毒(Drosophila melanogaster sigma virus,DMelSV)为主要对象,就弹状病毒引起的CO2麻痹致死症状以及昆虫寄主对其的免疫反应研究进行总结,而在对黑腹果蝇的研究中发现很多非经典免疫通路中的新抗病毒基因,暗示存在新的抗病毒免疫通路;通过飞虱、叶蝉与其传播的植物弹状病毒以及长须罗蛉Lutzomyia longipalpis与其传播的脊椎动物病毒的互作研究,发现Toll、IMD信号通路、细胞自噬及小RNA干扰(small interfering RNA,siRNA)通路等可能与昆虫对弹状病毒的免疫反应相关。昆虫是弹状病毒主要的寄主和媒介,也是病毒遗传多样性的储主,因此更好地研究和了解昆虫寄主与弹状病毒的相互关系,有助于病毒致病和传播机制以及昆虫抗病毒免疫机理的深入研究。     

葡萄A病毒外壳蛋白原核表达及抗血清制备

 葡萄A病毒（Grapevine virus A,GVA）为线性病毒科（Flexiviridae）葡萄病毒属（Vitivirus）的代表种,是葡萄皱木复合病（rugose wood complex disease）的重要病原之一,可引起葡萄嫁接成活率下降、春季萌芽延迟、生长减弱甚至衰退死亡等危害\[1,2\]。GVA为线状单链RNA病毒,基因组共编码5个开放阅读框（ORF1\|5）,其中ORF4 编码外壳蛋白（coat protein, CP）,是病毒粒子包裹和系统移动所必需的功能蛋白\[3,4\]。GVA自然寄主为葡萄,机械摩擦可侵染本氏烟等草本寄主\[2\],由于嫁接和无性繁殖材料调运等因素造成该病毒远距离传播,目前在世界多个国家和地区均有发生。     

甘蔗黄叶病及其病原分子生物学研究进展

甘蔗黄叶病是由甘蔗黄叶病毒(Sugarcane yellow leaf virus,SCYLV)引起的一种病毒病害,在全球主要甘蔗种植国家或地区普遍发生,危害日益严重。SCYLV经甘蔗蚜虫以持久性方式传播,在寄主植株内主要侵染韧皮部组织。该病毒起源于黄症病毒科属间基因重组,被国际病毒分类命名委员会确认为黄症病毒科马铃薯卷叶病毒属成员。文章综述了甘蔗黄叶病毒生物学特征、病害发生和危害、病原鉴定和检测、分子进化和遗传多样性、基因组结构和基因功能以及抗病转基因等方面研究进展,并对甘蔗黄叶病抗病育种和防治措施作了讨论。     

中国植物弹状病毒研究进展

弹状病毒含有单链负义RNA基因组,寄主范围比较广泛,能侵染无脊椎动物、脊椎动物以及植物等寄主,对人类的健康、农作物产量和自然生态系统造成严重威胁。植物弹状病毒主要根据复制场所分为细胞质弹状病毒属Cytorhabdovirus和细胞核弹状病毒属Nucleorhabdovirus,其基因组由单股负链RNA组成。此外,Dichorhavirus和Varicosavirus病毒属是两个新鉴定的植物弹状病毒属,其特征是具有二分体基因组。本文着重介绍危害我国农作物的几类植物弹状病毒,对它们的病理学、病害流行、基因组信息以及传播媒介进行概述,为中国植物弹状病毒病害的研究提供理论依据。     

ICTV第八次报告的最新植物病毒分类系统

 本文介绍了国际病毒分类委员会第八次报告中的最新植物病毒分类系统18个科、81个属,以及亚病毒感染因子的类病毒和病毒卫星。与第七次报告相比新增的3个科、9个属分别是:矮缩病毒科、芜菁黄花叶病毒科、线形病毒科、番茄伪曲顶病毒属、香蕉束顶病毒属、塞尔病毒属、内源RNA病毒属、葡萄斑点病毒属、柑橘病毒属、葡萄卷叶病毒属、温州蜜柑矮缩病毒属、樱桃锉叶病毒属。     

西瓜和甜瓜上西瓜银斑驳病毒的鉴定及广西分离物S RNA序列分析

<正>0引言西瓜银斑驳病毒(watermelon silver mottle virus,WSMoV)是番茄斑萎病毒科(Tospoviridae)正番茄斑萎病毒属(Orthotospovirus)病毒，主要通过蓟马以持久增殖型方式传播^[1-2]。WSMoV病毒粒子球状，外具包膜，基因组为三分体负单链RNA，分别为L RNA、M RNA和S RNA^[1,3]。1982年IWAKI等最先在日本冲绳县发现WSMoV为害西瓜，在叶片上产生银色斑驳症状，遂命名为西瓜银斑驳病毒^[4]；随后，中国台湾、泰国、印度等地陆续报道该病毒^[1,5-6]。     

苹果褪绿叶斑病毒辽宁分离物生物学和基因组研究

正苹果褪绿叶斑病毒(Apple chlorotic leaf spot virus,ACLSV)属于乙型线形病毒科(Betaflexiviridae)纤毛病毒属(Trichovirus),基因组为正义单链RNA,含有约7 500个核苷酸,编码3个部分重叠的开放阅读框。目前从Gen Bank数据库可以检索到19个ACLSV分离物的基因组序列。该病毒侵染仁果与核果,如苹果和桃,在苹果栽培种上不引起症状,在特定指示植物上引起症状,如俄罗斯苹     

亚洲柑橘木虱中柑橘黄脉病毒的鉴定

<正>柑橘黄脉病毒(citrus yellow vein clearing virus,CYVCV)为正单链RNA病毒，属于α线性病毒科Alphaflexiviridae印度柑橘病毒属Mandarivirus成员，病毒粒子为弯曲线状，基因组大小约为7 529 nt^[1]。CYVCV可侵染大部分柑橘品种，对柠檬和酸橙危害尤为严重。CYVCV 2009年在我国首次发现，现已在我国柑橘主产区均有发生，已知的传媒昆虫为柑橘粉虱(Dialeurodes citri)和棉蚜(Aphis gossypii)^[2-4]。     

玉米小斑病菌中一种维多利亚病毒的分离及其基因组全序列分析

 从玉米小斑病菌(Bipolaris maydis)中检测发现一种dsRNA (double-stranded RNA)病毒,暂命名为Bipolaris maydis victorivirus 2 (BmV2)。电子显微镜下观察到病毒粒子为二十面体球状,直径为40 nm左右、无包膜;病毒基因组为单条dsRNA核酸分子,长度为5 222 bp,其基因组结构与其他维多利亚病毒相似,包含两个开放阅读框(ORFs)。序列BLASTx分析发现,BmV2的基因组核酸序列与Coniothyrium minitans RNA virus Illinois isolate (CmRV-IL)具有较高的同源性(78.15%),后者CmRV-IL是单分体病毒科(Totiviridae)维多利亚病毒属(Victorivirus)的暂定种,两者的外壳蛋白(CP)和RNA依赖性RNA聚合酶(RdRp)的氨基酸序列之间的同源性分别为88.02%和89.87%,说明BmV2、CmRV-IL是同一种病毒的不同分离物。基于BmV2和选择的单分体病毒的RdRp氨基酸序列的系统发育分析表明,BmV2与单分体病毒科维多利亚病毒属中的病毒形成了一个单系进化支。     

油茶炭疽菌携带病毒种类鉴定及多样性分析

 炭疽菌是重要的植物病原真菌,能够引起多种植物炭疽病。真菌病毒广泛存在于植物病原菌中,侵染炭疽菌属真菌的病毒资源有待挖掘。本文利用宏病毒组测序技术,对分离自我国南部6个省份不同油茶园的40株油茶炭疽菌中的病毒进行了鉴定。经过同源比对分析,发现10种基因组类型均为正义单琏RNA的新病毒。它们分属于减毒病毒科(Hypoviridae)、裸露病毒科(Narnaviridae)、线粒体病毒科(Mitoviridae)和葡萄孢欧尔密病毒科(Botourmiaviridae)。本研究是我国南方油茶炭疽病菌携带病毒的首次报道。研究结果丰富了炭疽菌属所携带的病毒基因组信息,可为深入分析炭疽菌真菌病毒的多样性和分子特性奠定基础。     

Contribution of Biological Control to Integrated Pest Management of Tephritid Fruit Flies in the Tropics and Subtropics

The biological control of pest tephritid flies using parasitoids has been successful in relatively few subtropical and tropical regions. The best documented successes were in Hawaii and Florida, USA, Fiji and southern Europe. There were relatively limited successes in Australia, Costa Rica and Mexico. With the accidental establishment of new pest tephritids, such as Bactrocera latifrons (Hendel) in Hawaii or Bactrocera papayae Drew and Hancock in Australia, foreign exploration for new parasitoids is essential. A renewal of interest in classical biological control has recently occurred, although not at the same level as in the 1940s and 1950s. New parasitoid species are currently being obtained for several tephritids, such as Ceratitis capitata (Weidemann), B. latifrons and Anastrepha suspensa (Loew). The advances in mass rearing and quality control technology for parasitoids has enabled researchers to perform large-scale field testing of these parasitoids to determine the potential of augmentative releases. Numerous studies on the augmentative release of parasitoids have been done. Historically, the larval—pupal parasitoid Diachasmimorpha longicaudata (Ashmead) has been the most frequently studied parasitoid, due to the ease of rearing this species. However, recent successes in rearing other species with different biologies, e.g. the egg—pupal parasitoid Biosteres arisanus (Sonan), the gregarious eulophid, Tetrastichus giffardianus (Silvestri) and the pupal parasitoid, Coptera sp., will enable researchers to broaden the repertoire of parasitoid species for the future. Both successes and failures in augmentative releases have occurred. Without knowledge of the behavioural ecology of parasitoids, the reasons for success or failure can only be surmised. Recent research on the dispersal and host habitat finding of tephritid parasitoids will provide insights into improving augmentation and conservation strategies. The integrated pest management (IPM) of tephritid flies in the tropics has been less well-developed than research and programmes for tephritids in temperate zones. Significant emphasis is now being placed on the development of quarantine treatment methods that are environmentally sound; thus IPM will take a larger role. Several existing pest management strategies are reviewed which show the potential for compatibility with the activities of tephritid parasitoids. These include trap cropping, insecticides with selective toxicity to the target pests, mass trapping with parapheromones, the sterile insect technique and field sanitation.     

Gut sugar analysis in field-caught parasitoids: Adapting methods originally developed for biting flies

The ability to determine the presence and identity of sugars in the guts of adult parasitoids in the field would aid researchers in addressing long-standing problems in parasitoid ecology. Until very recently, however, gut sugar analyses have not been carried out on parasitoids. This is despite the development and use of methodologies for gut sugar analyses in biting flies (mosquitoes, sand-flies, black-flies, horse- and deer-flies, and biting midges) for decades. Methods used have been the cold anthrone test for the detection of gut sugars, and various forms of chromatography for the identification of gut sugars. We review the use of these methods in biting fly research and then describe the nascent field of gut sugar analyses in parasitoids. Both cold anthrone and chromatography tests have begun to be used on field-caught parasitoids, and we describe progress from our own work. We used cold anthrone on the aphid parasitoid Aphelinus albipodus (Hymenoptera: Aphelinidae), and results from one field study show that approximately one-fifth of individuals tested were positive for gut sugars. The characteristics of the field site point to the primary source of these gut sugars as being aphid honeydew. We also analysed the gut contents of Diadegma insulare (Hymenoptera: Ichneumonidae), a parasitoid of diamondback moth. In this case, HPLC analyses showed that over 85% of field-captured individuals had fed upon sugars. These same analyses suggested that honeydew may have been a major source of the gut sugars in this case also, but the sugar profiles suggest some nectar feeding. Understanding the importance of various sugar sources on parasitoid activity and effectiveness will facilitate the incorporation of sugar sources in habitat manipulation programmes as a part of IPM.     

Toxicity and sublethal effects of an insecticidal soap on Aphidius colemani (Hymenoptera: Braconidae)

BACKGROUND: The effects of an insecticidal soap on the survival, fitness and behaviour of an aphid parasitoid wasp, Aphidius colemani (Viereck), were studied in the laboratory. The LC(50) (soap concentration causing 50% mortality 24 h after treatment) was determined. The survival of parasitoid larvae (% adult emergence), fitness (tibia length of adults) and number of eggs produced per female parasitoid that survived in third- and fourth-instar aphids treated with insecticidal soap LC(50) were also assessed. The LC(50) for third- and fourth-instar aphids was determined to be 3.25 g L(-1). Acceptance by female parasitoids of aphids that survived their LC(50) was also tested. RESULTS: The soap concentration causing 100% mortality in adult wasps 24 h after treatment was 17.5 g L(-1). The LC(50) was 2.75 g L(-1). Soap did not have any effect on the survival of parasitoid immatures or on the fitness or number of eggs produced per female parasitoid. Wasps that were in contact with treated aphids did not oviposit as much in them as in untreated aphids, indicating that female parasitoids detected aphids treated with insecticidal soap. CONCLUSION: These data suggest that aphid parasitoids released following treatment with insecticidal soap are likely to accept a lower proportion of the surviving aphids. Biological control programmes could be ameliorated by soap applications if the latter were made 1 day before the release of wasps in the greenhouse.     

Hymenoptera wasps associated with the Asian gall wasp of chestnut (Dryocosmus kuriphilus) in Calabria,Italy

The parasitoid complex of the Asian chestnut gall wasp Drycosmus kuriphilus Yasumatsu was studied in Calabria (Italy). A total of 14 different species of parasitoids were collected, of which three are recorded on the Asian gall wasp for the first time. The composition of the parasitoid complex collected in Calabria was compared with that reported from Italy and from Europe. The altitude of the sites of collection seemed to have an effect on the distribution and abundance of the single species of parasitoids.     

Manipulation of parasitoids for aphid pest management: progress and prospects

This paper describes research at IACR-Rothamsted on aphid parasitoid responses to semiochemical foraging stimuli, aimed at developing novel ways of manipulating these behaviours to overcome ecological constraints to biological and integrated pest control. Female parasitoids respond both to aphid sex pheromones acting as kairomones, and to aphid-induced plant volatiles, acting as synomones. A range of economically important parasitoid species respond to aphid sex pheromones, and their potential for enhancing parasitization of aphid populations has been demonstrated in the field. Commercial production of the pheromone from the plant Nepeta cataria L has been developed and strategies for its use in arable crops are being investigated. Aphid-induced plant volatiles are released systemically throughout the plant and are aphid species specific, probably induced by elicitors in aphid saliva. Aphid-infested plants can induce uninfested neighbours to release damage-related volatiles, plant-to-plant communication occurring via the rhizosphere. The plant compound cis-jasmone has been identified as a plant signal with potential for aphid control, inducing plant defence mechanisms that both deter colonising aphids and attract parasitoids and predators. Such compounds may represent a new generation of crop protectants and their further investigation and development will be aided by the tools generated by genomic and post-genomic biology.     

桔小实蝇的寄生蜂及其应用

就桔小实蝇寄生蜂种类、生物学特性、寄主选择行为、农药对寄生蜂的影响及寄生蜂在生物防治中的应用等方面的研究进展进行了较全面的综述.     

植物挥发物在寄生蜂寄主定位中的作用

植物挥发物在寄生蜂的寄主栖息地定位中起着重要作用。在自然状态下,某些健康植物能释放对寄生蜂有吸引作用的挥发物。当植物受到植食性昆虫为害后,可引起植物的间接防御,即产生对一定种类寄生蜂具引诱作用的挥发物来保护自己。此外,害虫的产卵也能诱导部分植物产生引诱天敌的物质。对于植食性昆虫取食植物诱导的挥发物研究较深入,而其产卵对植物挥发物的影响研究较少。本文主要综述近年国内外有关植物挥发物对寄生蜂寄主定位影响的研究概况,可望为害虫综合治理研究提供参考。     

美洲斑潜蝇寄生蜂研究概况

本文综述了美洲斑潜蝇寄生蜂的研究概况,包括寄生蜂的种类、生物学、寄主选择特性,寄生蜂与植物的关系,化学农药对寄生蜂的影响,以及寄生蜂的保护和利用。