三种重要皮蠹科害虫的幼虫形态与分子鉴定

为寻求白腹皮蠹和赤毛皮蠹幼虫简便科学的鉴定方法,利用形态学结合分子生物学对其做了鉴定研究,首先对其触角、上内唇、臀突和胸足胫节的特征进行了形态描述;再分别提取白腹皮蠹、赤毛皮蠹和外群黑毛皮蠹幼虫的虫体DNA进行PCR扩增,通过测序比对构建了系统进化树。结果表明:白腹皮蠹幼虫上内唇的中间2根缘刚毛呈蘑菇状,粗短,而赤毛皮蠹幼虫的则呈矛状,细长,二者上内唇的形态特征差异非常明显,可用于二者形态上的鉴定;对3种皮蠹幼虫的序列进行比对,白腹皮蠹与赤毛皮蠹的碱基相似率为89.97%,黑毛皮蠹与白腹皮蠹和赤毛皮蠹的碱基相似率分别为77.54%和77.05%,差异均明显,可用于3种皮蠹幼虫种间鉴定的线粒体COⅠ基因标记序列。     

甘蔗簇粉蚧的形态和分子鉴定

为了准确快速鉴定甘蔗簇粉蚧,利用显微技术对虫体进行观察,再提取单头粉蚧基因组DNA,应用COI通用引物进行PCR扩增并双向测序。PCR产物测序分析后,输入GenBank中进行BLAST搜索并应用MEGA11构建系统发育树。结果表明甘蔗簇粉蚧主要形态特征为具有18对刺孔群,钉状单孔散布背面,多格腺少,仅在阴门附近,领状管腺无。所获得的COI基因序列与甘蔗簇粉蚧具有100%一致性,系统发育分析表明样品的COI基因序列均与甘蔗簇粉蚧处于同一分支中。研究结果可为该类粉蚧的检疫鉴定提供参考。     

草地螟幼虫和蛹的形态特征及雌雄鉴别方法

草地螟雌、雄成虫的形态特征及鉴别方法在室内研究及种群测报中已经广泛应用,但幼虫及蛹的形态特征及雌雄的鉴别方法目前尚没有报道。本文借助超景深三维显微系统,观察不同龄期草地螟幼虫的形态特征、5龄幼虫性别特征以及雌、雄蛹的区别,以期为草地螟幼虫和蛹的形态识别和性别鉴定提供科学分类依据。研究表明:1)初孵幼虫体色为淡黄色,随着龄期增大,体色逐渐加深,至末龄为灰黑色或黑色,3龄出现白斑和体侧纵带,5龄体背出现2条鲜黄色或黄白色背线;2)雄幼虫第5腹节背管两侧有一对精巢,呈白色半透明橘瓣状,3片精小囊隔膜将精巢分为4个小腔室,预蛹期2个精巢逐渐靠拢、融合并发生扭转,蛹期完全融合成为一个不可剥离的圆球体,直至生命结束;雌幼虫卵巢没有明显分化;3)雌蛹腹部8～10节分节不明显,第8腹节中央的生殖孔和第9腹节的产卵孔连接组成一纵裂缝,裂缝两侧平坦,裂缝下端与排泄孔上端距离较远,为(0.48±0.005)mm,腹部末端钝圆;雄蛹腹部8～10节分节明显,第8腹节无纵裂缝,第9腹节的生殖孔呈一纵裂缝与第10腹节相连,裂缝两侧各有一个半圆形瘤状突起,裂缝下端与排泄孔上端距离较近,为(0.24±0.005)mm,腹部末端较尖。     

危害红掌的穿孔线虫形态和分子鉴定

对一批引进后隔离培养中患病的红掌种苗,进行了根系线虫检测,通过病症分析、线虫形态测量、rDNA-ITS区序列分析等鉴定,结果表明:检测的线虫形态和香蕉穿孔线虫基本一致,rDNA-ITS区测序结果序列一致性为98％～100％.本报道再次证明香蕉穿孔线虫在红掌上的分布和危害,应该对种苗的跨区引进和种植过程进行严格的检疫.     

欢迎订阅《伞滑刃属线虫形态和分子鉴定》

该书紧密围绕进境木质包装检疫工作,反映了国际伞滑刃属线虫研究的最新成果。该书分6章,第一章概述,介绍了分类背景、鉴定方法及检疫意义;第二章介绍属内两种重要检疫对象——松材线虫和椰子红环腐线虫;第三章介绍伞滑刃属线虫种类与分布,列出了95种线虫名录;第四章在核糖体DNA序列分析     

大黑粉盗幼虫和蛹的形态特征

大黑粉盗目前已成为储藏谷物尤其是玉米的重要害虫。本文描述了大黑粉盗幼虫和蛹的形态特征。大黑粉盗与其他储藏物甲虫幼虫的区别为:中、后胸背板无前横隆线,腹末节背板背面观呈三角形,由前向后狭窄,端部尖,端部两侧各具1对粗短刚毛。大黑粉盗蛹的主要鉴别特征有:前胸背板表面具许多微小锥形刚毛瘤,基部1/4处中央两侧具1对大刚毛瘤,前缘和侧缘具许多小锥形刚毛瘤和少量大刚毛瘤;第1~7腹节背板具较宽大侧叶突,第2~6腹节侧叶突前后缘均呈锯齿状,侧缘前半部分具2长刚毛瘤,且通常在其间有1小刚毛瘤,后角具1长刚毛瘤,第1腹节侧叶突前缘光滑,第7腹节侧叶突特别狭窄,后方弯曲后缘缺失,第8腹节侧缘平均分布3刚毛。     

基于DNA条形码的广西苦瓜中实蝇幼虫分子鉴定研究*

实蝇是多种热带、亚热带水果和蔬菜的重要害虫,其卵、幼虫、蛹难以通过形态特征进行种类鉴定。DNA条形码是近年来出现的物种分子鉴定技术,能够实现对昆虫非成熟虫态的快速鉴定。本研究利用DNA条形码技术和BOLD系统,选取线粒体DNA细胞色素氧化酶I（COI）基因片段,针对采自于广西南宁地区苦瓜中的实蝇幼虫样品进行了序列测定、比对和分析。结果显示,在所检测的10头实蝇幼虫样品中,有4头为瓜实蝇［Bactrocera cucurbitae (Coquillett)］、6头为南亚果实蝇［Bactrocera tau (Walker)］。     

日本鸡爪槭中旱稻胞囊线虫形态和分子鉴定

从宁波口岸进境的日本鸡爪槭(Acer palmatum)景观树根际介质中分离到1种胞囊线虫属的2龄幼虫,通过形态鉴定和分子特征分析,鉴定其为旱稻胞囊线虫(Heterodera elachista Ohshima,1974)。该日本群体的2龄幼虫体长374~421μm;唇区有3个唇环;口针粗壮,长16.5~19.2μm,基部球圆形或前端略凹陷;侧线3条;尾长圆锥形,末端细圆,透明尾长22.9~30.7μm,约占尾长的50%。基于核糖体DNA的28S-D2/D3区和ITS区序列构建的系统发育树以及ITS序列酶切分析证实该鉴定结论,这是我国首次截获旱稻胞囊线虫。     

基于DNA条形码技术的泰国番石榴中实蝇幼虫分子鉴定研究

实蝇是世界重要的检疫性害虫之一,对果蔬生产及其国际贸易具有很大的影响。而以线粒体DNA细胞色素C氧化酶亚单位I(mtDNACOI)基因的部分序列作为实蝇的DNA条形码能减少对实蝇成虫形态特征的依赖,可检测其任何虫态的样品,有助于实蝇样品的快速鉴定。本研究采用DNA条形码技术,针对采自泰国四色菊市番石榴烂果中的5头实蝇幼虫进行COI扩增测序,与生命条形码数据库(BOLD)中的序列进行比对并利用PAUP4.0软件构建了其系统进化树。根据序列分析和系统进化关系分析的结果,将5头实蝇幼虫样品鉴定为番石榴实蝇(Bactrocera correctaBezzi),并将本研究获得的2条COI序列在GenBank中注册,GenBank的登录号为HM590450和HM590451。     

墨西哥斑皮蠹幼虫形态特征识别

墨西哥斑皮蠹是一种危害性很大的杂食性仓库害虫。我国尚无记载。其幼虫形态特征描述目前国内尚无报导。该幼虫与同属常见的谷斑皮蠹、花斑皮蠹、黑斑皮蠹幼虫在形态特征上极为相似,外观难以区别。本文对墨西哥斑皮蠹幼虫形态特征进行较详细的描述,并以检索表形式与同属3个常见的近似种进行鉴别。     

Broad-spectrum insecticide resistance in obliquebanded leafroller Choristoneura rosaceana (Lepidoptera: Tortricidae) from Michigan

Nineteen insecticides, belonging to nine chemical classes, were bioassayed by dietary exposure against two strains of obliquebanded leafroller, Choristoneura rosaceana, collected from Michigan apple orchards. Berrien is a putatively organophosphate-resistant strain from a commercial orchard with a history of insecticide use, and Kalamazoo a susceptible strain from an isolated and unsprayed orchard. The Berrien strain was moderately resistant (about 25-fold) to organophosphates such as azinphos-methyl and chlorpyrifos. Very low resistance (< 10-fold) was also observed to pyrethroids such as cypermethrin, zeta-cypermethrin, bifenthrin, deltamethrin and esfenvalerate, to the ecdysone agonists tebufenozide and methoxyfenozide, and to the chlorinated pyrrole chlorfenapyr. Endosulfan and carbamates such as thiodicarb, methomyl and carbaryl had low intrinsic toxicities against both strains, with little difference in sensitivity between them. There was no resistance to spinosad. Emamectin benzoate was found to be the most toxic insecticide against C rosaceana, with slightly higher lethal doses required for the Berrien strain. Unexpectedly, Berrien exhibited a very high level of resistance (> 700-fold) to indoxacarb, which has never been used in Michigan to control this insect pest. The active metabolite of indoxacarb, DCJW, was considerably more toxic than the parent compound, but the resistance against DCJW was comparable to that seen with indoxacarb. This indicates that a failure to activate indoxacarb was not the mechanism of resistance in Berrien. The low level of resistance to several chemistries recorded in Michigan C rosaceana can be managed at this stage by adopting a rotation of chemistries having different modes of action.     

Mechanisms of resistance to organophosphorus insecticides in populations of the obliquebanded leafroller Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae) from southern Ontario

Populations of Choristoneura rosaceana (Harris) from orchards in Ontario were shown to be resistant to azinphos-methyl and to other types of organophosphorus insecticides. Resistance extended to methyl carbamates and to methomyl. The laboratory population used for these assays and selected with azinphosmethyl was also resistant to the pyrethroid, cypermethrin. Resistance was associated with increased esterase activity and was reduced by the addition of the synergist DEF. IEF studies of esterases also indicated increased activity in resistant populations, but did not identify any unique esterases associated with the resistance. Resistance was highly correlated (r = 0.78) with elevated esterases but not with increased glutathione-S transferase activity (r = 0.13). Other mechanisms did not appear to be related.     

Impact of sub-lethal residues of azinphos-methyl on the pheromone-communication systems of insecticide-susceptible and insecticide-resistant obliquebanded leafrollers Choristoneura rosaceana (Lepidoptera: Tortricidae)

The effects of sub-lethal residues of azinphos-methyl on pheromone production, calling, female attractiveness and the ability of males to locate sources of natural and synthetic pheromone were compared in azinphos-methyl-susceptible (susceptible) and azinphos-methyl-resistant (resistant) obliquebanded leafrollers, Choristoneura rosaceana (Harris). The amount of pheromone in susceptible females was reduced by 29-33% after exposure to azinphos-methyl; this treatment did not affect the pheromone content of resistant females. Azinphos-methyl-treated resistant females contained 39-43% less pheromone than azinphos-methyl-treated susceptible females. Resistant females that were not treated with azinphos-methyl contained 35-56% less pheromone than susceptible females that were not treated with insecticide. The incidence of calling was reduced by 67-100% in azinphos-methyl-treated susceptible females; the incidence of calling by resistant females was not affected by exposure to azinphos-methyl. The incidence of calling by azinphos-methyl-treated susceptible females was 58-100% lower than that of azinphos-methyl-treated resistant females. There was no difference in the incidence of calling between susceptible and resistant females that had not been treated with insecticide. In a flight tunnel, treatment with insecticide reduced the attractiveness of susceptible females by 38%; treatment with insecticide did not affect the attractiveness of resistant females. There was no difference in the proportion of males attracted to susceptible and resistant females that had, or had not been treated with insecticide. In an apple orchard, the attractiveness of susceptible and resistant females treated with azinphos-methyl was reduced by 84 and 12%, respectively. The proportion of males attracted to azinphos-methyl-treated susceptible females was 58% lower than the proportion attracted to azinphos-methyl-treated resistant females, whereas, if females were not treated with insecticide, the proportion attracted to resistant females was 57% lower than the proportion attracted to susceptible females. In a flight tunnel, azinphos-methyl did not affect the ability of susceptible or resistant males to locate a source of pheromone gland extract. Likewise, in an apple orchard, the insecticide treatment had no effect on the ability of susceptible or resistant males to locate a source of synthetic pheromone. In a flight tunnel, there was no difference in the proportion of azinphos-methyl-treated susceptible and resistant males locating a source of pheromone gland extract; however, in the orchard, 39% fewer azinphos-methyl-treated resistant males located a source of synthetic pheromone than azinphos-methyl-treated susceptible males. A similar proportion of susceptible and resistant males that had not been treated with insecticide located a source of pheromone gland extract in the flight tunnel, but in the orchard, the proportion of resistant males not treated with azinphos-methyl that located the source of synthetic pheromone was 32% lower than the proportion of susceptible males not treated with this insecticide. The implications of the differences in the effect of sub-lethal residues of azinphos-methyl on the pheromone communication system of susceptible and resistant moths are discussed in relation to the theory of the development of insecticide resistance, the detection of resistance in feral populations of moths using sex pheromone-baited traps, and the control of moths using sex pheromone-mediated mating disruption.     

Synergism of insecticides provides evidence of metabolic mechanisms of resistance in the obliquebanded leafroller Choristoneura rosaceana (Lepidoptera: Tortricidae)

The interactions between six insecticides (indoxacarb, cypermethrin, chlorpyrifos, azinphosmethyl, tebufenozide and chlorfenapyr) and three potential synergists, (piperonyl butoxide (PBO), S,S,S-tributyl phosphorotrithioate (DEF) and diethyl maleate (DEM)) were studied by dietary exposure in a multi-resistant and a susceptible strain of the obliquebanded leafroller, Choristoneura rosaceana (Harris). The synergists did not produce appreciable synergism with most of the insecticides in the susceptible strain. Except for tebufenozide, PBO synergized all the insecticides to varying degrees in the resistant strain. A very high level of synergism by PBO was found with indoxacarb, which reduced the resistance level from 705- to 20-fold when PBO was administered alone and to around 10-fold when used in combination with DEF. DEF also synergized indoxacarb, cypermethrin, chlorpyrifos, azinphosmethyl and tebufenozide in the resistant strain. DEM produced synergism of indoxacarb, chlorpyrifos, azinphos-methyl and chlorfenapyr in the resistant strain. DEM was highly synergistic to cypermethrin, and to some extent to tebufenozide in both the susceptible and resistant strains equally, implying that detoxification by glutathione S-transferases was not a mechanism of resistance for these insecticides. The high level of synergism seen with DEM in the case of cypermethrin may be due to an increase in oxidative stress resulting from the removal of the antioxidant, glutathione. These studies indicate that enhanced detoxification, often mediated by cytochrome P-450 monooxygenases, but with probable esterase and glutathione S-transferase contributions in some cases, is the major mechanism imparting resistance to different insecticides in C. rosaceana.     

苹果异形小卷蛾的分子鉴定研究

苹果异形小卷蛾（Thaumatotibia leucotreta）是世界范围内重要的检疫性有害生物,对水果和农作物等生产具有重要影响,并影响国际贸易发展。本研究选用线粒体 COI 基因作为物种鉴定的条形码,结合 GenBank 数据库、BOLD 数据库比对和系统进化树构建,对2014年1月广州白云国际机场口岸入境加纳牛油果中截获的卷蛾科昆虫进行分子鉴定。根据 GenBank 数据库比对分析、NJ方法构建的系统进化树分析以及 BOLD 数据库查询分析,最终鉴定该样品为苹果异形小卷蛾。认为基于 DNA 条形码的分子鉴定能快速、准确地鉴定苹果异形小卷蛾。     

无花果树苗中截获的无花果孢囊线虫形态和分子鉴定

上海口岸从旅客携带进境的树苗中分离到1种孢囊线虫属的2龄幼虫,通过形态特征和分子特征分析,鉴定为无花果孢囊线虫(Heterodera fici Kirjanova,1954)。该2龄幼虫的主要形态特征为:体长409.9~454.4μm;唇环3个;口针发达,长22.6~24.0μm,基部球圆形略向前倾斜;侧线4条;尾长圆锥形,末端细圆,尾部透明区长24.7~30.5μm,约占尾长的1/2。序列分析显示其ITS区序列与GenBank中无花果孢囊线虫的序列相似性为99.48%~99.90%,序列差异为1~5 bp。系统发育分析显示该线虫与无花果孢囊线虫处于一个聚类组内。这是我国口岸首次报道截获无花果孢囊线虫。     

Effects of kaolin-based particle film on spruce budworm (Choristoneura fumiferana (Lepidoptera: Tortricidae)) oviposition in the laboratory

A laboratory study conducted in 2003 determined the influence of a kaolin-based particle film (Surround WP Crop Protectant) on spruce budworm (Choristoneura fumiferana (Clem)) oviposition. Three concentrations (15, 30 and 60 g litre(-1) spray carrier) were applied to white spruce (Picea glauca (Moench) Voss). When presented with different paired choices of oviposition surfaces, spruce budworms laid very few egg masses overall and showed no significant (P < 0.05) preference between kaolin-coated and untreated foliage. During no-choice tests, spruce budworms were significantly (P < 0.05) less inclined to oviposit on the 60 g kaolin litre(-1) treated foliage than on the controls, but no kaolin treatment completely inhibited spruce budworm oviposition. Egg mass size and percentage hatch were unaffected by the kaolin treatments, and overall the percentage of egg masses laid on foliage was inversely proportional to treatment concentration. It is unlikely that kaolin-based particle film would be practical for wide use in natural forests without significant adaptations to current pesticide application equipment and methods. However, the technique might be feasible in selected urban settings.