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关于昆虫的文献

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关于昆虫的文献

这种昆虫对人类危害极大,破坏力极其强能吃各种东西甚至金属

昆虫对人类有些什么影响?昆虫对人类的影响十分广泛和复杂,既对人类有益有对人类有害。一、昆虫对人类提供有益的服务1、昆虫为人类提供食品和工业原料。有一些昆虫自身的产物,如蜂蜜、蚕丝、白蜡、染料、色素等是人类的食品及工业的原料。2、昆虫为农作物、树木提供传媒手段。昆虫农作物、树木、花卉的繁殖提供花粉传播,全世界有2/3有花植物靠昆虫传播花粉。3、昆虫为生态系统平衡的重要一环。世界上有3%的昆虫食腐败的生物有机体和动物排泄物。在生态系统中,昆虫能分解大量的枯枝落叶、动物尸体,以及大量废物,把它们送回土壤完成物质循环。4、昆虫为动物生存提供平衡作用。世界上有4%昆虫是寄生的,寄生在其它昆虫或动物体外和体内。有一些哺乳动物在生长过程中,要靠昆虫捕捉体表的寄生虫;有一些动物靠昆虫消化食物;所以昆虫在维持某些动植物之间的平衡起着重要作用。二、昆虫对人类造成的危害1、昆虫与人类生存争夺粮食。昆虫每年大量地毁掉人类的粮食及农产品(收获前与收获后),世界上每年至少有20~30%的农产品被昆虫吃掉。2、昆虫破坏房屋建筑。昆虫大量生存在建筑物的屋顶、屋内、地面;特别是木结构房屋常常被昆虫侵蚀,使建筑物减少寿命。3、昆虫传播疾病。昆虫传播人体或人畜疾病的能力极强,世界上有很多病毒的传播,都是由昆虫进行的。4、昆虫大量毁坏植物。昆虫中有2%是植食性的,在小范围内很容易被人们忽略,当大面积虫灾发生时,可以将千亩良田毁于一旦;百顷树木灭绝。

昆虫记

具体如下,请你参考:有害方面:不少是农林植物及仓贮等的重要害虫如危害禾谷作物的东亚飞蚯、粘虫、稻飞虱、稻纵卷叶螟等;棉花害虫如棉蚜、棉红铃虫等;危害蔬菜的菜青虫、小菜蛾等;危害森林的五尾松松毛虫、松墨天牛等;仓贮害虫如玉米象、蚕豆象等此外,白蚁严重危害建筑物、堤坝、桥梁、枕木等还有不少昆虫危害人畜健康,人的传染病有2/3以昆虫为媒介,如鼠疫、斑疹伤寒等蚊子、跳蚤、虱子、牛虻、刺蝇等为吸血昆虫,厩蝇可刺吸牛、马血液,并传染疾病

关于昆虫的杂志

《昆虫分类学报》《应用昆虫学报》

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很多的,可以到天地人教育咨询网络看看

昆虫学报华东昆虫学报你上图书馆了解一下就都知道了

有关昆虫的文献

鸟给人的启示 鸟对人类的贡献是众所周知的。鸟类还有一种特殊的作用,这就是它启发了人类的智慧,为人类探求理想的技术装置或交通工具,提供了原理和蓝图。可以说,在结构、功能、通讯等方面,鸟类是人类的老师,许多现代科学技术问题,科学家常常需要去请教鸟类。 鹰击长空,鸽翔千里,鸟类可以在空中自由飞行,这对人类是多么大的吸引和激励啊!传说,在2000多年前,我国的著名工匠鲁班,曾研究和制造过木鸟。据历史文献记载,1900多年前,我国就有人把鸟羽绑在一起,做成翅膀,能够滑翔百步以外。400多年以前,意大利人达·芬奇根据对鸟类的观察和研究,设计了扑翼机,试图用脚蹬的动来扑动飞行。后来,经过许多科学家的试验,人们才弄清鸟类定翼滑翔的机理,认识到机翼必须像鸟翼那样前缘厚,后缘薄,构成曲面才能产生升力,再加上工业提供了轻质的金属材料和大功率发动机,终于在1903年发明了飞机,实现了几千年来人类渴望飞上天空的理想。 人类自从发明了飞机,飞上天空以后,就在不断地对飞机进行革新改造,不论是体积、载重、速度,都很快超过了鸟类。现代飞机已经比任何鸟类都飞得更快、更远、更高,尤其是近年来出现的各种飞行器,可以到星际间航行,更是鸟类所望尘莫及的。尽管这样,在某些飞行技术和飞行器的结构上,人造的飞机仍然不如鸟类那么完善而且精致,更不要说消耗能源方面了。例如,金鸻可以连续在海洋上空飞行4000多公里,而体重只减少60克,如果飞机能用这种效率飞行,那将会节省许多燃料。 鸟类的翅膀具有许多特殊功能和结构,使得它们不仅善于飞行,而且会表演许多“特技”,这些特技还是目前人类的技术难以达到的。小小的蜂鸟是鸟中的“直升机”,它既可以垂直起落,又可以退着飞。在吮吸花蜜时,它不像蜜蜂那样停落在花上,而是悬停于空中。这是多么巧妙的飞行啊。制造具有蜂鸟飞行特性的垂直起落飞机,已经成为许多飞机设计师梦寐以求的愿望。 鹰的眼睛是异常敏锐的。翱翔在两三千米高空的雄鹰,两眼扫视地面,它能够从许多相对运动着的景物中发现兔子、老鼠,并且敏捷地俯冲而下,一举捕获。鹰眼还具有对运动目标敏感、调节迅速等特点,它能准确无误地识别目标。现代电子光学技术的发展,使我们有可能研究一种类似鹰眼的系统,帮助飞行员识别地面目标,同时可以控制导弹。 候鸟的迁徙路程,短则几百公里,长则几千公里。但是,它们总能准确地到达世世代代选定的目的地。这说明候鸟有极好的导航本领。科学家们早已对这些现象展开了研究,认为鸟类所以有很好的导航本领,是因为它们都有各自的特殊感觉器官,能够感觉和分析自然界不同地域环境因素的变化,从而辨认方向,寻找迁徙路线。有的靠辨认太阳的位置,利用太阳作定向标;有的靠辨认星星的方位,利用星象导航;有的靠感觉地球磁场的变化,利用地磁导航;还有的利用地球的重力场导航。弄清鸟类导航的原理之后,仿生学家和设计师就可以模仿制造各种小巧可靠的导航仪器,为发展航空、航海事业做出贡献。 在企鹅的启示下,人们设计了一种新型汽车——“企鹅牌极地越野汽车”。这种汽车用宽阔的底部贴在雪面上,用轮勺推动前进,这样不仅解决了极地运输问题,而且也可以在泥泞地带行驶。 此外,鸟类所特有的生理结构和功能,还为机械系统、仪器设备、建筑结构和工艺流程的创新,提供了许多仿生学上的课题。所以,鸟既是人类的朋友,又是人类的老师。为了科学的未来和人类的幸福,我们也应当好好保护鸟类。 鸟给人类了许多无价的启示:人们看到天空中的飞鸟,想到了一种能把我们带到天空中飞的机器…飞机;山雕飞落地刹那间的坚定和稳重,让人觉得自己也可以从天空中飞下,安全落地;飞翔中的蜻蜓,给人类创造直升飞机带来了灵感;猫头鹰灵巧无声的飞行,改造了飞机的性能;天鹅在水面上撩飞的优雅,使水上飞机问世,。研究金翅鸟能改善飞机功能、研究鸽子可预测地震等那些肯思考的人,通过观察天空中飞行的鸟类,获得了灵感,而创造出来的奇迹,让我们受益无穷 鸟类在自然界的作用 鸟类在自然界的作用系指鸟类在不同生态系统(如森林生态系统,草原生态系统及农田、湖泊、海洋等生态系统)的地位和作用。鸟类是生态系统的重要成员,虽然对生产力可能没有重大影响,但对所食猎物有密度制约作用。此外,鸟类担负着种子及营养物的输送,参与系统内能量流动和无机物质循环,维持生态系统的稳定性。 鸟类捕食昆虫和小型啮齿类动物,在维持自然界生态平衡中的作用并不是直接能感知的,因为所涉及的环境因子十分复杂,必须通过严密的实验设计、繁重的野外调查和实验室工作以及细致的分析,才能得到较为正确的结果。近年国内外有关鸟类捕食作用的定量研究及有关鸟类捕食作用特点的研究,较为恰当地揭示了鸟类在生态系统中的作用,尤其是食虫鸟在森林生态系统中的地位和作用。 一、鸟类的捕食作用 鸟类飞行力强,速度快,活动范围大,而且鸟类的迁徙性,繁殖季节的领域性及繁殖季节后的集群性使鸟类群落结构十分复杂,种类和数量均有很大的波动。鸟类种群的这种集聚及移动可使其数量猛增,并在局部地区“清理”或“消灭”某些猎物。 由于鸟类食量大,代谢速度快,多数食虫鸟类又不像食谷鸟那样具有嗉囔,食物通过消化管的速率也很不相同,与生理需要、取食方式、取食季节、鸟的年龄、鸟的状态及食物本身的性质等都有密切关系。食物消化率的不同,会使在剖胃检查时对某些食物的比率可能估计得过度或过低。为了补偿这些差别,在估计食物组成时要应用校正因子(表1)。要根据虫体残部特征、幼虫头部的被膜、胸及臀部的盾、胸足和腹足残块及上颚残留物来识别种类和数量。 表1 20天幼虫期及15天蛹期内鸟类对5~6龄云杉卷中叶蛾的估计消费量(只/公顷) (自Crawford等,1983) 任何一种鸟类,即使在同一时期,绝不会只以同一种昆虫为食。其食物组成不仅有有害昆虫,也有有益昆虫以及一些已被其它昆早寄生的昆虫,从而增加了分析鸟类对有害昆虫抑制作用的复杂性。然而,最近的一些研究结果表明,鸟类倾向于避开被寄生的昆虫。这样,鸟类与寄生性昆虫可能是互补而不是竞争。还有一些鸟类表现出嗜食某些害虫或虫态,如杜鹃嗜食各种大小的毛虫。某些鸟类喜食成虫,这一点在控制虫害方面很重要,因为成虫阶段的死亡,常对下一世代的种群数量起重要影响 鸟类所食食物有明显的季节性变化。当冬季食物短缺时,许多食虫鸟改吃植物性食物。鸟类生活史的不同阶段中所食食物种类也有变化。雏期阶段,即使是食谷鸟类也必须以昆虫等动物性食物喂养雏鸟,以保证雏鸟正常发育及存活。一般说来,鸟类捕食的食物种类、状态及时期,与自然界能提供的食物资源相一致,这是鸟类与环境之间长期演化适应的结果 鸟类能够影响昆虫种群的数量和动态,同样,昆虫的种类和密度对鸟类的捕食作用也有重要影响。大多数鸟类对猎物种群密度有功能反应和数量反应。前者指当猎物密度增加时,捕食者企图攻击更多的猎物而产生的行为上的变化。后者是由于猎物密度增加致使捕食者在数量上引起的变动。数量上的变化可因繁殖引起,也可因“侵入”而引起。鸟类对昆虫密度的功能反应和数量反应的共同影响可归结为“鸟类对昆虫的直接影响”。鸟类也可以间接影响昆虫种群,这主要是通过改变猎物的微生境,使其对天气、寄生及可能的疾病和病毒更敏感。 查明鸟类的捕食特性以及鸟类与猎物种群的相互作用,对于了解鸟类在生态系统中的地位和作用十分重要。通过鸟类的捕食作用,主要猎物的密度是否被抑制或抑制到何种程度,也是有害昆虫综合治理十分需要的参数。 二、鸟类对森林害虫的控制作用 鸟类对许多森林害虫有重要的捕食作用。限于篇幅,我们仅举一些比较显著的例子,借以说明鸟类对控制各个领域内的森林害虫的作用。 (一)鸟类对食叶性害虫的直接影响 松毛虫(Dendrolimus spp.)是我国主要的食叶性害虫。浙江安吉的调查表明,不同时期和不同地块的鸟类对松毛虫的捕食作用很不相同(表4)。鸟类繁殖季节及林缘,捕食作用可达18.5%和22.2%,而其它地块仅为4.7%。繁殖季节过后,同为林缘,捕食作用下降到8.7%,约为繁殖季节的1/3。在福建漳浦县,食虫鸟对4龄以上松毛虫幼虫的捕食率分别为19.73%(第3代)和48.75%(第4代)。在各种天敌捕食效应中,食虫鸟对松毛虫种群的控制作用最大。通过研究大山雀的生育力、雏鸟食物组成及食物中松毛虫食块的比率,发现随着松毛虫种群密度由高(1985年)到低(1987年),然后又逐渐回升(1988年)的周期性变化,雏鸟食物中松毛虫食块的比率也相应变化(表5),平均窝卵数和窝雏数有不断增加的趋势且繁殖季节开始时间明显提前(表6),表现出明显的功能反应和数量反应。值得注意的是,当松毛虫种群密度低时,尽管大山雀繁殖种群的密度、窝雏数以及雏鸟食中松毛虫食块的比率也相应减少,但捕食作用却比松毛虫种群密度高时增加 11.24倍。 表4 防鸟围网内外松毛虫数量(自楚国忠,1987) 表5 大山雀第一批雏鸟阶段,日平均食物中松毛虫比率 (自楚国忠,1989) 表6 大山雀第一批雏鸟阶段生育力参数的年变化 (自楚国忠,1989) 云杉卷叶蛾(Choristoneura burnijerana)是北美北方云杉- 冷杉森林中最主要的食叶害虫。有人估计在卷叶蛾大发生后的衰落阶段,鸟类约消费13%幼虫。当每公顷卷叶蛾为1235000~2 471 000条时,鸟类的控制程度为5~7%。还有人通过胃容物分析,发现在卷叶蛾大发生条件下,鸟胃食物中40%为卷叶蛾。4年分析结果,卷叶蛾在鸟胃中的比率为7~46%。当卷叶蛾大发生时,鸟类既有功能上的反应也有数量上的反应。原来在地面、树干取食和食草籽的鸟类改变食性,如橙顶灶鸫、草鹀(Junco spp.)、啄木鸟及交嘴雀开始吃卷叶蛾的卵和蛹。几种林莺表现出最大的数量反应,虽然有的林莺数量下降,但栗胸林莺(Dendroica castanea)数量增长12倍,橙胸林莺(D.fusca)9倍。当然,数量大发生时卷叶蛾的密度增加 8000倍。 当松色卷蛾(Choristoneura pinus)发育到4~5龄时,许多鸟类改变食性,开始取食这种丰富的食物,捕食作用发生在老熟幼虫以后,一直到蛹和成虫阶段。第二年,大量乌鸫进入240公顷地块内,当时的松色卷蛾每公顷约24700条,鸟类的捕食作用从第一年的 40~45%增加到第二年的 60~65%。几种山雀取食冬尺蠖(Operophtera brumata)幼虫的数量较低,只有 0.3~2.6%,但取食约10%的羽化的成虫,且主要是雌虫,这样,相当20%的成虫被捕食。在匈牙利,家麻雀和树麻雀可杀死98%以上的成虫,可能对美国白蛾(Hyphantria cunea)起重要控制作用。在日本,树麻雀和灰椋鸟(Sturnus cineraceus)约杀死 40~50%黄昏前出没的美国白蛾,由于这种蛾子的交尾活动发生在日落到日出这段时间,鸟类捕食引起的死亡对该种昆虫的种群动态可能有重要影响。有人在研究山雀和戴菊(Regulus regulus)时发现,大山雀有规律地取食幼林球果小卷蛾幼虫(Ernarmonia conicolana),捕食强度随球果内幼虫密度不同而不同,似乎有一个临界值(每50个球果10只幼虫)。超过此临界值,有利于鸟类捕食。虽然大山雀可能消灭50%以上的越冬老熟幼虫,第二年的种群数量仍然增长。 (二)鸟类对树皮小蠹虫的直接影响和间接影响 啄木鸟是树皮小蠹虫的主要捕食者。主要有毛发啄木鸟(Dendrocopos villosus)、绒啄木鸟(D.pubescens)和三趾啄木鸟(Picoides tridactylus)。它们既表现出功能反应,也表现出数量反应。数量上的反应尤为重要,特别是在局部地区。曾记录到一块火烧过的林地,啄木鸟密度增 加50倍,这种聚集有时在小块林地超过小蠹虫增加的倍数。当红翅小蠹虫(Dendroctonus,ru-fipennis)一般发生时,啄木鸟的取食量为20~29%,由中等密度到高密度时,通过啄木鸟自己取食及其它方式(如树皮干燥)可消灭小蠹虫的24~98%。啄木鸟取食活动可以促进树皮干燥。除啄木鸟外,另有8种鸟类捕食10%的红翅小蠹成虫。啄木鸟捕食瘤额大小蠹(D.frontalis)的数量从5~86%。不同地区报道的结果如此差异,可能是由于气候、暴发程度及过程、每年发生的世代数不同,因而啄木鸟取食活动后所引起的影响也不同。外表树皮啄掉后,剩下的树皮干得快,更容易受到不良气候及疾病的影响,这种死亡率往往比啄木鸟吃掉的还要大。 取食西松大小蠹(D.brevicomis)的鸟类共有4科11种。6种鸟(不包括啄木鸟)捕食成虫,3年中的捕食率在8~26%之间。毛发啄木鸟、绒啄木鸟、北美黑啄木鸟(Dryocopus pileatus)、白头啄木鸟(Picoides albolervatys)是加利福尼亚塞拉中部的西松大小蠹幼虫的最主要捕食者。在大发生的初期,捕食率为32%。在大发生区,啄木鸟种群数量增加。最初是由于迁入,随后则是由于树木死亡增加了啄木鸟巢址和栖居地的可利用性。啄木鸟寻找小蠹虫时,需剥落、刺透或在树皮上凿孔,被啄木鸟剥落的树皮中,有相当数量的小蠹虫卵及约58%的幼虫,它们在冬季都要死亡。啄木鸟啄过后,树皮变薄,温度与湿度都与原来树皮很不相同,减少了树皮对残留小蠹虫的保护作用,也给具短产卵器的寄生者造成产卵机会,所有这些间接影响都增加了小蠹虫的死亡(见图)。 (三)鸟类对蛀干害虫及象鼻虫的直接影响 啄木鸟也是蛀干害虫的主要捕食者。对虎橡天牛(Goes tigrinus)幼虫的捕食率可达32% 及 65%,对山毛榉天牛(G.pulverulentus)幼虫的捕食率可达39%。在两个研究点,对杨黄斑楔天牛(Saperda calcarata)的幼虫捕食率分别为13%和65%。还有人发现,斑啄木鸟食物中98%是山杨楔天牛(Saperda carcharias)幼虫,估计可减少该幼虫的12%。啄木鸟也是紫丁香钻心虫(Podosesia syringae)的最重要天敌,可引起该种虫子 67~81%的死亡。在荷兰,啄木鸟对木蠹象(Pissodes piniphilus)有功能反应和数量反应。木囊象种群数量低时,啄木鸟的捕食量较小,随着木蠹象幼虫数量增加,95%的幼虫和蛹可能被啄木鸟啄食,特别是在食物短缺阶段。但是,树根处的木蠹象往往不能被捕食。 (四)鸟类与昆虫病原物的扩散 已经证明,通过取食被感染的昆虫,鸟类能散布昆虫病原病毒。从树上收集的49堆鸟粪中,44个具有感染性,检测幼虫的89.9%被感染核多角体病毒(NPV)并死亡。鸟类是病毒的被动携带者,冬季时,病毒可至少被扩散到离中心点6km。当然,由于气候及其它条件不同,被吃的感染虫体的鸟粪并不都具有活性。 总之,森林是鸟类的重要生活场所,鸟类和害虫都是森林生态系统的成员,在长期进化和自然选择中形成复杂的捕食者-猎物系统,鸟类是捕食者-猎物系统的重要成分。鸟类的随机捕食性可在生态系统中发挥功能上的控制作用,对许多森林昆虫的种群动态起重要影响。鸟类不仅是害虫的直接死亡因子,还可以通过传播昆虫病原微生物,或者通过改变微生境影响寄生者和捕食者等方式,间接影响害虫种群。当害虫种群密度低或处于密度增加时,鸟类降低害虫数量的作用远较大发生时明显得多。鸟类的主要作用是阻滞或防止害虫大发生,或使大发生的间隔时间加长。但是,单靠鸟类不能使相当范围内大发生的害虫种群瓦解。害虫大发生时,鸟的生殖潜能、取食习性及领域关系减少了它们作为捕食者的影响力。如果害虫发生是小范围的,由于有留鸟的侵入或大群游动鸟的流入,鸟类还可以发挥控制作用,对已达顶峰的害虫种群可加速其衰落。 三、鸟类的其它作用 猛禽(鹰、鸮、隼、雕等)常以森林、草原、农田中的鼠类为食。一些鸦科鸟类和伯劳也能捕食鼠类,它们与其它天敌一道,共同抑制鼠类数量。在结构完整的森林环境中,天敌可抑制和延缓鼠类数量急剧增加,而且还可使数量增加的鼠群密度降低。有人在360只鵟的胃内,共找出1348只老鼠的尸体,有人研究了 19 000块猫头鹰的食物团,发现有46 179只小型兽类,几乎全部是老鼠。对长耳鸮长达5年的食性研究证实,它的主要食物是鼠类,只有1.3%是小鸟。分析湖北武昌越冬长耳鸮的食物残块,发现70.3%是小型鼠类,主要是黑线姬鼠。1982~1986年,在58个乌林鸮(Strix nebulosa)巢中收集 923个食块,其中田鼠(Microtus spp.)和平齿囊鼠(Thomomys talpoides)各占 52%和 29%。 很多鸟类,特别是兀鹰、猫头鹰等猛禽以及海鸥、乌鸦等,都有嗜食腐肉习性。它们在消灭有病的动物和腐烂尸体,消除有机物对环境污染方面有特殊贡献。鸟类可吃掉那些将幼虫寄生在家畜体内外的昆虫,椋鸟和食蜱类鸟可解除危及家畜及野生动物的蜱害及其它寄生虫。 许多鸟类是开花植物的传粉者,尤其是某些热带鸟类,如蜂鸟、花蜜鸟、太阳鸟、啄花鸟、绣眼鸟、鹎、管舌鸟及鹦鹉,常是某些开花乔木和灌木的重要授粉者。没有这些鸟类,自然界的生态平衡可能会被严重扰乱。另外,许多鸟类有储藏种子的行为。松鸦通常将球果藏在叶子、苔藓、石块下,一群松鸦(数量约30~40只)曾收集200 000个松果并带出 1km外。马来半岛低湿林中有7种鸠类取食至少22种榕树果实,绿鸠专食无花果树的种子,通过排粪将种子散布到远方。鸟类散布种子的距离可长可短,许多迁徙鸟类消化道中仍有可存活的种子,它们散布的距离可能稍远些。有人证明,某些硬壳的植物种子通过鸟类消化道后更容易萌发。有些食虫鸟类,如三趾啄木鸟(Picoides spp.)、鸫、山雀和也是重要的散布种子的鸟类。橡树啄木鸟(Melanerpes formicivorus)在各种树上及木质杆上凿洞,并用附近的球果将洞塞满。鸟类所储藏的球果并不都能被它们重新找到,这些被遗忘的果实常是森林扩展的一个原因。

研究昆虫控制的文章Athenix and Monsanto Announce Collaboration on Research for Insect ControlRESEARCH TRIANGLE PARK, NC and ST LOUIS, June 20 /PRNewswire-FirstCall/ -- Athenix C and Monsanto Company today announced they have entered into a three-year research collaboration for insect control on a key class of insects that affects a number of Monsanto's major crops of Financial terms of the agreement were not "We are pleased to work with the market leader in crop genetics to bring our technical capabilities to commercialization," said Mike Koziel, chief executive officer for A "Working with Monsanto to discover novel genes for controlling insect pests increases options for farmers and allows Athenix to demonstrate the power of its integrated discovery platforms for new biotech traits," said Nick Duck, vice president of research at A Athenix will apply its expertise in microbial screening and genomics to facilitate gene discovery intended to help protect crops such as cotton, soybeans and corn against a common class of insects known as H Hemipteran insects include Lygus, a pest of cotton, and stinkbug, a pest of "This collaboration will work to offer an essential benefit to our farmer customers by providing insect protection in crops such as corn, cotton and soybeans against the piercing and sucking Insect tolerant crops allow growers to spray less pesticide, making their operations more efficient and at the same time stewarding the environment," said Robert T Fraley, PD, Monsanto executive vice president and chief technology "We're excited to collaborate with Athenix to help broaden grower's options for insect " About Athenix: Athenix is a leading biotechnology company that develops novel products and technologies for agricultural and industrial applications, including biofuels and Athenix has established an outstanding intellectual property portfolio and market access ability around enhanced plants, microbes, genes, enzymes, and processes with emphasis on two major markets: 1) novel agricultural traits for growers such as insect resistance, nematode resistance, herbicide tolerance, and their use for the crop production industry; and 2) the discovery of genes and proteins for use in the sustainable chemical industry with a focus on biofuels like ethanol and other natural Biological control of locusts New weapons for old enemiesDuring the 1988 desert locust plague, swarms crossed the Atlantic from Mauritania to the Caribbean, flying 5 000 kilometres in 10 Scientists were stumped because migrating swarms normally come down to rest every But locusts can’t swim, so how could it be? It turned out that the swarms were coming down at sea – on any ships they could find, but also in the water The first ones in all drowned but their corpses made rafts for the other ones to rest Since the dawn of agriculture more than 10 000 years ago mankind has had to deal with a resourceful and fearless enemy, Schistocerca gregaria, the desert Normally loners, every so often these natives of the deserts from West Africa to India turn into vast, voracious swarms that leave hunger and poverty behind them wherever they Throughout history, farmers and governments have made attempts to repel the bands and swarms of locusts by collecting insects, creating noise, making smoke and burying and burning the But all of this had little With swarms sometimes extending for hundreds of kilometres, and containing billions of individuals, they conquered by sheer force of Health concernsIt has long puzzled humans where these animals came from and where they Only in the mid-20th century was it realized that the light brown solitary desert-dwelling insect was the same species as the red and yellow locusts of the Only when its biology was understood and chemical pesticides and aerial spraying became available a few decades ago, could efforts be made to control the But large-scale pesticide use also raised real concerns for human health and the On the seventh-floor Emergency Centre for Locust Operations (ECLO) at FAO Headquarters in Rome, Keith Cressman, FAO's locust forecaster, checks current environmental conditions and locust population data from the three computer screens on his The last big locust upsurge ended early in 2005 and the current alert level is green or The experts at FAO’s ECLO are readying to fight the next round in the age-old battle against locusts – wherever and whenever that may “The next time,” says Cressman, “we’ll fight with new tools” New bio-control agents Recent advances in biological control research, coupled with improved surveillance and intelligence, could make a big difference when the next round in the battle is Such products could make it possible to sharply reduce the amount of chemical pesticides One promising avenue is research currently under way at the International Centre for Insect Physiology and Ecology (ICIPE) in N An ICIPE team headed by a Zanzibar-born chemical ecologist, Ahmed Hassanali, has identified and synthesized a specific locust pheromone, or chemical signal, that can be used against young locusts with devastating Phenylacetonitrile, or PAN for short, normally governs swarming behaviour in adult males who also use it to warn other males to leave them in peace while they But, Hassanali found it has startlingly different results on juvenile wingless locusts, known as Hopper bandsJust as adult locusts form swarms, hoppers will, given the right conditions, stop behaving as individuals and line up in marauding bands up to 5 kilometres They are only slightly less voracious than adults, who eat their own weight of food every In three separate field trials – the most recent in Sudan last year – Hassanali’s team showed that even minute doses of PAN could stop hopper bands dead in their tracks and make them break PAN caused the insects to resume solitary Confused and disoriented, some lost their appetite altogether, while others turned cannibal and ate one Any survivors were easy prey for What makes PAN particularly attractive is that the dose needed is only a fraction – typically less than 10 millilitres per hectare – of the quantities of chemical or biological This translates into substantially lower costs – 50 cents per hectare as opposed to US$12 for chemical pesticides and $15-20 for other bio-control That is clearly a major consideration in the countries in the front line – many of them among the world’s Green Muscle A different, but also highly effective biological approach is Green Muscle ®, a bio-pesticide developed by the International Institute for Tropical Agriculture’s biological control centre in Cotonou, Benin, and manufactured in South A Green Muscle ® contains spores of the naturally occurring fungus Metarhizium anisopliae acridum, which germinate on the skin of locusts and penetrate through their The fungus then destroys the locust's tissues from the This is definitely not good news for locusts, but the fungus has no effect on other life A product similar to Green Muscle ® is already successfully used in Australia, but the latter's introduction in Africa and Asia is being slowed by several These include a need for further large-scale trials, official approval of the product in several countries, and a relatively short shelf-life in its normal ready-to-spray liquid One drawback is that it takes days to kill the It is also relatively expensive and large-scale production would need to be A solution would be to store the product in powder form and dilute it just before Hassanali’s team has also shown that, if used in combination with a small amount of PAN, only a quarter of the normal dose of Green Muscle ® is Insect Growth RegulatorsAlso being readied for the modern locust fighter’s armoury is a class of products known as Insect Growth Regulators, or IGRs, which influence the ability of hoppers to moult and grow They have no direct toxic effects on IGRs are effective for several weeks after application and can be used in so-called barrier In this method only narrow swathes of the product are applied, perpendicular to the direction of the marching hopper Only 10 percent of the amount used in blanket treatment is After marching over one or two barriers the hoppers absorb enough product to die while As with PAN and Green Muscle ®, however, IGRs need to be aimed at locusts at an early stage in their lives, before they take to the That, in turn, requires an advanced level of surveillance and intelligence-gathering to make sure that any locust concentrations are nipped in the eLocust2Although back at ECLO Keith Cressman has satellites, computers and mathematical models at his disposal, the weak link in the chain has been the time it takes to get good information from the The mobile ground teams whose job it is to keep tabs on locust populations have to work in some of the world’s remotest, hottest and sometimes (for environmental and security reasons) most hostile A week or more might go by before a report from, say, the central Sahara, reached Cressman’s By that time the locusts – “They don’t need visas,” he says – would quite likely have moved to another country or continent This will soon change Field teams are now being issued with special hand-held devices to record vital locust and environmental data and relay them back to their own headquarters and on to Rome in real Developed by the French Space Agency CNES, the eLocust2 device is able to bounce the information off communications satellites and have the data arrive in the National Locust Control Centre in the affected country a few minutes later, from where they are passed on to Cressman for In case of unusually heavy hopper concentrations, immediate action can be taken to make sure that the locusts never grow old enough to Back to the fieldWriting in Science magazine, locust expert Martin Enserink gave the following graphic description of a locust population gone out of control:“On a beautiful November morning (in Morocco) it’s clear, even from afar, that something’s terribly wrong with the trees around this tiny They are covered with a pinkish-red gloss, as if their leaves were changing "As you get closer, the hue becomes a wriggling mass; a giant cap of insects on every tree, devouring the tiny Get closer still and you’ll hear a soft drizzle: the steady stream of locust droppings falling to the ” Such nightmare visions, and locust plagues with them, may one day be a thing of the

法布尔的《昆虫记》就很好,通俗易懂,生动有趣,蕴含着法布尔几十年来用肉眼发现昆虫世界的所有心血,且由此对生命,生活的感悟和赞美

白蚁,亦称虫尉属节足动物门,昆虫纲,等翅目,类似蚂蚁营社会性生活,其社会阶级为蚁后、蚁王、兵蚁、工蚁。白蚁体软弱而扁,白色、淡黄色、赤褐色或黑褐色均有,各种不同种类体色不一样。口器为典型的咀嚼式,触角念珠状。有长翅、短翅和无翅型。具翅种类有两对狭长膜质翅,翅的大小、形状以及翅脉序均相似,故称等翅目。白蚁的翅经短时间飞行后,能自基部特有的横缝脱落。白蚁属社会性群体生活昆虫,并有复杂的组织分工。在一个群体内的个体,从形态和分工上可分为两大类型,即生殖型和非生殖型。

国内外关于昆虫的期刊

《昆虫分类学报》《应用昆虫学报》

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