散居型西藏飞蝗九个地理种群形态特征的数量分析

为阐明西藏飞蝗Locusta migratoria tibetensis Chen散居型地理种群数量性状的地理变异,将散居型西藏飞蝗9个地理种群雌、雄个体的前翅长度(E)、后足股节长度(F)、头宽(C)、前翅长度与后足股节长度比值(E/F)、后足股节长度与头宽比值(F/C)5项形态特征参数进行系统聚类分析和主成分分析....     

飞蝗的种群遗传学与亚种地位

飞蝗是一种重大农业害虫,其分布范围几乎覆盖了东半球的整个温带和热带地区。由于飞蝗的远距离迁移习性,不同地理种群间的基因交流非常复杂。基于形态学特征,飞蝗曾被建议划分为13个亚种。然而,这些亚种的分类地位一直存有争议,不同亚种或地理种群间的亲缘关系也不十分清楚。近年来飞蝗分子谱系地理学研究的开展,尤其是基于线粒体基因组序列的研究,为飞蝗的种群遗传关系提供了全新的观点。线粒体基因组研究结果表明,飞蝗起源于非洲,通过南北2个主要线路扩散到整个旧世界。分子证据证明世界范围内仅有2个飞蝗亚种,分布于欧亚大陆温带地区的飞蝗属于亚洲飞蝗Locusta migratoria migratoria,分布于非洲、大洋洲和欧亚大陆南部地区的飞蝗属于非洲飞蝗L.m.migratorioides,所有其它的亚种和地理宗都是这2个亚种的地理种群。文中就飞蝗的种群遗传学、亚种分类的研究历史和研究进展进行了综述,还就许多飞蝗地理种群的谱系地理关系进行了讨论。     

飞蝗总DNA的抽提及其RAPD分析条件的摸索

通过试验寻求得到一种快速、简便抽提飞蝗（Ｌocusta sp.)总DNA方法,使每头雄性和雌性成虫分别可以得以５０和１００μg的总ＤＮＡ。所得到的总ＤＮＡ ＯＤ２６０／ＯＤ２８０为１．５－２．２,分子量４５kb。为了获得高分子量的ＤＮＡ产品,使ＲＰＡＤ结果具重复性,酚氯仿抽提后的ＤＮＡ沉淀用灭菌Ｔip头挑出,而不用离心收集。对各种分析条件如摸板、Ｔaq酶、dNTP及引物的浓度、不同的ＰＣＲ仪、反应管进行了比较试验,发现在一定的范围内,它们对ＲＡＰＤ结果影响。用优化的试验条件对我国３个飞蝗亚种５个地理种群进行ＲＡＰＤ分析。结果在３个亚种ＵＰＧＭＡ聚类图中,东亚飞蝗和西藏飞蝗珠２个种群以１００％Ｂootstrap分别聚类在一起,亚洲飞蝗与东亚飞蝗的２个种群以６６％的Ｂootstrap聚类在一起,在３个亚种所有个体的ＵＰＧＭＡ聚类图中,亚种内的所有个体都聚类在一起,各自形成独立分支,说明３个飞蝗亚种有明显的区别。西藏飞蝗的２个种群之间,群居型与散居型东亚飞蝗之间在聚类图中混合聚类,说明它们之间存在基因交流。     

西藏飞蝗九个地理种群群居型形态特征的数量分析

为探讨群居型西藏飞蝗Locusta migratoria tibetensis Chen地理种群数量性状关系,从青藏高原9个地区采集到不同地理种群,以数值分析对形态指标及其比值进行了分析。结果表明,前翅长度(E)、后足股节长度(F)、头宽(C)形态指标和E/F、F/C两个比值可以作为分析种群关系的参数。聚类分析和主成分分析结果相似,能够较好地说明青藏高原9个种群的地理变异和种群相互关系,9个地理种群可以分三个类群,即第Ⅰ类群包括百巴(BB)与八美(BM)种群;第Ⅱ类群包括普兰(PL)、扎囊(ZN)、洛须(LX)种群;第Ⅲ类群包括噶尔(GE)、香孜(XZ)、日土(RT)、那嘎(NG)种群。     

飞蝗新亚种——西藏飞蝗Locusta migratoria tibetensis subsp. n.

一、前言 飞蝗属(Locusta L.)目前在全世界巳知1种莲同本新亚种共7个亚种,即东亚飞蝗(Locusta migratoria manilensis Meyen)、亚洲飞蝗(L.migratoria migratoria L.)、西藏飞蝗(L.migratoria tibetensis subsp.n.)、俄罗斯飞蝗(L.migratoria rossica Uv.et Zolt.)、地中海飞蝗(L.migratoria gallica Rem.)、非洲飞蝗(L.migratoria migratorioides Reiche     

群居型和散居型东亚飞蝗雌成虫飞行肌的超微结构

应用电子显微镜对群居型和散居型东亚飞蝗Locusta migratoria manilensis（Meyen）雌成虫背纵肌进行了比较观察。结果表明：群居型和散居型成虫背纵肌具有类似的亚细胞结构,飞行肌的肌原纤维具有1∶3粗细丝比例,每根粗丝由6根细丝环绕排列成六角形结构。飞行肌的发育和线粒体的形成均是渐进的过程,在不同日龄成虫间存在差异。肌节长度为2.1～3.4 μm;7和10日龄时群居型成虫肌节长度小于散居型;7日龄群居型肌原纤维直径显著大于散居型。背纵肌内线粒体含量约占肌纤维的20%～43%,两型飞蝗之间存在着显著的差异,7日龄时群居型线粒体占肌原纤维的比例高达42.96%,而散居型的只有22.45%;10日龄群居型线粒体含量为41.32%,散居型线粒体29.98%。上述差异可能是东亚飞蝗群居型成虫飞行能力显著强于散居型成虫的重要原因之一。     

中国的飞蝗研究及其治理的主要成就

经实地调查并核对岳阳与九江两地县志后,证明不是终古无蝗,而是很少就地大发生为害。飞蝗Locustamigratoria（L．）是洲际性农业重大害虫。分布于亚排、欧、澳洲。已知有1种10亚种,即亚洲飞蝗Locustamigratoriamigratoria（Linnaeus）、东亚飞蝗L．m.manilensis（Meyen）、西藏飞蝗L．m．tibetensisChen、缅甸飞蝗L．m．bur－manaRamme、非洲飞蝗L．m．migratorioides（Reiche＆Fairmaire）、马达加斯加飞蝗L．m．cap－ito（Saussure）地中海飞蝗L．m．cineracens（Fab-ricius）、西欧飞蝗L．m．gallicaRemaudiere、何氏飞蝗L．m…     

对中国飞蝗种下阶元划分和历史演化过程的几点看法

前人把我国飞蝗划分为东亚飞蝗、亚洲飞蝗和西藏飞蝗三个亚种，并推测我国最原始的飞蝗发生地可能是郑州-开封东北至临清-禹南以南的古黄河冲积扇地带。由于飞蝗的形态、生理、生态等性状受气候与生态条件影响，从而在地区间变化很大，而且过去关于我国飞蝗发生动态和演化的分析均忽视了地史中重大气候事件的影响，因此有关结论的可靠性值得质疑并有待深入验证。根据分子群体遗传学的最新研究结果，我们认为：(1)我国飞蝗应被重新划分为青藏种群、海南种群和北方种群3大类群；(2)我国东部地区(辽宁、黄淮平原、陕西和山西)的飞蝗与海南的飞蝗之间的遗传差别已达亚种水平，因此不是东亚飞蝗，而是亚洲飞蝗经过适应性演化在我国华北地区形成的特异地理宗——华北地理宗；(3)华北地理宗的形成应是末次冰期后种群大规模扩张的结果，推测是由蒙新高原的飞蝗沿黄河流域逐步扩散而来；(4)结合历史上飞蝗发生的情况可以推断，在中国，至少在北至北纬46℃的地区，光周期不会成为飞蝗发育的限制性因素，有效积温可能是惟一限制性气候因子。因此，在气候逐渐变暖的趋势下，飞蝗有逐渐向北扩散的可能，东北地区将会逐步具有飞蝗大发生所需要的必要气候条。     

东亚飞蝗行为和形态型变的判定指标

通过田间、室外罩笼、室内行为测试等一系列实验,研究了东亚飞蝗群居型和散居型之间的行为和形态差异。确立了东亚飞蝗不同生态型个体的形态和行为指标．结果表明,雌雄散居型蝗蝻每分钟的跳跃次数均在1．4以下,转向次数分别在1．3和1．4以下;雌雄群居型蝗蝻每分钟的跳跃次数均在1．6以上,转向次数分别在1．6和1．5以上．群居型蝗虫的跳跃次数、转向次数显著高于散居型蝗虫。所以跳跃次数、转向次数可作为东亚飞蝗行为型变判定指标．在同型不同性别的蝗虫之间行为型变指标没有显著差异．F／C值可作为4龄以上东亚飞蝗的形态型变判定指标。而E／F值可作为东亚飞蝗成虫的形态型变判定指标．两型的F／C值都随龄期的增长而增加,且同龄期雄虫F／C均大于雌虫F／C．F／C、E／F值在不同型态和同型不同性别间均存在极显著差异．因此,确定两型形态型变标准时应将雌、雄虫分开,即雌性和雄性散居型第4、5龄及成虫的F／C值分别大于2．5、2．8、3．3和2．6、2．9、3．5;雌性和雄性群居型第4、5龄及成虫的F／C值分别小于2．5、2．7、3．1和2．5、2．8、3．3．成虫的E／F值也可以作为成蝗形态型变的判断指标．     

分子生态学研究揭示中国飞蝗种群的进化关系

飞蝗是一种重要农业害虫,具有很强的迁飞能力,其分布区比任何其他蝗虫都更广阔,几乎覆盖了东半球的整个温、热带地区。然而,基于生物学或形态学差异,飞蝗仅在中国就鉴定出了3个亚种,而在世界范围内则存在至少9个亚种———这跟其迁飞能力是相矛盾的,学术界对此也一直存留争议。张德兴教授的研究团队（中国科学院动物研究所分子生态学和进化研究组）运用分子生态学的研究手段,从多个独立微卫星DNA位点对覆盖飞蝗中国分布区的25个样点的1300多个标本进行综合分析。他们发现,尽管飞蝗具有很强的迁飞扩散能力,中国的飞蝗确实分为北方种群、南方种群和西藏种群3个具有显著遗传差别的种群,但是与传统认识不同的是,广布于中国中、东部的飞蝗并非东亚飞蝗,而是应隶属于亚洲飞蝗亚种。该研究成果一方面验证了飞蝗经典分类的一些结论,另一方面则指出对由Boris Petrovitch Uvarov（1889~1970）（被学界誉为“蝗虫之父”）在20世纪30年代建立的关于东亚飞蝗的有关权威观点进行修正的必要性。该研究团队还进一步分析飞蝗在中国形成和维持3个具有显著遗传差别的种群的原因,指出：历史生物地理学因素可能是导致形成这3个地理种群的关键原因,特别是更...     

东北地区亚洲飞蝗染色体核型分析

采用常规压片法对吉林省亚洲飞蝗Locusta migratoria migratoria(L.)的染色体核型进行分析.研究结果表明:亚洲飞蝗性别决定机制为X0型,染色体数目为2n♂=23,染色体组式4L+4M+3S+X,全部为端部着丝粒染色体,NF=23.染色体中最长(L1)与最短(S11)染色体之比大于4:1,臂比大...     

菱角萤叶甲不同地理种群数量性状变异(鞘翅目:叶甲科)

采用模糊聚类、系统聚类和主成分分析的方法对中国12个不同地理种群菱角萤叶甲Galerucella birmanica Jacoby的形态数据进行了分析,探讨了其数量性状变异和地理分布间的关系,并对菱角萤叶甲亚种的分类地位进行了界定。聚类分析将我国菱角萤叶甲12个地理种群分为6个部分:其中西南云贵高原地区的保山种群为一组,华南地区的广州种群为一组,东北地区的沈阳种群为一组,华中地区的孝感种群为一组,长江以北地区的淮安、扬州、泰安和阜阳种群为一组,长江以南地区的常州、嘉兴、青浦和义乌种群为一组,可见不同地理种群菱角萤叶甲的数量性状变异与地理分布之间具有显著的相关性。主成分分析显示,菱角萤叶甲各器官的长度存在相互促进共同变异的关系,变异与性状具有显著正相关性。采用形态学测量的方法对于确定菱角萤叶甲亚种的地位是可行的。     

飞蝗研究进展

飞蝗作为农业重大害虫,其分布遍及欧洲、亚洲、非洲和澳洲。全世界共有10个亚种,我国有3个亚种。飞蝗不但分布广,而且数量多、发生频率高,危害极为严重。作者在查阅了国内外近20年文献资料的基础上,结合我国蝗害情况,分别从形态、组织、生理、生化、遗传、毒力及分子系统学等方面综述了国内外飞蝗的研究进展,以期对我国飞蝗的基础及应用研究提供参考。     

Genetic divergence among geographical populations of the migratory locust in China

The random amplified polymorphic DNA (RAPD) technique was used to examine genetic divergence and interrelations of 11 geographical populations of the migratory locust in China, and the role of spatial separation in the population differentiations. AMOVA analysis of genetic variations in all the populations indicated greater within- (79.55%) than among-population variability (20.45%), and that there were significant differentiations among the populations; 11 populations were divided into four regional groups, with significantly greater variability within (82.99%) than among the groups (17.01%), and there existed apparent regional differentiations. Paired comparisons showed significantly greater variability within-than between-groups, indicating significant differentiations between populations of different regional groups. Of all the pairwise comparisons, Hainan and Tibetan groups displayed the greatest differentiation, with the difference between the two groups being seven folds of that between populations within the groups; the least differentiations were exhibited between the groups of Hainan, Xinjiang, and Inner Mongolia, with the differences between groups being only half of the differences between populations within the groups. Mantel tests of the genetic and spatial distances showed that the two matrices were significantly correlated (p<0.01), indicating that the geographical isolation played an important role in the differentiations of the geographical populations of the migratory locusts. Cluster analysis divided all populations into four major groups: Xinjiang and Inner Mongolia group, the Great Plains of North China (the Yellow River and Huai River Plains) group, Hainan group, and Tibet group. Principal component analysis (PCA) supported the division of populations based on the cluster analysis. However, analysis of individuals clustered the locusts into five populations: Xinjiang and Inner Mongolia, Hami in Xinjiang, the Great Plains of North China, Hainan, and Tibet. The locust populations in eastern China displayed apparently continous and gradient variations; as such authors consider that there were no necessity and valid reasons for further division of subspecies. The subspecific status for the main geographical populations of the migratory locusts in China was discussed.     

Genetic divergence among geographical populations of the migratory locust in China

The migratory locust, Locusta migratoria L., which is distributed widely in the East Hemisphere, has long been regarded as the most important agricultural pest and a model insect. Its distribution ranges from thetropic and the subtropical zone, to the temperate zone, and to the cold-temperate zone. Because of the wide geographical distribution and adaptations, many geo- graphical populations of the migratory locust dis- played apparent variation in morphology, life history, physiology, and ot…     

基于细胞色素b基因的中国岩羊不同地理种群遗传差异分析

为了揭示中国岩羊不同地理种群的遗传差异,探讨岩羊亚种分化的分子机制,采用中国岩羊不同地理种群的细胞色素b(Cyt b)基因的全序列,分析了碱基变异情况、遗传距离以及核苷酸序列差异。用最大似然法和贝叶斯法构建分子系统树并对获得的拓扑结构进行分析。结果发现,西藏亚种与四川亚种Cyt b基因平均序列差异为4.2%(±0.007),处于偶蹄目亚种的序列差异范围内,支持了目前对岩羊西藏亚种的分类地位。四川亚种内部各地理种群之间的遗传距离(0.033±0.0 111)与它们分别到西藏种群的遗传距离(0.042±0.007)差异不显著(t=1.824,P=0.084),说明四川亚种内部各地理种群间已经发生较显著的遗传分化。其中,四川、甘肃和青海种群亲缘关系较近,并与四川亚种内部的其它种群已产生了显著的遗传分化。因此认为四川亚种内部各地理种群的种下分化需要深入研究。     

Outbreaks, gene flow and effective population size in the migratory locust, Locusta migratoria: a regional-scale comparative survey

The potential effect of population outbreaks on within and between genetic variation of populations in pest species has rarely been assessed. In this study, we compare patterns of genetic variation in different sets of historically frequently outbreaking and rarely outbreaking populations of an agricultural pest of major importance, the migratory locust, Locusta migratoria . We analyse genetic variation within and between 24 populations at 14 microsatellites in Western Europe, where only ancient and low-intensity outbreaks have been reported (non-outbreaking populations), and in Madagascar and Northern China, where frequent and intense outbreak events have been recorded over the last century (outbreaking populations). Our comparative survey shows that (i) the long-term effective population size is similar in outbreaking and non-outbreaking populations, as evidenced by similar estimates of genetic diversity, and (ii) gene flow is substantially larger among outbreaking populations than among non-outbreaking populations, as evidenced by a fourfold to 30-fold difference in F _ST values. We discuss the implications for population dynamics and the consequences for management strategies of the observed patterns of genetic variation in L. migratoria populations with contrasting historical outbreak frequency and extent.     

HISTORICAL EVIDENCE FOR POPULATION DYNAMICS OF TIBETAN MIGRATORY LOCUST AND THE FORECAST OF ITS OUTBREAK*

Abstract The Tibetan migratory locust (Locusta migratoria tibetensis Chen) is the highest altitude distributed subspecies among the 10 subspecies of migratory locusts. It was discovered and described as new subspecies in 1963. It is mostly distributed above an elevation of 3 000 m, with the highest up to 4 600 m, on the “Roof of the World,” viz. the Qinghai-Xizang Plateau in southwestern China. Recent study on the historic literature revealed ancient records of locust plagues caused by Locusta migratoria tibetensis Chen in many regions of Xizang (Tibet). These disasters took place during 124 years stretching from 1828 to 1952. Forty-five places were infested by locust swarms, and from 1846 to 1857 locust disasters occurred sucessively in 12 years, and affected 18 places of Xizang. At the severe disaster regions crops were damaged by locusts in such a degree that there was no harvest at all. At the same time, locust plagues due to another subspecies also occurred in the plains between the Yellow River and Huaihe and Haihe Rivers in East China. The disasters in Xizang were caused by the Tibetan migratory locust, while in Huang-Huai-Hai Plain disasters were due to the Oriental migratory locust Locusta migratoria manilensis (Meyen). This study not only provides the evidence that the Tibetan migratory locust has been existing as a separate subspecies with a long history, but also reveals the relevant years of locust plagues, their regional distribution and intermittent rules of locust plagues. It also offers a scientific basis for forecasting Tibetan migratory locust disasters and related monitoring strategies; as well as understanding the close relationship between the outbreak of the migratory locust and drought.