基于MaxEnt的西藏飞蝗在中国的适生区预测

西藏飞蝗是青藏高原本地特有物种,为青稞和牧草的重要害虫,近年来危害范围有扩大蔓延趋势。研究并明确西藏飞蝗在中国的适生区域,对制定该虫的早期监测、预警及控制措施意义重大。近年来最大熵理论在物种适生研究领域得到广泛应用,基于西藏飞蝗的分布信息和环境变量,采用MaxEnt生态位模型和ArcGIS对其在中国的潜在分布区进行预测,用ROC曲线检测模型精度、刀切法(jackknife test)筛选主导环境变量及其适宜值。两次模拟的AUC值分别为0.996和0.993,预测结果与实际拟合度很高。西藏飞蝗在中国的高适生区主要位于四川的甘孜州,西藏的昌都地区、林芝地区、山南地区及拉萨市,中适生区则以高适生区为中心向外扩散,集中在青藏高原东部地区。海拔、8月份平均雨量、1月份平均雨量、等温性、12-2月份的平均温度是影响西藏飞蝗潜在分布的主要环境变量。     

Response of Locusta migratoria tibetensis Chen (Orthoptera: Acrididae) to climate warming over the Tibetan plateau

As a region with one of the most important terrestrial ecosystems, the Tibetan plateau is both sensitive to and vulnerable to climate warming. Locusta migratoria tibetensis Chen, an endemic species on the Tibetan plateau, is likely to be affected by climatic warming. In our studies, accumulated degree‐days (ADD) of L. Migratoria T.C. were calculated based on data from 90 weather stations over the Tibetan plateau from 1961 to 2005. Trend lines show that across weather stations, ADD increased at a rate of 1.17 DD/a during climate warming. The majority of weather stations (82.2%) showing increases in ADD were located towards the west of the Tibetan plateau. At higher elevations, the increase in the ratio of annual ADD to the station mean ADD was higher relative to those at lower elevations. A linear regression model between ADD and geographical position was established to create raster maps of ADD in ArcGIS 9.2. The area of potential locust distribution (APD) was estimated to be 42 420 km², mostly distributed along major rivers on the Tibetan plateau. In warmer years, the APD increased sharply over study periods. A new area of potential distribution would appear in the north Tibetan plateau if the climate warming continued. In the south‐east Tibetan plateau, the locust would expand its range northwards or westwards along the river valleys, and the locust APD would also rise in elevation.     

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。     

Characterization and PCR multiplexing of polymorphic microsatellite loci for the locust Locusta migratoria

Because of the scarcity of polymorphic genetic markers available in locust species, only a few population genetics studies have been carried out on this taxon. We isolated and characterized 11 polymorphic microsatellite loci in the pest locust Locusta migratoria capito, and described experimental conditions for polymerase chain reaction (PCR) multiplexing and simultaneously genotyping these loci. The number of alleles per locus ranged from six to 25, and the expected heterozygosity ranged from 0.431 to 0.957. Results of cross‐taxon amplification tests are reported in six other Locusta migratoria subspecies, six species of the Oedipodinae subfamily and two other pest locust species.     

白洋淀蝗虫分布调查及其防治

1998～ 2 0 0 2年对白洋淀蝗区的蝗虫种类、分布、优势种群及蝗区水文、植被、土壤、天敌等进行了调查研究。调查表明 ,白洋淀蝗区有蝗总科昆虫 3 0种 ,隶属 6总科、2 2属 ,分布于白洋淀淀内湖泊蝗区、淀边内涝蝗区和淀外河泛蝗区 ;明确以东亚飞蝗Locustamigratoriamanilensis (Meyen)为主的 5个蝗虫优势种群及生活史 ,并根据不同蝗区类型 ,提出了蝗区治理区划、生态治理技术、应急化学防治等 3项防治技术和“两改一加强”防治手段     

河北省南大港农场2002年夏蝗发生特点及原因浅析

进入 90年代以来 ,南大港蝗区东亚飞蝗Locustamigratoriamanilensis(Meyen)大发生 6次 ,2 0 0 1年夏秋蝗发生面积达 2 6万hm2 ,5龄蝗蝻最高密度为 1 0 0 0 0头 m2 。 2 0 0 2年形势更为严峻 ,仅夏蝗发生面积超过 2万hm2 ;分别造成 1 3 0 0hm2 和 2 70 0hm2 的芦苇被吃成光杆和被啃食的严重破叶。出土时间早、孵化时间长、龄期悬殊大是今年夏蝗发生的主要特点。主要原因是去年越冬卵块基数大 ,其次是受气候条件和农业环境的影响     

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....     

A possible relationship between outbreaks of the oriental migratory locust (Locusta migratoria manilensis Meyen) in China and the El Niño episodes

We investigated the statistical relationship between outbreaks of the oriental migratory locust (Locusta migratoria manilensis Meyen) in the Huang Ho and Huai Ho regions of China and El Niño episodes during 1905–1959, and discussed how El Niño affects locust outbreaks. The outbreaks of the locust mostly occurred 1–2 years after the El Niño episodes. El Niño was suggested to affect the locust outbreaks by changing the precipitation and air temperature in Northern China.     

白洋淀东亚飞蝗持续大发生浅析

进入 90年代以来 ,白洋淀蝗区东亚飞蝗Locustamigratoriamanilensis(Meyen)持续大发生 4次 ,是50年来十分罕见的。究其原因 ,主要受白洋淀水位变化的影响 ,其中 8月水位的高低直接影响翌年夏蝗发生程度 ,其次是生态环境和气候条件等因素的影响。     

Social aggregation of adult Schistocerca gregaria and Locusta migratoria migratorioides in relation to the final moult and ageing

Laboratory experiments, were carried out on nymphs and adults of the desert locust, Schistocerca gregaria, and the African migratory locust, Locusta migratoria migratorioides, in view of the field observation that locusts become temporarily less gregarious after the final moult. The experiments showed no reduction in grouping after the final moult but did show a reduction in grouping in mature Schistocerca. There was little change in the numbers of locusts found in small groups but a dramatic reduction in the number found in large groups.     

The current state of natural foci of swarming locusts (Orthoptera,Acrididae) in Turkmenistan

Climatic changes and anthropogenic impact on natural ecosystems result in the growth of locust populations. The general characteristic of the spatial distribution of the Moroccan (Dociostaurus maroccanus Thunb.), Italian (Calliptamus italicus L.), and Asian migratory (Locusta migratoria migratoria L.) locusts in Turkmenistan are given.     

Oviposition by the African migratory locust, Locusta migratoria migratorioides, in a crop environment in South Africa

Oviposition by the African migratory locust, Locusta migratoria migratorioides (Orthoptera: Acrididae), was studied in maize and wheat crops on the Orange Free State Highveld. Maize was shown to be the most important oviposition habitat with peak laying taking place in autumn and early winter when highest pod densities were recorded. Laying was mainly concentrated along the middle of the crop interrows in maize and within clearings in the wheat crop. Despite the uniform layout of these crops, the distribution of egg pods was found to be aggregated. Non-reproductive behaviour, such as locust aggregation, basking and feeding, as well as environmental factors appeared to influence the distribution of egg pods in these crops. Secondary selection for optinum soil moisture and compaction on the laying site enhanced the aggregation of pods.     

Mass windborne migrations extend the range of the migratory locust in East China

1. Migratory insect pests pose a substantial challenge to global food security. These issues are particularly acute when pest incursions occur considerably beyond the expected range, through natural migration or human‐aided transport, because the lack of species‐specific control strategies and a potential absence of species‐specific natural enemies in the newly‐invaded area may lead to rapid establishment of a new pest.
2. One such threat is posed by the Oriental migratory locust Locusta migratoria manilensis in China, which, historically, has been restricted to eastern China from the Bohai Gulf southwards, and now threatens to expand its range into the agriculturally important region of northeast China.
3. We analyzed data from a recent outbreak of migratory locusts in Heilongjiang Province (extreme northeast China), > 700 km north of its current known range, and identified the source region, timing of arrival and probable migratory routes of this incursion.
4. We further show that warming temperatures in this region will likely allow subsequent invasions to establish permanent populations in northeast China, and thus authorities in this important crop‐producing region of East Asia should be vigilant to the threat posed by this species.

     

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。     

飞蝗及沙漠蝗信息素概述

飞蝗和沙漠蝗自古以来就是重要的农业害虫,这与其生物学特性是密不可分的.信息素对飞蝗和沙漠蝗生物学特征的调节起到了非常重要的作用.到目前为止,沙漠蝗Schistocerca gregaria和飞蝗Locusta migratoria 的研究较为深入,本文对其主要成果进行了综述,以此作为以后飞蝗和沙漠蝗信息素进一步研究的参...     

河北省东亚飞蝗发生动态及未来灾变趋势分析

80年代以来 ,尤其进入 90年代 ,由于受异常气候、农业生态及人为因素的影响 ,河北省东亚飞蝗Locustamigratoriamanilensis (Meyen)出现了暴发频次增加、发生期提前、秋蝗发生加重、潜在和隐伏蝗区突发等特点。作者分析了 5 0年来影响河北省东亚飞蝗发生动态的 5种因素 :气象因素、生态因素、湖库水位因素、河泛流量因素、人为因素等。并对河北省东亚飞蝗未来灾变趋势做了展望。     

西藏飞蝗蝗蝻群集迁移特性及其群集效应

西藏飞蝗Locusta migratoria tibetnsis Chen暴发成灾的重要原因之一是蝗蝻具有群集迁移危害习性。为阐明西藏飞蝗灾变的行为机制,为西藏飞蝗的监测预警和防治提供科学依据,利用视频跟踪技术测定了自然环境中西藏飞蝗蝗蝻群集迁移的运动速度、方向,建立自推进粒子模型模拟蝗蝻群集迁移行为,分析群集迁移效应。结果表明,①不同自然环境中的西藏飞蝗蝗蝻在群集迁移过程中,群体内个体的运动表现出定向集体运动,群集迁移速度为0.1256 m/s,0.2 m以内的个体蝗蝻方向趋向一致。沙滩、翻耕农田和草地蝗蝻群运动一致性参数均较高,分别为0.8502、0.7870和0.6987。②西藏飞蝗蝗蝻群由分散运动转变为群集迁移存在临界密度,密度较低时群体内个体分散运动,当蝗蝻密度达到12-15头/m²时,蝗蝻群体由分散运动转变为高度一致的群集迁移运动。③蝗蝻群通过群集迁移可以显著增加迁移距离,随机运动蝗蝻1 d扩展只有70-80 m,而群集迁移1 d最大距离可达2.5 km。蝗蝻群集迁移可以提高发现特别是远距离食物等资源的概率,使群体中更多的个体受益。④尽管未发现室外蝗蝻群存在先验个体,但模拟发现在群集迁移群体中,只需要少数先验个体（3%-5%）即可引导整个蝗蝻群运动。     

Locust corpora cardiaca contain an inactive adipokinetic hormone

A neuropeptide from the migratory locust, Locusta migratoria, has been identified as a novel member of the family of adipokinetic hormones (AKHs). The peptide is probably synthesised in the brain because it is the first AKH found in the storage lobe, whilst the three 'classic' Locusta AKHs are present in the glandular lobe of the corpora cardiaca. In locusts, the peptide has no biological activity usually associated with AKHs. There is only 36-56% sequence identity with the three Lom-AKHs, but 78% identity with the Drosophila melanogaster AKH, Drm-HrTH. The new peptide is active in the American cockroach, Periplaneta americana, and was provisionally named 'L. migratoria hypertrehalosaemic hormone', Lom-HrTH; its biological role in locusts remains to be established. The high degree of identity with Drm-HrTH suggests that Lom-HrTH is an ancient molecule.     

“Dark cheeks,” a lethal disease of locusts provoked by a lepidopterous baculovirus

The virus causing nuclear polyhedrosis in Spodoptera littoralis (SINPV-type B) could be cross-transmitted perorally to and from two species of locusts, namely the African migratory locust (Locusta migratoria migratorioides) and the desert locust (Schistocerca gregaria). The virus provokes a lethal disease in locusts which was named “dark cheeks.” The progeny viral DNA replicating in the infected locust hoppers was submitted to restriction endonuclease analysis and was found to be identical with the inoculated parental DNA deriving from SINPV-infected S. littoralis caterpillars. Hence the conclusion that an NPV of a lepidopteran host has for the first time been shown to cross-infect and propagate in members of the hemimetabolous order Orthoptera.