外来物种褐云玛瑙螺(非洲大蜗牛)

褐云玛瑙螺(Achatina fulica Ferussac,1822),又称非洲大蜗牛．原产于东非沿岸桑给巴尔、奔巴岛一带。据报道,现已知全世界玛瑙螺科Achatinidae共计有23属和亚属,其中玛瑙螺属Achatina有80种和亚种,在我国仅此1种．主要分布于我国福建南部、珠江三角洲、雷州半岛、海南岛、广西南部及云南南部等地区。这一外来物种给当地农业、园艺等经济作物造成很大的危害。     

褐云玛瑙螺螺肉的营养成分分析

本文应用生物化学的方法定量测定了褐云玛瑙螺螺肉的营养成分,分析评价了肉的营养价值。结果表明,它是一种蛋白质含量很高的食用动物。     

褐云玛瑙螺在我国的适生性研究

研究了世界上重要的有害生物－褐云玛瑙螺在我国的适生性。结果表明,该螺的致互最低和最高温度,发育起点温度,世代有效积浊分别为：０．２,４１．２,１２．０℃和２４２２．６日度。在此基础上,综合应用越冬越夏界限,有效积温法则和生物相似距方法,用ＱＵＩＣＫ ＢＡＳＩＣ计算机语言建立了褐云玛瑙螺在我国的适生性区划系统模型。     

褐云玛瑙螺（Achatina fulica）北方冬季室内饲养的探讨

作者在实验室控制温度、湿度等条件下,以麦麸、玉米面粉及鸭跖草为饲料对褐云玛瑙螺进行室内饲养。实验表明：在温度２６℃,相对湿度８０￣９０％的条件下,每个成螺平均产卵２３４．４粒;卵孵化率为９０．７２％;幼螺成活率为９４．３％;从初孵幼螺长至体重为３５．６ｇ的成螺需１９６天／２６℃,１７３天／２８℃;从２克重的幼螺长至３５．６克重的成螺,每个螺平均累积取食混合饲料２２９．７ｇ。饲养密度会影响螺的生长,     

基于入侵植物和蜗牛信息素的非洲大蜗牛新型诱杀剂研究

[目的]非洲大蜗牛是被世界自然保护联盟列入黑名单的一种入侵陆生螺。目前，其主要防治手段是使用化学农药，但化学农药有危害生态环境、威胁生物多样性的副作用。本研究旨在针对化学防治污染生态环境等问题，开发非洲大蜗牛新型植物源诱杀剂。[方法]通过对非洲大蜗牛的诱食、灭杀和诱杀试验测定，对比入侵植物提取物和非洲大蜗牛腹足部腺体中的信息素提取物复配成的诱杀剂对非洲大蜗牛的诱杀效果。[结果]食物诱食试验结果发现，非洲大蜗牛腹足部腺体中的信息素选择比例为40.30%，偏好性明显高于氨基酸、含硫化合物甜菜碱和酵母等。以五爪金龙和薇甘菊2种入侵植物提取物复配成的杀螺剂处理后，在24、48 h时非洲大蜗牛的死亡率分别达到65%、100%。利用信息素为诱剂，结合具有高效毒杀作用的入侵植物(五爪金龙和薇甘菊)粗提物复配成的诱杀剂，引诱率为34.12%，仅次于未复配的信息素(37.45%)，而诱杀率明显优于所选择的市售诱杀药物。[结论]以入侵植物五爪金龙和薇甘菊为杀螺剂原料结合非洲大蜗牛诱食信息素，复配制成的诱杀剂(诱杀率31.76%)见效快、杀灭效果强，并且安全环保，减少了农药对生态环境的危害。     

褐云玛瑙螺（Achatina fulica）胚胎发育不同时间酯酶同工酶分析

采用聚丙烯酰胺凝胶电泳法,分析了褐云玛瑙螺胚胎发育不同时间的酯酶（ＥＳＴ）同工酶。实验结果表明,在２５℃控温条件下胚胎发育早期ＥＳＴ同工酶谱带显示较弱;到初孵幼螺前的整个发育阶段的ＥＳＴ同工酶谱带呈逐渐递增趋势;初孵幼螺ＥＳＴ同工酶谱带增多。两种不同温度（在３０℃控温条件下进行了胚胎发育三个不同时间的ＥＳＴ同工酶分析）下胚胎发育至８小时的ＥＳＴ 同工酶谱带差异显著。初孵幼螺前２４小时的胚胎发育ＥＳ     

海口市外来入侵植物现状及防控对策

基于野外调查及文献资料及标本信息查阅,基本查清海口市外来入侵植物的种类组成、原产地、生活型、入侵途径,并对外来入侵植物在海口市的入侵危害进行等级划分。结果表明,海口市目前发现外来入侵植物115种,隶属于32科83属,其中菊科种数最多,有23种,占海口外来入侵植物总种数的20.0%;有92种原产地为美洲,占80.0%;有84种为草本植物,占73.0%;有111种为人类有意或无意引入,占96.5%;入侵植物中严重危害类(1级)有12种,一般危害类(2级)有24种,潜在危害类(3级)有25种,一般外来类(4级)有22种,32种还有待观察(5级)。文中提出对海口外来植物入侵的防控及管理对策。     

入侵植物筛选方法在我国口岸防控中的应用建议

入侵植物是生物入侵中数量最多的类群,给全世界造成了重大的经济和环境影响。植物入侵的预测研究是口岸防控工作中的重要技术环节之一。本文介绍了入侵植物筛选方法的概念,简述了与之相关的基础理论、研究情况以及3种植物入侵的预测方法。综合来看,入侵植物筛选方法主要采用植物自身的生物生态学特性作为评估指标来筛选外来植物,能快速可靠地将外来植物评判为严重入侵植物、非入侵植物以及介于二者之间的一般入侵植物,因此该方法能为我国口岸防范外来植物入侵的管理提供基础技术支撑。当前我国入侵植物筛选方法的研究和应用尚处起步阶段,通过本文的简述期望引起相关人员对此问题进行探讨,并为我国口岸入侵植物防控工作提供理论参考。     

我国对3种外来入侵植物的利用

主要介绍了我国在防治生物入侵时,对水葫芦、紫茎泽兰、互花米草等入侵植物的综合利用.     

植物外来种入侵及其对生态系统的影响

对植物外来种的入侵及生态系统的影响进行综述与分析,植物入侵多种因子的影响,可分为外因和内因两类,植物外来种对生态系统的影响主要体现在生产力,土壤营养,水分,干扰体制,群落的结构和动态等方面,在管理外来种时,需对外来种的特性和影响因子进行系统的观察研究,采用机械法,化学方法和生物控制法等综合办法控制植物的入侵,引进植物引来种时,要对引进种的行为特性进行了调查研究,注意其安全性。     

Purification and characterization of an agglutinin from mucus of the snail Achatina fulica

The mucus of the snail Achatina fulica shows the presence of an agglutinin that nonspecifically agglutinates human erythrocytes. The agglutinin has been purified by affinity chromatography using Sepharose 4B-hog gastric mucin as the affinity matrix. Homogeneity was checked by polyacrylamide gel electrophoresis, immunodiffusion, immunoelectrophoresis, and gel filtration. The agglutinin is a glycoprotein of native molecular weight 70,000. The isoelectric point of the protein was found to be 8.0. The predominant amino acids are aspartic acid and glutamic acid (or amides) and serine, which account for 32% of the total amino acid residues. The agglutinin has 10% carbohydrate (wt/wt) and the most abundant sugar is N-acetylglucosamine. The cd spectra of the agglutinin show the presence of random coil conformation. The inhibition of hemagglutination data indicates that the agglutinin is specific for beta glycosides of D-Gal and D-GalNAc.     

Localization and characterization of acharan sulfate in the body of the giant African snail Achatina fulica

Acharan sulfate is a glycosaminoglycan (GAG), having the structure →4)-2-acetamido-2-deoxy-α- -glucopyranose(1→4)-2-sulfo-α- -idopyranosyluronic acid (1→, isolated from the body of the giant African snail Achatina fulica. This GAG represents 3–5% of the dry weight of this snail's soft body tissues. Frozen sections and polyester wax sections of the snail's body were stained by Alcian blue-periodic acid-Schiff's reagent (PAS) to localize acharan sulfate. Alcian blue staining indicated that GAG was mainly secreted into the outer surface of the body from internal granules. A highly mucous material was collected and treated and the acharan sulfate was recovered by ethanol and cetyl pyridinium chloride precipitation. Crude acharan sulfate was purified by DEAE-Sephacel ion-exchange chromatography. Depolymerization of intact mucus and purified acharan sulfate fractions by heparin lyase II (heparitinase I) from Flavobacterium heparinum produced an unsaturated disaccharide as a major product, establishing the repeating unit of acharan sulfate. These results demonstrate that mucus in the granule and secreted to the outside of the body is composed entirely of acharan sulfate.     

二疣犀甲对油棕、椰子的风险性分析及防控策略

二疣犀甲是危害椰子、油棕等木本油料作物的重要害虫,本文从形态学、生物学、分布及危害等不同方面对该虫进行了阐述,并对其风险性进行了定性定量评价,结果表明:二疣犀甲的R值为2.0,属于高风险有害生物。同时从生物防治、物理防治、化学防治、农事操作及检验检疫技术的应用等方面制定了二疣犀甲的综合防控策略,为该虫的危害评价和防护技术的制定提供了参考。     

外来植物肿柄菊对入侵生境的生态影响及其防控对策

入侵杂草肿柄菊对我国热带和亚热带地区的生物多样性和生态系统功能产生严重影响,且其入侵呈现快速扩张态势。为提高对肿柄菊入侵危害的认识水平,加强对肿柄菊的监测预警及防控,本文通过搜集、整理和分析相关文献资料,总结肿柄菊在世界各国不同地区的入侵情况及其影响,分析肿柄菊在我国入侵的历史、分布现状及其入侵对遗传多样性、物种多样性和生态系统多样性的影响。结合肿柄菊生态入侵防控研究与应用实践,指出肿柄菊入侵防控存在的主要问题和面临的挑战,并针对肿柄菊监测和高效防控技术体系提出高度重视肿柄菊入侵危害影响的分类风险评价、多元化开展肿柄菊入侵扩张的基础科学研究、建立早监测早预防的预警机制和构建针对肿柄菊入侵防控的综合技术体系等防控对策。     

云南省林地薇甘菊防控研究进展

薇甘菊是世界十大有害杂草之一,引起广泛关注,因其入侵能力强,给入侵地的生态系统造成了极大威胁。本文系统总结云南省林地薇甘菊防治研究进展:开发出"林地薇甘菊监测预警信息系统"和"薇甘菊风险评估管理信息系统",提高了薇甘菊在云南省潜在分布区域预测的可靠性;筛选及复配出林地防效好的森草净+2,4-D钠盐,对土壤相对较为安全的2,4-D+敌草快复合药剂;选用旱冬瓜、千果榄仁、柱花草等替代控制薇甘菊,防控的同时还能创造更大的经济效益;发现薇甘菊颈盲蝽是控制薇甘菊的专化性强且取食量大的重要天敌昆虫,实现了对薇甘菊种子扩散和无性传播的有效控制。对薇甘菊的防治,集成了监测预警、应急除治、生物防治、生态修复技术,形成林地薇甘菊绿色防控技术体系,但其防控仍是局部的,未来还需要不断突破,使对薇甘菊的局部应急防控逐步转为大面积的持续生态控制。     

Stromata, sporangiomata and chlamydosori of Phytophthora ramorum on inoculated Mediterranean woody plants

Three types of multihyphal structures, stromata, sporangiomata and chlamydosori, are described for the plant pathogen Phytophthora ramorum. Their morphology, morphogenesis and position on the host organ were observed by dissecting, compound and scanning electron microscopy. Stromata were consistently formed one to two weeks after zoospore inoculation of detached leaves and fruits of an assortment of Mediterranean sclerophyll shrubs. Stroma initials appeared subcuticularly or subepidermally and developed as small hyphal aggregates by repeated branching, budding, swelling and interweaving, eventually forming a prosenchyma. They always emerged through the adaxial side of the leaf by rupture of the overlying host tissue. Occasionally sporangia and chlamydosori (packed clusters of chlamydospores) were formed on the stromata. Sporangiomata bore short sporangiophores and clusters of 20–100 sporangia and resembled sporodochia of the mitosporic fungi. The biological significance of these multihyphal structures is discussed. Some epidemiological aspects were also studied: several understorey species of the holm oak (Quercus ilex) woodland were susceptible to in vitro infection with three isolates of P. ramorum originally collected from different ornamental hosts. The risk of spread to this ecosystem is evaluated.     

Life-history of predatory mites Neoseiulus californicus and Phytoseiulus persimilis (Acari: Phytoseiidae) on four spider mite species as prey, with special reference to Tetranychus evansi (Acari: Tetranychidae)

The commercially available strains of Phytoseiulus persimilis Athias-Henriot, the biological control agent of Tetranychus urticae Koch, perform poorly in the Western Mediterranean, probably because they are not well adapted to local climatic conditions. For that reason, efforts are being focused on the development of a biological control programme using native phytoseiid mites. Four species of red spider mites can be found in vegetable crops in eastern Spain: T. urticae, Tetranychus turkestani Ugarov and Nikolski, Tetranychus ludeni Zacher and the recently introduced Tetranychus evansi Baker and Pritchard. To evaluate their potential role as biological control agents, the present study evaluates the life-history of local populations of Neoseiulus californicus (McGregor) and P. persimilis when fed on T. urticae, T. turkestani, T. evansi, and T. ludeni in the laboratory. Results indicate that N. californicus and P. persimilis are able to feed and complete their development on the four tested red spider mite species. The predators may exhibit a particularly high capacity for population increase when fed on T. urticae, T. turkestani, and T. ludeni, thus may be able to provide effective control of these species in the field. When fed T. evansi, however, predator performance was poor; significant increase in development and preoviposition times, and a reduction in oviposition period and fecundity were recorded. The resultant low capacity for population growth suggests poor ability of the two tested predators to suppress T. evansi populations on commercial crops. It is unlikely therefore that P. persimilis and N. californicus, now being widely used to control T. urticae in greenhouse crops in Central Europe, will be able to halt any spread of T. evansi to greenhouse crops in temperate areas.     

入侵植物马缨丹研究进展

马缨丹原产于热带美洲,现已扩散至世界热带和亚热带地区,并严重威胁入侵地本地植物的生长。马缨丹因具有观赏价值而被我国大量引进,但由于疏于管理,发展成为入侵杂草,对我国农业、畜牧业及生态环境造成严重危害。目前对马缨丹的入侵机制还没有全面系统的认识。本文从马缨丹的生物学特性、入侵机制、生态学效应、防治与应用等方面进行综述,总结其研究进展,以期为马缨丹的防治工作提供依据。研究结果显示:马缨丹成功入侵的关键因素源于其独特的生物学性征;对农林业造成的危害的原因主要为它的化感作用;马缨丹的防治方法主要包括物理、化学和生物防治;马缨丹在防虫除虫、污染修复、药用价值等方面有所应用。此外,分析当前研究中的不足后发现,今后应加强马缨丹在自然环境中的适应机制、应用潜力、防治方法等的研究。     

Evaluating the impact of a biological control parasitoid on invasive Vespula wasps in a natural forest ecosystem

The overall impact of the parasitoid Sphecophaga vesparum vesparum on invasive Vespula wasps in New Zealand native beech forest was evaluated by assessing the levels of parasitism achieved and the parasitoid’s effect at nest level and population level. The maximum proportion of nests parasitised was 17%, but there was no significant increase with time (r² = 0.139; p = 0.115). However, there was an exponential reduction in the number of parasitoids produced per parasitised nest from a peak of 570 (SE = 143) parasitoids per nest in 1990, declining to only 15 (SE = 6) parasitoids per nest in 2004. Even when parasitoid density was high, the parasitoid had no detectable impact on the number of small cells or the total host nest size, but it halved the number of large (reproductive) cells produced. This may have resulted in fewer queens produced per parasitised nest. Wasp nest density was highly variable from year to year, but there was no evidence that the wasp population density at the parasitised site (Pelorus Bridge) had declined relative to the five sites where the parasitoid had not established. We conclude that the parasitoid is unlikely to have had any significant effect on wasp populations hitherto, nor is it likely to impact host populations in the future. We recommend other biological control programs adopt pre-release assessment of per capita impact as a way of identifying agents that are more likely to be successful and hence minimising economic and potential ecological costs of biocontrol.