进境熊蜂风险分析

【目的】对进境熊蜂所带来的病虫害、生物入侵等一系列风险进行分析,为制定相应的检疫措施提供科学依据。【方法】本文根据新西兰风险分析模型,从传入释放的可能性、定殖和扩散的可能性以及对经济和生态的潜在危害性3个方面对进境熊蜂进行风险分析。【结果】熊蜂孢子虫Apicystis bombi、熊蜂短膜虫Crithidia bombi、熊蜂微孢子虫Nosema bombi、布赫纳蝗螨Locustacurus buchneri、寄生蜂Melittobia acasta和蜂巢小甲虫Aethina tumida 6种病虫害能给国内熊蜂带来较高的风险,同时引进非本地种熊蜂也可能带来生物入侵问题。【结论】进境熊蜂能带来一定的风险,需要制定相应的风险管理措施。     

应用PCR技术快速检测熊蜂短膜虫

【目的】近年来,熊蜂作为温室作物的理想授粉者在国外已被广泛利用,并且获得很好的经济效益和生态效益,所以国外熊蜂经常被进口用于设施农业。熊蜂短膜虫Crithidia bombi是熊蜂的一种重要寄生虫病,一旦随进口熊蜂传入,将给国内熊蜂蜂群带来严重危害,因此迫切需要建立一种熊蜂短膜虫检测方法。【方法】基于熊蜂短膜虫基因内转录间隔区(internal transcribed space,ITS)基因序列设计了一对引物(Cri-F/R),建立了熊蜂短膜虫的PCR检测方法,并对退火温度、引物浓度和循环个数等反应条件进行了优化,同时验证了该PCR方法的灵敏性、特异性和稳定性。【结果】以熊蜂短膜虫ITS基因保守区设计特异性引物建立的熊蜂短膜虫PCR检测方法是可行的。优化的PCR反应条件为:退火温度59℃,引物浓度0.5μmol/L,扩增循环数35次。对感染熊蜂短膜虫的熊蜂总DNA的灵敏度达到13.24×10-5ng/μL,并具有良好的特异性和稳定性。将该方法应用于熊蜂短膜虫的检测,整个检测过程不超过4 h,具有良好的适用性。【结论】研究建立了熊蜂短膜虫检测方法,能用于疫情监测和进境熊蜂的检验检疫。     

欧洲地熊蜂对我国本土熊蜂的生殖干扰评估

【目的】外来物种与本土亲缘关系较近的物种可能会发生交尾竞争,干扰本土物种的正常繁衍。欧洲地熊蜂Bombus terrestris是全球范围内商业化应用最广的传粉蜂种,但在许多国家造成了生物入侵。本研究旨在明确欧洲地熊蜂对我国本土熊蜂产生生殖干扰的可能性。【方法】采用四级杆飞行时间-气质联用系统(gas chromatography-quadrupole time of flight mass spectrometry,GC-QTOF/MS)测定了欧洲地熊蜂和我国本土9种熊蜂的雄蜂头部分泌物的成分,并进行聚类分析;在人工控制环境下比较了欧洲地熊蜂对我国重要熊蜂种类的交尾影响。【结果】雄蜂头部分泌物气质色谱图在同一熊蜂种内基本一致,而在不同熊蜂种之间差异明显;我国红光熊蜂B.ignitus、兰州熊蜂B.lantschouensis与欧洲地熊蜂的雄蜂头部分泌物成分相似性分别为58.49%与49.23%;在人工控制环境下欧洲地熊蜂雄蜂可以与兰州熊蜂蜂王杂交,并能够显著降低兰州熊蜂的交尾成功率(P0.01)。【结论】欧洲地熊蜂与我国一些熊蜂种的雄蜂头部分泌物成分相似性较高,能够干扰其正常交尾,具有较高的生殖干扰风险。为了保护我国本土熊蜂资源与生态系统平衡避免造成生物入侵,我们应该谨慎使用外来熊蜂物种。     

进境蜜蜂疫病传入风险分析

为有效防范疫病传入,保护国内生态和环境安全,本文根据新西兰风险分析模型,从传入释放的可能性、定殖和扩散的可能性以及对经济和生态的潜在危害性3个方面对进境蜜蜂所可能携带的病毒、细菌、真菌、寄生物和敌害等危害进行风险分析。结果表明,蜂群崩溃失调病Colony Collapse Disorder、美洲幼虫腐臭病American Foulbrood、欧洲幼虫腐臭病European Foulbrood、武氏蜂盾螨Acrapis woodi、小蜂螨Tropilaelaps spp.、狄斯瓦螨Varroa destructor、蚤蝇Apocephalus borealis和蜂巢小甲虫Small Hive Beetle(Aethina tumida Murray,SHB)等8种病虫害能给国内蜜蜂带来一定的风险,根据风险评估结果,提出了相应的风险管理措施。研究结果能为制定相应的检疫措施提供科学依据。     

短舌熊蜂耐热性研究

【目的】测定高温对短舌熊蜂Bombus terrestris L.个体存活率和体内总蛋白含量的影响,为熊蜂授粉应用提供理论依据。【方法】以高温暴露致死率为耐热性的评价指标,对短舌熊蜂的工蜂幼虫,成年工蜂,成年雄蜂进行检测并对成年工蜂进行亚致死高温驯化。同时考察不同处理温度下熊蜂体内蛋白质含量变化。【结果】结果显示,短舌熊蜂的耐热性能从高到低依次是成年工蜂、成年雄蜂、工蜂幼虫,亚致死高温驯化可显著提高成年工蜂的耐热性能。熊蜂体内蛋白质含量随着温度的升高,呈先增加后减少的趋势,熊蜂体重与体内蛋白质含量无显著相关性。【结论】熊蜂不同虫态对高温的耐受性不同,可通过亚致死高温驯化措施来提高熊蜂的耐热性能和授粉效率。     

台州口岸进境近海小型国际航行船舶携带有害生物疫情调查

【目的】国际航行船舶可携带多种植物疫情,造成有害生物入侵。分析进境近海小型国际航行船舶携带有害生物疫情,能够为对该类船舶开展针对性检疫查验提供依据。【方法】对台州口岸进境小型国际航行船舶的概况、食品舱卫生状况和携带有害生物种类、来源进行调查和数据分析。【结果】2015—2016年调查了3193艘次船舶,共截获有害生物686种次,其中87.5%是昆虫类,截获比例最高时期为6—8月,55.9%的有害生物在干货类食品中截获,食品舱卫生差的船舶中有害生物检出比率为36.1%。【结论】进境近海小型国际航行携带有害生物情况严重,有害生物的发生具明显的季节性,食品舱卫生状况与有害生物携带风险密切相关,应采取有效的检疫措施。     

熊蜂主要病虫害的发生和危害现状

熊蜂以其独有的形态特征与生物学特性,在植物授粉中发挥着十分重要作用.然而受寄生虫、真菌等多种病原体影响,近几十年来全球多个地区熊蜂多样性急剧下降.欧洲地熊蜂Bombus terrestris在全球商业化推广应用,加剧了相关熊蜂病虫害的传播和蔓延,已在多地造成生物入侵危害,导致当地传粉蜂多样性下降.本文综述了熊蜂主要病虫害的种类、危害和传播情况,以期有全面深入的认识,并提出对进口商业化熊蜂的管理措施,为我国本土熊蜂资源保护研究奠定基础.     

11种常用农药对地熊蜂工蜂的毒性和风险评估

【目的】评估常用农药对地熊蜂Bombus terrestris的生态风险,为设施大棚合理施用农药提供科学依据。【方法】分别采用饲喂法和接触法测定了6种杀虫剂(虫螨腈、高效氯氟氰菊酯、氟吡呋喃酮、螺虫乙酯、异丙威和除虫脲)、3种杀螨剂(丁氟螨酯、唑螨酯和联苯肼酯)及2种杀菌剂(春雷霉素和啶酰菌胺)共11种常用农药对地熊蜂成年工蜂的急性经口和急性接触毒性,并评估其生态风险性。【结果】11种农药经饲喂法测定,对地熊蜂工蜂的急性经口毒性除高效氯氟氰菊酯、异丙威和虫螨腈为高毒,氟吡呋喃酮和唑螨酯为中毒外,其余药物均为低毒。经接触法测定,对地熊工蜂的急性接触毒性除高效氯氟氰菊酯和异丙威为高毒,虫螨腈为中毒外,其余药物均为低毒。生态风险评估表明,对地熊蜂工蜂而言,异丙威和高效氯氟氰菊酯的经口与接触毒性为中风险,氟吡呋喃酮、啶酰菌胺、除虫脲、唑螨酯、联苯肼酯、螺虫乙酯、春雷霉素、丁氟螨酯的经口与接触毒性为低风险;虫螨腈的经口毒性为中风险,接触毒性为低风险。【结论】在设施作物花期使用地熊蜂授粉时,建议禁用异丙威、高效氯氟氰菊酯和虫螨腈这3种存在中风险的农药,慎重使用氟吡呋喃酮和唑螨酯这2种农药,以避免对地熊蜂造成危害,而另外6种低毒农药可根据田间情况合理施用,并可采取通风晾晒、设置间隔期等方式降低农药对地熊蜂的生态风险。     

惠州口岸进境粮谷外来杂草调查与监测

【目的】随着国际农产品贸易的发展,外来杂草入侵我国的形势越来越严峻。对惠州口岸进境粮谷外来杂草进行调查与监测,能够为惠州口岸进境粮谷检疫监管工作提供参考。【方法】通过实地调查、监测,对惠州口岸进境粮谷厂区及周边外来入侵杂草的种类组成、分布、生活型、原产地、入侵途径和危害程度进行了分析。【结果】惠州口岸进境粮谷厂区及周边外来杂草有12科28种,其中,检疫性杂草有4种。在外来入侵杂草中,菊科植物种类最多,生活型以一年生草本为主;原产地以美洲为主,主要以无意引入,有7种杂草较严重危害当地生态环境。【结论】首次调查和总结了惠州口岸进境粮谷厂区及周边外来入侵杂草的名单和类别,提出了外来杂草口岸防控的建议。     

中国明亮熊蜂复合种的分子鉴定及分布特性

【目的】为了探明中国境内明亮熊蜂复合种Bombus lucorum complex的物种组成及其分布特性。【方法】利用DNA条形码技术对来源于中国境内的明亮熊蜂复合种的223个标本进行了鉴定, 并根据鉴定结果分析了各物种的分布特性。【结果】中国境内明亮熊蜂复合种包括地熊蜂B. terrestris、 隐熊蜂B. cryptarum、 明亮熊蜂B. lucorum和长翅熊蜂B. longipennis。4种熊蜂共获得160条DNA条形码序列, 包含36个单倍型, 其中B. longipennis单倍型最多, 为14个; B. terrestris最少, 为3个。B. terrestris和B. lucorum亲缘关系最远, 其遗传距离为0.077; B. lucorum和B. longipennis亲缘关系最近, 其遗传距离为0.034。系统进化分析（贝叶斯法和最大似然法）表明, 4种熊蜂的分化先后顺序为B. terrestris, B. longipennis, B. lucorum和B. cryptarum。4种熊蜂的分布格局不同, 平均分布海拔高度由高到低的顺序依次为B. longipennis, B. cryptarum, B. lucorum和B. terrestris。B. longipennis发现于高海拔的青藏高原东部及南部地区, 而B. terrestris仅发现于低海拔的新疆西北部边界地带。【结论】本研究探明了中国境内明亮熊蜂复合种的分类地位及其分布特性, 为深入研究该类群的资源保护和农业授粉利用奠定了基础。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.