云南普洱紫花三叉白及昆虫群落多样性研究

为探究云南普洱紫花三叉白及昆虫群落结构及多样性,掌握昆虫群落多样性发展变化的时空动态,进一步明确紫花三叉白及害虫的种类和发生时间,为害虫防控提供理论参考依据,本研究采用棋盘式取样法,通过定时定点和大范围随机普查的方法,于2016年对云南省普洱市紫花三叉白及标记的样点进行了系统调查。调查期间共调查到节肢动物76种,分属于4纲12目56科。其中植食性节肢动物亚群落46种,分属于34科;捕食类节肢动物亚群落14种,分属于10科;寄生性节肢动物亚群落8种,分属于8科;中性节肢动物亚群落8种,分属于6科。其中科数及物种数最多为双翅目,个体数量最多的为膜翅目。对昆虫群落的多样性指数分析结果表明:双翅目昆虫群落丰富度最高,蜘蛛目优势度指数最高,多样性指数与均匀度均是膜翅目最高。时间上,6月物种数与多样性指数均最大,4月个体数量最多。不同类群分析结果为,植食性节肢动物群落物种数量最多,天敌亚群落的物种数量时间动态相对比较稳定。通过黄板及扫网采集,物种数量的变化趋势与总群落变化趋势基本保持一致,总群落个体数与物种数的变化基本由黄板与扫网采集到的类群主导。通过调查及分析可知,紫花三叉白及节肢动物群落物种数量变化基本由植食类类群主导,节肢动物群落的稳定性较高,天敌亚群落的物种数量时间动态相对比较稳定,非天敌亚群落的群落多样性与个体数量的变化趋势基本一致;物种丰富度与物种均匀度变化趋势基本一致;优势集中性与优势度随时间变化趋势基本一致。进入雨季之后,个体数量有较大幅度的降低,而持续性降雨与暴雨天气是导致个体数量迅速减少的重要因素。     

入闽台湾芒果树冠层节肢动物群落组成结构和多样性

【背景】台湾芒果是我国南方种植的最重要的热带水果之一,其分布广、产量高,极具经济价值。福建地处台湾海峡西岸,与台湾隔海相望,气候条件与台湾相仿,所以台湾芒果很容易在福建定植。然而,台湾芒果在福建的大面积种植,带来了新的虫害问题。因此,掌握台湾芒果园害虫发生的动态及规律对其防治具有重要意义。【方法】2006年8月～2007年8月对福建省惠安县台湾芒果树冠层节肢动物群落进行系统调查。【结果】共采集到28247头节肢动物,隶属于2纲15目79科145种。其中,害虫76种（占总群落物种数的52.[KG-*8]41%）、天敌42种（占28.[KG-*8]97%）、中性昆虫27种（占18.[KG-*8]62%）。芒果园节肢动物的物种丰富度、个体数、群落多样性、均匀性和优势集中性等都呈明显的季节消长规律。多样性指数表现为总群落>天敌亚群落>中性昆虫亚群落>害虫亚群落;均匀度表现为天敌亚群落>中性昆虫亚群落>总群落>害虫亚群落;优势集中性指数表现为害虫亚群落>中性昆虫亚群落>总群落>天敌亚群落。生态优势度测定显示：芒果小爪螨和茶黄蓟马是害虫中的优势种;主要天敌有腹管食螨瓢虫和园蛛科等,优势种是腹管食螨瓢虫;中性昆虫主要以双翅目的花翅摇蚊、啮虫目的凹翅单啮及膜翅目的中国小黑家蚁和红蚂蚁为主。【结论与意义】本研究为芒果园生物资源及天敌的保护与利用、芒果害虫的预测预报和持续控制提供了理论依据。     

入闽台湾芒果树冠层节肢动物群落组成结构和多样性

【背景】台湾芒果是我国南方种植的最重要的热带水果之一,其分布广、产量高,极具经济价值。福建地处台湾海峡西岸,与台湾隔海相望,气候条件与台湾相仿,所以台湾芒果很容易在福建定植。然而,台湾芒果在福建的大面积种植,带来了新的虫害问题。因此,掌握台湾芒果园害虫发生的动态及规律对其防治具有重要意义。【方法】2006年8月～2007年8月对福建省惠安县台湾芒果树冠层节肢动物群落进行系统调查。【结果】共采集到28247头节肢动物,隶属于2纲15目79科145种。其中,害虫76种（占总群落物种数的52.41%）、天敌42种（占28.97%）、中性昆虫27种（占18.62%）。芒果园节肢动物的物种丰富度、个体数、群落多样性、均匀性和优势集中性等都呈明显的季节消长规律。多样性指数表现为总群落〉天敌亚群落〉中性昆虫亚群落〉害虫亚群落;均匀度表现为天敌亚群落〉中性昆虫亚群落〉总群落〉害虫亚群落;优势集中性指数表现为害虫亚群落〉中性昆虫亚群落〉总群落〉天敌亚群落。生态优势度测定显示：芒果小爪螨和茶黄蓟马是害虫中的优势种;主要天敌有腹管食螨瓢虫和园蛛科等,优势种是腹管食螨瓢虫;中性昆虫主要以双翅目的花翅摇蚊、啮虫目的凹翅单啮及膜翅目的中国小黑家蚁和红蚂蚁为主。【结论与意义】本研究为芒果园生物资源及天敌的保护与利用、芒果害虫的预测预报和持续控制提供了理论依据。     

2009-2013年Bt棉田节肢动物群落多样性动态变化

研究多年种植转Bt基因棉花对棉田节肢动物群落昆虫结构与组成、生物多样性的影响,明确其变化趋势,可为棉田害虫综合治理与生态调控、转Bt基因棉花环境安全性评价提供科学借鉴。于2009-2013年连续5年对转Bt基因棉花中棉所41和非转基因棉花中棉所49棉田节肢动物群落进行了系统调查,并结合5a气象因子的变化,分析了5年内棉田节肢动物群落相关参数的变化趋势。结果分析表明,2009-2013年中棉所41棉田昆虫群落、害虫亚群落和天敌亚群落所属目数有所上升,但差异不显著;所属科数、物种数、个体总数均呈现先上升后下降的趋势,个别年份差异显著,其余年份基本保持不显著的波动水平;昆虫群落和害虫亚群落多样性指数呈下降的趋势,至2013年下降达到显著水平,其余年份之间差异不显著,天敌亚群落多样性指数无显著变化;昆虫群落、害虫亚群落和天敌亚群落均匀性指数无显著变化;昆虫群落和害虫亚群落优势集中性指数有所上升,至2013年差异达到显著水平,天敌亚群落优势集中性各年份间无显著变化;与中棉所49棉田相比,相同年份中棉所41棉田昆虫群落、害虫亚群落和天敌亚群落结构与组成、多样性指数、均匀性指数和优势集中性指数均无显著差异。可见,短期内非剧烈天气变化对转基因棉田节肢动物群落、害虫亚群落和天敌亚群落在结构与组成、生物多样性方面没有明显的影响。     

梨园芳香植物间作区节肢动物群落时序格局

以沙地梨园间作罗勒、孔雀草、薄荷为处理,自然生草和清耕区为对照,应用最优分割法和模糊聚类法,探讨梨园节肢动物群落、害虫亚群落和天敌亚群落发生的时序格局特征及其相互联系。结果表明:总群落、害虫亚群落以及其优势种个体数时序变化趋势呈偏态分布,而天敌亚群落以及其优势种个体数的呈正态分布,高峰期出现在6月末至7月中旬,比总群落和害虫亚群落个体数发生高峰晚。在梨树年生长周期的主要时段中,芳香植物间作区较自然生草区、清耕区害虫亚群落的发生数量(4月中至8月底)少;而天敌亚群落发生数量(4月底至6月底)多。梨园各间作区节肢动物总群落和害虫亚群落时序最优格局均可划分5个时段:发展初期、发展期、稳定期、波动期和衰退期;天敌亚群落分为3个时段:发展期、稳定期、衰退期。但处理间在发生时段的时间范围、发生数量及组成特征上存在复杂的差异。梨园节肢动物总群落、害虫亚群落、天敌亚群落时序聚类结果不同,预示着处理间节肢动物总群落、害虫亚群落和天敌亚群落在各发生时段上的个体组成、物种丰富度、群落多样性指数、优势度和均匀度指数存在着差异。     

高山地区甘蓝田节肢动物群落特征

对湖北省高山地区自然天敌控制害虫的甘蓝田的节肢动物群落结构进行了研究.结果表明：自然天敌控制害虫的甘蓝田内害虫优势种为小菜蛾（Plutella xylostella ）、甘蓝蚜（Brevicoryne brassicae）和甘蓝夜蛾（Mamestra brassicae）;天敌优势种为菜蚜茧蜂(Diaeretiella rapae)、菜蛾绒茧蜂（Cotesia plutella）、草间小黑蛛(Erigonidum gramiaicolum)和大灰食蚜蝇（Syrphus corollae）.害虫及天敌亚群落物种的丰富度、多样性、均匀度及集中性在时间序列上有变化;害虫亚群落优势集中性高,优势种突出,群落多样性及均匀性指数较低,天敌亚群落的多样性和均匀性指数较高,优势集中性较低,群落相对比较稳定.经聚类分析,害虫和天敌亚群落的14个时序群落分别被划分为4类和3类.     

吡虫啉对烟田节肢动物群落的影响研究

利用群落参数分析了吡虫啉对烟田节肢动物群落及其各亚群落的影响。结果表明,施药后对烟田节肢动物群落、害虫亚群落的物种数有一定的影响,对天敌昆虫和蜘蛛亚群落物种数的影响不明显。5月23日施药后至6月13日施药区(Ⅱ)和对照区节肢动物群落、害虫亚群落个体数均下降,下降程度施药区大于对照区。6月14日施药后施药区节肢动物群落、害虫亚群落个体数下降,对照区显著上升。两次施药对天敌昆虫和蜘蛛亚群落个体数的影响不明显,施药后一段时间内优势种烟蚜种群个体数量显著下降,使节肢动物群落和害虫亚群落优势集中性下降,多样性指数和稳定性增加。     

三种类型稻田节肢动物群落结构、亚群落内禀增长率与链节数的关系

通过对 3类型稻田 (有机养鸭田、有机稻田和常规化防田 )田间节肢动物群落调查 ,比较了节肢动物总群落丰富度、丰盛度、周转量、3个亚群落 (天敌、中性昆虫、害虫 )调查期间的平均内禀增长力 (r)和通过构建以稻田蜘蛛为顶、中位物种的群落食物网的链节数与害虫、天敌亚群落的 r和链节增长率关系。结果表明 :整个调查期间 ,总群落丰富度呈上升趋势 ,移栽后 72 d前 ,3类稻田总群落丰盛度、丰富度依次为 :有机稻田 >有机养鸭稻田 >常规稻田 ;3类稻田节肢动物群落周转量时间动态均呈上口抛物线趋势 ,其最低值和出现时间依次为 :常规稻田 33.98、74 .1d;有机养鸭田 33.90、79.1d;有机稻田 33.4 9、5 4 .0 d,有机稻田和常规化防田群落周转量和害虫数量呈显著的负相关。 3类稻田中性昆虫亚群落在调查期间的 r依次为 :有机稻田 (0 .0 6 6 5 ) >常规化防田 (0 .0 6 5 2 ) >有机养鸭田 (0 .0 5 0 9) ;天敌 r依次为 :有机稻田 (0 .0 35 2 ) >有机养鸭田 (0 .0 2 4 3) >常规化防田(- 0 .0 132 ) ;害虫的 r依次为 :常规化防田 (0 .0 4 78) >有机养鸭田 (0 .0 199) >有机稻田 (0 .0 198)。 3类稻田总链节数依次为 :有机稻田 (6 6 2 3348) >有机养鸭田 (2 4 982 17) >常规化防田 (136 3372 ) ;每头害虫链节数依     

不同种植环境夏玉米田节肢动物群落特征及稳定性

对云南普洱不同种植环境夏玉米田节肢动物群落进行调查,应用群落特征指数、群落稳定性和主成分分析法,对不同种植环境夏玉米田节肢动物群落特征、稳定性和主成分进行对比分析。结果表明,调查区夏玉米田共采集到节肢动物10174头,隶属2纲15目100科261种,其中单作地夏玉米田采集到节肢动物共计5604头,隶属2纲13目84科168种,混交地夏玉米田采集到节肢动物共计4570头,隶属2纲15目90科209种。与单作地夏玉米田相比,混交地夏玉米田节肢动物群落物种数、多样性指数、均匀性指数、丰富度指数、天敌物种数及个体数均较高;植食性昆虫个体数及其所占比例、优势集中性指数和优势度指数较低;群落较稳定;群落多样性、均匀性、丰富度等指数随时间变化波动较小;单作地夏玉米田中,刺吸昆虫个体数量和食叶昆虫物种数量是主导节肢动物群落变化的最主要因子;混交地夏玉米田中,寄生昆虫个体数量、捕食昆虫物种数量和刺吸昆虫个体数量主导了节肢动物群落的变化。     

生态护理对山地桔园节肢动物群落结构及多样性的影响

采用扫网、目测和手捕的方法,调查了山地桔园生态护理区和常规管理区节肢动物种群结构和多样性,获得生态护理区节肢动物2851只,隶属于2纲11目60科143种,常规管理区节肢动物2311只,隶属于2纲11目50科99种。生态护理区捕食性、寄生性和中性类亚群落节肢动物的种类增加了123.9%～168%,数量增加了83.5%～330.7%;捕食性、寄生性和中性类亚群落优势种群增多,而植食性亚群落相对减少;3—10月各亚群落消长动态相对平稳,害虫优势种柑桔红蜘蛛和桔蚜种群数量一直低于常规管理区,柑桔粉虱则相反;除植食性外,各亚群落的相对丰富度均大于常规管理区、优势集中度均小于常规管理区;总群落、捕食性、中性和植食性亚群落的Shannon指数分别比常规管理区高,而寄生性亚群落则低0.56,Hill多样性指数N1、N2与Shannon指数趋势相似;总群落、中性和植食性亚群落的均匀度指数高0.01～0.21,捕食性和寄生性的低0.03～0.04。因此,生态护理对增加桔园节肢动物种群结构和多样性效果明显,对害虫的持续控制和柑桔安全生产具有实际意义。     

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     

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.     

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.     

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.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

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).     

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.