Role of ants in structuring the aphid community on apple

1. The aphids Dysaphis plantaginea Passerini, Aphis spp. (Aphis pomi De Geer and Aphis spiraecola Patch), and Eriosoma lanigerum Hausmann are commonly found together in apple orchards. Ants establish a mutualistic relationship with the myrmecophilous aphids D. plantaginea and Aphis spp. but not with E. lanigerum. 2. Field surveys and one experiment manipulating the presence of ants and the aphid species were conducted to test the hypothesis that ants play a role in structuring the community of these aphids on apple. 3. Ants tended D. plantaginea and Aphis spp. but not E. lanigerum colonies. In the field, D. plantaginea performed better in the presence of ants while no effect was observed in Aphis spp. Contrarily, populations of Aphis spp. in the manipulative experiment performed better in the presence of ants while no differences were observed for D. plantaginea. Such differences between field and manipulative conditions could be related to thermal tolerance, phenology, and life cycles. In contrast, populations of E. lanigerum were reduced in the presence of ants. 4. Ants also had a significant negative effect on the abundance of natural enemies, which could partially explain the benefits to the tended aphids. However, while ants did not provide a benefit to Aphis spp. when it was reared alone, in the presence of other species ant attendance increased Aphis abundance by 256% and simultaneously reduced E. lanigerum abundance by 63%. Therefore, ants benefited Aphis by reducing competition with other aphid species, which involves a different mechanism, explaining the benefit of ant attendance. Considering all the aphid species together, ants had a net positive effect on aphid abundance, which was consequently considered harmful for the plant. 5. Our results highlighted the role that ants play in structuring apple aphid communities and give support to the observed pattern that ants can benefit tended aphids while simultaneously reducing the abundance of untended herbivores.     

Complex phylogeographic patterns in the freshwater alga Synura provide new insights into ubiquity vs. endemism in microbial eukaryotes

The global distribution, abundance, and diversity of microscopic freshwater algae demonstrate an ability to overcome significant barriers such as dry land and oceans by exploiting a range of biotic and abiotic colonization vectors. If these vectors are considered unlimited and colonization occurs in proportion to population size, then globally ubiquitous distributions are predicted to arise. This model contrasts with observations that many freshwater microalgal taxa possess true biogeographies. Here, using a concatenated multigene data set, we study the phylogeography of the freshwater heterokont alga Synura petersenii sensu lato. Our results suggest that this Synura morphotaxon contains both cosmopolitan and regionally endemic cryptic species, co‐occurring in some cases, and masked by a common ultrastructural morphology. Phylogenies based on both proteins (seven protein‐coding plastid and mitochondrial genes) and DNA (nine genes including ITS and 18S rDNA) reveal pronounced biogeographic delineations within phylotypes of this cryptic species complex while retaining one clade that is globally distributed. Relaxed molecular clock calculations, constrained by fossil records, suggest that the genus Synura is considerably older than currently proposed. The availability of tectonically relevant geological time (10⁷–10⁸ years) has enabled the development of the observed, complex biogeographic patterns. Our comprehensive analysis of freshwater algal biogeography suggests that neither ubiquity nor endemism wholly explains global patterns of microbial eukaryote distribution and that processes of dispersal remain poorly understood.     

The composition of the polyglutamine‐containing proteins influences their co‐aggregation properties

The sequestration of crucial cellular proteins into insoluble aggregates formed by the polypeptides containing expanded polyglutamine tracts has been proposed to be the key mechanism responsible for the abnormal cell functioning in the so‐called polyglutamine diseases. To evaluate to what extent the ability of polyglutamine sequences to recruit other proteins into the intracellular aggregates depends on the composition of the aggregating peptide, we analysed the co‐aggregation properties of the N‐terminal fragment of huntingtin fused with unrelated non‐aggregating and/or self‐aggregating peptides. We show that the ability of the mutated N‐terminal huntingtin fragment to sequester non‐related proteins can be significantly increased by fusion with the non‐aggregating reporter protein [GFP (green fluorescence protein)]. By contrast, fusion with the self‐aggregating C‐terminal fragment of the CFTR (cystic fibrosis transmembrane conductance regulator) dramatically reduces the sequestration of related non‐fused huntingtin fragments. We also demonstrate that the co‐aggregation of different non‐fused N‐terminal huntingtin fragments depends on their length, with long fragments of the wild‐type huntingtin not only excluded from the nuclear inclusions, but also very inefficiently sequestered into the cytoplasmic aggregates formed by the short fragments of mutant protein. Additionally, our results suggest that atypical intracellular aggregation patterns, which include unusual distribution and/or morphology of protein aggregates, are associated with altered ability of accumulating proteins to co‐aggregate with other peptides.     

Ethnobotany of Mangroves among Jing People’s Folks

Mangrove plants are closely connected with folk customs of Jing ethnic group, and it is one of the symbols of Jing people as marine people. However, rapid economic development and globalization have brought about critical challenges to the cultural traditions of Jing people, and traditional knowledge of mangroves is being lost among Jing ethnic group. To protect folk customs on mangroves of Jing people, we have conducted a series of surveys on mangrove plants which have been used for folk customs of Jing people via ethnobotanical and taxonomical methods. The results showed that there were 14 mangrove plant species used in Jing people’s traditional folk customs. Four species of mangrove plants were used for religious belief, 11 species used in social customs and 7 species for material customs. Avicennia marina, Acanthus ilicifolius and Rhizophora stylosa are with the highest relationship with folk customs for Jing people. Our research can provide more comprehensive interpretation for characteristic on marine culture of Jing people, and improve the knowledge on ethnobotany of mangroves.     

重要谷类种子贮藏蛋白的特性及改良研究

在成熟谷类种子中,总蛋白约为种子干重的7％～16％,其中大部分为贮藏蛋白。这些贮藏蛋白对于人类和牲畜所需要的营养质量以及在食品加工中都有重要的影响。本文对一些重要谷类种子贮藏蛋白的组成特性以及利用基因工程技术提高谷类种子蛋白质含量和质量进行了全面综述。此外,还简要介绍了在利用基因工程改良谷物种子品质中可能产生的食品安全性问题、如何增加外源基因的表达量和全面提高谷类种子蛋白质含量以及解决的办法。     

ω-3多不饱和脂肪酸和三羟异黄酮孕期营养干预对母鼠及新生子代的影响

目的:了解孕期母鼠摄入ω-3多不饱和脂肪酸和三羟异黄酮对胎儿的影响。方法:采用刚怀孕的SD大鼠,进行孕期营养干预,观察营养物质对母鼠、新生子代大鼠的影响。结果:孕期营养干预对母鼠的孕期长短、产仔数量、性别比、雌激素水平影响没有统计学显著性差异,营养干预后的子代SD大鼠无出生缺陷的发生。结论:ω-3多不饱和脂肪酸和三羟异黄酮孕期营养干预对母鼠和子代无不良影响。     

HLA-DRB1 等位基因的多态性及其应用

HLA系统参与和调节机体免疫功能,是人类重要的遗传标志,具有种族、地域差异.HLA-Ⅱ类系统中DRB1等位基因的多态性最丰富,它的准确分型直接影响器官移植的供体选择、法医学个体认定、HLA与疾病相关性及人类学等研究.本文综述了HLA-DRB1分型检测方法,不同种族人群HLA-DRB1等位基因的多态性,HLA-DRB1多态性研究在探讨人类起源、民族融合方面的价值,HLA-DRB1与肝炎、系统性红斑狼疮等疾病的相关性等.     

硬化蛋白基因在淇河鲫成鱼不同肌间骨相邻肌组织的表达差异分析

为探究硬化蛋白(sclerostin, SOST)基因在淇河鲫肌间骨不同分布位置中的作用,以淇河鲫成鱼为研究对象,对其肌间骨的形态与分布进行了统计,并在此基础上利用qRT-PCR技术检测SOST基因在淇河鲫背部和尾部肌肉中的mRNA表达,通过Western印迹和免疫组织化学技术检测SOST蛋白的表达定位情况。结果显示：淇河鲫肌间骨包括髓弓小骨和脉弓小骨,髓弓小骨为56～58根,位于淇河鲫背部肌肉的肌隔中,脉弓小骨27～28根,分布于泄殖孔之后的肌隔中。背部肌肉SOST的mRNA表达水平显著高于尾部肌肉（P < 0.05）。与mRNA表达水平相比,背部肌肉和尾部肌肉中SOST蛋白呈现相同表达趋势。免疫组织化学结果显示SOST在肌隔组织中特异性表达,并且在背部肌肉中的表达强烈,尾部肌肉中没有阳性反应。上述结果表明,SOST在淇河鲫肌间骨的背部和尾部肌肉中存在差异性表达,从而影响肌隔组织中肌间骨的骨化,对背部和尾部肌间骨形态发生产生影响。     

两个大豆品种在暗棕壤和黑土中的根系形态和根瘤性状

选取黑龙江省2种主要农田土壤类型（暗棕壤和黑土）和2个大豆品种（滴2003-1和合丰25）,采用盆栽试验,分别于大豆第5片复叶展开期、初花期、结荚初期、结荚盛期、鼓粒初期、鼓粒期和完熟期取样,进行根系形态（根干质量、根长、根表面积和平均根直径等）和根瘤性状（根瘤数、根瘤鲜质量和单个根瘤质量）的动态分析,以研究品种和土壤类型对大豆根系形态特征的影响.结果表明：土壤类型对大豆根系形态及结瘤性状均有显著影响,在第5片复叶展开期和初花期,暗棕壤的根系干质量、根长和根表面积低于黑土,而在鼓粒初期后高于黑土,暗棕壤的平均根直径在鼓粒初期后也高于黑土,但土壤类型对根冠比的影响不大;暗棕壤的根瘤数在初花期后明显低于黑土,但根瘤鲜质量和单个根瘤质量高于黑土.不同品种的根系性状在2种土壤上的差异程度不同,与合丰25相比,滴2003-1的根系性状受土壤条件的影响较大.在鼓粒期,根干质量（P<0.05）、根表面积（P<0.05）、根瘤数（P<0.01）及单个根瘤质量（P<0.001）在不同品种与土壤类型间表现出显著的互作效应.     

古田山中亚热带常绿阔叶林动态监测样地——群落组成与结构

 亚热带常绿阔叶林是世界上主要植被类型之一,集中分布于我国,其中以中亚热带的常绿阔叶林最为典型。为了更好地研究常绿阔叶林森林生 物多样性维持机理,按照CTFS (Centre for Tropical Forest Science)样地建设的标准,于2004年11月～2005年9月在浙江开化古田山国家级 自然保护区建立了常绿阔叶林24 hm²永久样地。该文对样地内胸径≥1 cm的木本植物进行了统计,初步分析了古田山森林样地(Gutianshan (GTS) forest plot)的群落组成与空间结构。 群落的区系类型以热带成分比较多,在属的水平上53个是热带分布,44个是温带分布。共有159 种,隶属于49科103属,总计140 700株,以常绿树种为主（91个物种,占总优势度的90.6%,重要值为85.6%,占样地总个体数的85.9%）;样地 群落有明显的优势物种和大量稀有种(Rare species,每hm2个体数小于1)。甜槠(Castanopsis eyrei )、木荷(Schima superba)和马尾松 (Pinus massoniana)在群落中占有主要优势; 稀有种占总物种数的37.1％（59/159）;具有温带落叶阔叶林和热带雨林的相关特征,较好地代 表了中亚热带常绿阔叶林群落。垂直结构由林冠层（63个种）、亚乔木层（70个种）和灌木层 （26个种）组成。样地所有木本植物物种总径级 分布呈倒“J"形,群落更新良好。几个优势种空间分布随着径级增大,聚集程度降低;并且它们的分布表现出与生境紧密关联,不同的物种表 现出对生境不同的偏好。该文最后系统地比较了大样地方法与传统取样方法。