Bolboschoenus planiculmis (F.Schmidt) T.V.Egorova is a typical wetland plant in the species-rich Cyperaceae family. This species contributes prominently to carbon dynamics and trophic integration in wetland ecosystems. Previous studies have reported that the chromosomes of B. planiculmis are holocentric; i.e. they have kinetic activity along their entire length and carry multiple centromeres. This feature was suggested to lead to a rapid genome evolution through chromosomal fissions and fusions and participate to the diversification and ecological success of the Bolboschoenus genus. However, the specific mechanism remains uncertain, partly due to the scarcity of genetic information on Bolboschoenus. We present here the first chromosome-level genome assembly for B. planiculmis. Through the integration of high-quality long-read and short-read data, together with chromatin conformation using Hi-C technology, the ultimate genome assembly was 238.01 Mb with a contig N50 value of 3.61 Mb. Repetitive elements constituted 37.04% of the genome, and 18,760 protein-coding genes were predicted. The low proportion of long terminal repeat retrotransposons (similar to 9.62%) was similar to that reported for other Cyperaceae species. The Ks (synonymous substitutions per synonymous site) distribution suggested no recent large-scale genome duplication in this genome. The haploid assembly contained a large number of 54 pseudochromosomes with a small mean size of 4.10 Mb, covering most of the karyotype. The results of centromere detection support that not all the chromosomes in B. planiculmis have multiple centromeres, indicating more efforts are needed to fully reveal the specific style of holocentricity in cyperids and its evolutionary significance.

Abstract Kobresia species are common in meadows on the Qinghai–Tibet Plateau. They are important food resources for local livestock, and serve a critical foundation for ecosystem integration. Genetic resources of Kobresia species are scarce. Here, we generated a chromosome-level genome assembly for K. myosuroides (Cyperaceae), using PacBio long-reads, Illumina short-reads, and Hi–C technology. The final assembly had a total size of 399.9 Mb with a contig N50 value of 11.9 Mb. The Hi–C result supported a 29 pseudomolecules model which was in consistent with cytological results. A total of 185.5 Mb (44.89% of the genome) transposable elements were detected, and 26,748 protein-coding genes were predicted. Comparative analysis revealed that Kobresia plants have experienced recent diversification events during the late Miocene to Pliocene. Karyotypes analysis indicated that the fission and fusion of chromosomes have been a major driver of speciation, which complied with the lack of whole-genome duplication (WGD) in K. myosuroides genome. Generally, this high-quality reference genome provides insights into the evolution of alpine sedges, and may be helpful to endemic forage improvement and alpine ecosystem preservation.

Spring ephemeral plants that experience harsh environments have developed specific reproductive characteristics. These characteristics are of great importance to the survival and reproduction of these species, particularly for rare and endangered plants. Fritillaria is a genus consisting of spring ephemeral plants with significant medicinal and ornamental value whose wild resources are highly threatened and whose reproductive characteristics and adaptative evolutionary mechanisms are still not well understood. Fritillaria maximowiczii is positioned at the most basal clade on the Fritillaria phylogenetic tree, whose reproductive characteristics remain obscure. In this study, we report the flowering dynamics, pollination biology and breeding system of F. maximowiczii. The flowering process of F. maximowiczii can be divided into seven stages. Based on the pollen/ovule ratio, the outcrossing index and a field pollination experiment on a natural population, F. maximowiczii showed high levels of outcrossing and self-compatibility. Three types of pollinators were observed: two kinds of bumblebees, and spiders. Diverse herkogamy and dichogamy may have considerably improved its reproductive success rate. Furthermore, a special reproductive mode not previously reported in wild populations of Fritillaria, apomixis, was strongly suspected based on a high fruit setting rate (36.84%). Our study suggests F. maximowiczii has developed multiple reproductive strategies to adapt to harsh environments and ensure population reproduction, and the diverse reproductive mechanisms may be related to its primitive phylogenetic position in the genus. This study not only broadens our understanding of mechanisms of ecological adaptation in spring ephemeral plants but also provides key data for the conservation of Fritillaria.

Characterizing genetic diversity and structure and identifying conservation units are both crucial for the conservation and management of threatened species. The development of high-throughput sequencing technology provides exciting opportunities for conservation genetics. Here, we employed the powerful SuperGBS method to identify 33, 758 high-quality single-nucleotide polymorphisms (SNP) from 134 individuals of a critically endangered montane shrub endemic to North China, Lonicera oblata. A low level of genetic diversity and a high degree of genetic differentiation among populations were observed based on the SNP data. Both principal component and phylogenetic analyses detected seven clusters, which correspond exactly to the seven geographic populations. Under the optimal K = 7, Admixture suggested the combination of the two small and geographically neighboring populations in the Taihang Mountains, Dongling Mountains, and Lijiazhuang, while the division of the big population of Jiankou Great Wall in the Yan Mountains into two clusters. High population genetic diversity and a large number of private alleles were detected in the four large populations, while low diversity and non-private alleles were observed for the remaining three small populations, implying the importance of these large populations as conservation units in priority. Demographic history inference suggested two drastic contractions of population size events that occurred after the Middle Pleistocene Transition and the Last Glacial Maximum, respectively. Combining our previous ecological niche modeling results with the present genomic data, there was a possible presence of glacial refugia in the Taihang and Yan Mountains, North China. This study provides valuable data for the conservation and management of L. oblata and broadens the understanding of the high biodiversity in the Taihang and Yan Mountains.

《诗经》是中国最早的诗歌总集,它既是中国古代诗歌的开端,也是反映周朝社会生活的一部独具一格的百科全书,记录了周王朝由盛而衰五百年间中国社会生活的基本面貌. 花椒?胡椒?还是辣椒? 《诗经》中有三篇与"椒"有关的诗歌,它们也是中国饮食文化史上最早记载"椒"的诗句,分别是《诗经·唐风·椒聊》《诗经·国风·陈风·东门之枌》和《诗经·周颂·载芟》.

Carex myosuroides Villars, 1779 is a typical alpine sedge with both ecological and agricultural value. The work reported here is the first complete chloroplast genome of this species. The chloroplast genome, with a total size of 185,609 bp, consists of two inverted repeats (IRs, 38,374 bp) separated by a large single-copy (LSC, 99,911 bp) region, and a small single-copy (SSC, 8950 bp) region. The overall genome GC content is 34.12%. The genome contains 125 genes, consisting of 82 protein-coding genes, 35 tRNA genes, and eight rRNA genes. Phylogenetic analysis supports the taxonomic treatment of incorporating genus Kobresia to a broader circumscription of Carex. Our work could be helpful to future research on Cyperaceae.

An inventory of vascular plants in a region is of great significance for regional plant diversity conservation and sustainable utilization of plant resources.Beijing is the capital of China, where the inventory work has been carried out early since the 1960s, but it has not been systematically updated in the past three decades.Currently, the existing data is outdated, scattered and unsystematic, and the inventory progress has even fell behind the neighbouring areas of Beijing.Based on the inventory of vascular plants from the Flora of Beijing (1992 Revised Edition) and combined with the field survey from many years, we have composed a dataset on new inventory and geographical distributions of vascular plants in Beijing (including two sheets for native plants and introduced plants, the latter is incomplete currently), by supplementing with new taxa, new records and new distributions from comprehensive literatures, revising the scientific names (based on the new revision of classification), updating the classification systems (using those based on molecular data), and also adding some related information such as taxon rank, distribution status, growth status, outdoor/indoor, distribution areas, knowledge degree and conservation status.Up to December 31, 2021, the dataset has a total of 2,883 data items, with 1,680 items for native plants and 1,203 for introduced plants.There are 134 families, 611 genera, 1,597 taxa (1,440 species 3 natural hybrids 46 subspecies 97 varieties and 11 forms) of native wild vascular plants in Beijing, and totally 3 families, 26 genera, 173 species 4 subspecies 28 varieties and 11 forms should be supplemented to the last version of Flora of Beijing.The Beijing native wild plants included in the 'List of National Key Protected Wild Plants (2021)' have only been counted for 16 species (only 1 at the first class, others all at the second class).There are also 90 species 3 subspecies and 4 varieties included in the 'List of Beijing Key Protected Wild Plants ( 2008)'.On introduced plants, so far 137 families, 581 genera and 1,184 taxa (992 species and other infraspecific taxa) are counted, including many cultivated plants (854 species 19 hybrids 15 subspecies 29 varieties 2 forms 87 cultivars 38 cultivar groups).There are still escape plants (132 species 1 subspecies), naturalized plants (77 species 2 varieties), and invasive plants (27 species) in Beijing.The dataset shows that the diversity of native wild vascular plants in Beijing is generally not very abundant, mainly dominated by widely distributed common species, and lacking endemic species, narrow-range species, or rare and endangered species; meanwhile, there are a large number of introduced plants in Beijing.Even many have long been recorded in the versions of Flora of Beijing but they are also an important part of the diversity of vascular plants in Beijing, although they also bring some confusion and uncertainty to the analysis of it due to the incomplete data.

Background Plants in cliff habitats may evolve specific reproductive strategies to cope with harsh environments, and unraveling these reproductive characteristics can improve our understanding of survival strategies and lithophyte evolution. This understanding is especially important for efforts to protect rare and endemic plants. Here, we investigated the reproductive biology of Lonicera oblata, an endangered lithophytic shrub that is scattered in highly fragmented and isolated cliff habitats of the Taihang and Yan mountains in North China. Results Flowers of L. oblata are herkogamous and protandrous, characteristics that can prevent autogamy at the single-flower level, and insects are necessary for pollination. The outcrossing index, pollen/ovule ratio, and the results of hand pollination were measured and all revealed a mixed mating system for L. oblata, that combines cross-fertilization and partial self-fertilization. The floral traits of L. oblata of zygomorphic and brightly yellowish corolla, heavy fragrance, and rich nectar, suggest an entomophilous pollination system. Sweat bees were observed as the most effective pollinators but their visiting frequencies were not high. Pollen limitation may limit the reproductive success of L. oblata. Conclusions We determined the reproductive characteristics of L. oblata, a critically endangered species endemic to cliffs in North China, providing insight into its endangerment and suggesting conservation strategies. L. oblata has highly pollinator-dependent self-fertilization as part of a mixed mating system. Floral features such as low-flowering synchrony, asynchronous anthers dehiscence, and high duration of stigma receptivity, improve pollination efficiency in the case of low pollinator service. Our work provides reference information to understand the survival strategies and conservation of L. oblata and other lithophytes.

莲、荷与睡莲 "荷"字最早的文字记载是在春秋战国时期的《诗经》中,里边有3首关于"荷"的诗歌:《邶风·简兮》、《郑风·山有扶苏》和《陈风·泽陂》."莲"字最早出现在东汉班固的《白虎通德论》中,使用的词汇是"莲莆",这个词既是植物名,指的是"树名也,其叶大于门扇";也是地名,指的是东汉的"莲州"与"莆州",但具体地址已不可考.

旨在对北京地区分布的佛法僧目(Coraeiiformes)翠鸟科(Alcedinidae)的蓝翡翠(Halcyon pileata)以及佛法僧科(Coraciidae)的三宝鸟(Eurystomus orientalis)主要类型羽毛进行微观结构对比观察.实验流程为:鸟类标本取样前再鉴定、确定采样位置、取样、样品脱脂、超声波清洗、自然干燥、离子溅射喷金及扫描电子显微镜观察.结果 表明:飞羽、尾羽和体羽主要由有钩羽小枝和无钩羽小枝构成;有钩羽小枝和无钩羽小枝相互啮合形成坚实的羽面来减少飞行阻力.两种鸟类的有钩羽小枝中的小钩数,无钩羽小枝中的腹齿数,数量恒定且相同.绒羽中节状羽小枝膨大节的形状,区别明显.根据现有结果及文献资料,涉及到的两科羽毛在上述各部分羽毛参数差别恒定并且明显,可以作为科级鉴定参考.

以北京市Ⅱ级重点保护野生植物百花山葡萄(Vitis baihuashanensis M.S.Kang et D.Z.Lu)为研究对象,通过对其野生个体所在群落和人工扩繁个体所在群落进行样方调查,定量分析百花山葡萄自然群落的生态位特征和种间联结关系,对比人工群落的相关情况,探讨其濒危原因.结果 显示:百花山葡萄自然群落总体呈正相关,物种正负关联比小于1,仍在向稳定群落发育;由于高大乔木和上层优势灌木截获了大量光照,以及高生态位重叠物种小花溲疏(Deutzia parviflora Bge.)、牛叠肚(Rubus crataegifolius Bge.)、短尾铁线莲(Clematis brevicaudata DC.)、五味子(Schisandra chinensis (Turcz.) Baill.)对各类资源的夺取,使百花山葡萄的营养生长受到明显限制.人工群落总体呈正相关,主要物种正负关联比大于1,目前处于相对较稳定状态;该群落缺乏高大乔木,光照充足,百花山葡萄与圆柏(Sabina chinensis (L.) Ant.)幼树等优势灌木呈不显著正相关,所受竞争压力相对较小,植株已进入生殖生长阶段.建议加强对百花山葡萄自然群落的人工抚育,适当疏枝、疏灌、疏藤,提高和改善百花山葡萄的光照条件,降低其他物种的资源竞争力度,以提高其在群落内的竞争能力,提升物种保护成效.

考察队员们从太白山北坡徒步登顶,由低海拔到高海拔先后见到阔叶林和针阔混交林,穿越高山杜鹃矮林和太白红杉林,偶遇隐居山中的独叶草,饱览高山灌丛草甸和冰川地貌. 秦岭跨越我国甘肃、陕西和河南三省,东西绵延1600千米,南北宽几百千米.独特的地理位置和气候环境孕育了丰富的生物资源,在自然科学和人文科学研究领域均占有重要地位,拥有“中国大陆的南北分水岭”“中国中央大花园”“自然科学研究的天然实验室” “中国的父亲山”等美名.

为系统地研究北京地区雨燕科3种雨燕的羽毛特点,给雨燕科的保护、分类研究积累资料,笔者对北京地区分布的雨燕目(Apodiformes)雨燕科(Apodidae)的白腰雨燕(Apus pacificus)、普通楼燕(Apus apus)、白喉针尾雨燕(Hirundapus caudacutus)主要类型羽毛进行微观结构对比观察.试验流程为:鸟类标本取样前再鉴定、确定采样位置、取样、样品脱脂、超声波清洗、自然干燥、离子溅射喷金及扫描电子显微镜观察.结果 表明:飞羽、尾羽和体羽主要有钩羽小枝和无钩羽小枝构成;有钧羽小枝和无钩羽小枝相互啮合形成坚实的羽面来减少飞行阻力.3种鸟类羽毛的飞羽羽小轴表面纹饰、绒羽节点形状可以作为属间分类重要特征,飞羽、尾羽及体羽其他特征参数可以作为参考.

通过使用比较形态学及文献考证等方法,分析了乾隆《具有生趣》图卷上9种植物的特征,对其分类学位置进行考释,确定出其中的8种植物,分别是牡丹、羊蹄甲、荷包牡丹、春兰、射干、月季、梅花和桃花.对该图卷的成形时期进行分析,发现该图卷成形的时期与西方的现代植物分类学奠基人林奈发明植物双名法的时期基本一致.白描绘画技法的应用,使中国人对植物典型分类群特征的描绘更加准确.

花序苞片是椴树属最典型的特征,但它与其他器官的演化关系尚不明确.本文对华东椴(Tilia japonica Simonk.)花序苞片和叶片在生长发育上的关联性进行分析,并对其表面微形态特征和内部解剖结构进行详细比较.结果 显示,华东椴苞片和叶片在生长发育过程中表现出非常相似的规律性,二者在苞片幼期阶段均生长迅速、中期阶段生长变缓、成熟阶段再有小幅生长.对苞片与叶片形态性状的相关性分析显示,苞片长、苞片宽、叶长、叶宽的相关性均极显著.在表面微形态特征上,苞片和叶片总体上非常相似;在解剖特征上,苞片没有栅栏组织和海绵组织的分化,叶片有明显的分化.结合椴树属苞片的化石记录,我们认为椴树属苞片最早由叶片特化而来,是一种叶状结构,二者在表皮微形态特征及解剖结构上的差异,主要是在演化过程中为了适应各自不同功能而逐渐产生的.

唐朝白居易在《后宫词》中说:“三千宫女胭脂面,几个春来无泪痕”;南唐李煜在《相见欢·林花谢了春红》中唱到:“胭脂泪,相留醉,几时重.自是人生长恨,水长东”;宋朝苏轼的《蝶恋花·雨霰疏疏经泼火》中有:“杏子梢头香蕾破,淡红褪白胭脂涴”等等.那么,这些诗词歌赋中的“胭脂”是什么东西呢?

用扫描电子显微镜对反嘴鹬科 Recurvirostridae的鹮嘴鹬Ibidorhyncha struthersii、黑翅长脚鹬Himantopus himantopus不同部位羽毛进行了超微结构观察.结果表明:飞羽、尾羽和体羽主要有有钩羽小枝和无钩羽小枝构成;有钩羽小枝和无钩羽小枝相互哧合形成坚实的羽面来减少飞行阻力.两种鸟类的飞羽、尾羽及体羽的有钩羽小枝中的小钩、纤毛及腹齿数目恒定且相同,可以作为科级鉴定标准.无钩羽小枝中的疵,状突起为新发现,数目恒定且不同,可以与绒羽中节状羽小枝节间长度指标作为属级鉴定标准.

Lonicera oblata, a critically endangered species endemic to North China with about 30 wild individuals, has long been ignored for conservation since its publication because of little attention on its living situation. In this study, we characterized the complete chloroplast (cp) genome of L. oblata. The cp genome was 155,481 bp in length, included a large single-copy (LSC) region of 89,139 bp, a small single-copy (SSC) region of 18,676 bp, and two inverted repeat (IR) regions of 23,833 bp each. The genome contains 130 genes, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Phylogenetic position of L. oblata was also investigated based on cp genome phylogeny of Lonicera representatives. This study is valuable for molecular phylogenetic study and conservation of Lonicera and related taxa.

常常听到喜欢吃洋葱的朋友表达出对洋葱又爱又恨的感情:爱的是它鲜美爽脆的口感,恨的是切开它时哗哗留下的眼泪.那么,为什么会出现这种情况呢?让我们一起来认识认识洋葱吧. 洋葱概述 洋葱是一种较为常见的植物性食材,在我们身边的菜市场、餐桌上均能见到它.它的叶子为绿色管状的,叶子的表面有一层蜡质.叶鞘肥厚,像鳞片状,密集分布在短缩的茎的周围,形成了植物学上一种特殊的结构——鳞茎,也就是我们常说的洋葱头.洋葱,是百合科的一种植物,它的花是伞状花序,花序中的小花是白色的,结的果子是蒴果.

Background Elaiosomes are specialized fleshy and edible seed appendages dispersed by ants. Lipids are the primary components of elaiosomes. Chelidonium majus is a well-known plant, the seeds of which are dispersed by ants. Previous studies have identified the presence of primary fatty acids in its elaiosomes and seeds. However, the molecular mechanisms underlying fatty acid biosynthesis in elaiosomes remain unknown. Methods In order to gain a comprehensive transcriptional profile of the elaiosomes and seeds of C. majus, and understand the expression patterns of genes associated with fatty acid biosynthesis, four different developmental stages, including the flower-bud (Ch01), flowering (Ch02), young seed (Ch03), and mature seed (Ch04) stages, were chosen to perform whole-transcriptome profiling through the RNA-seq technology (Illumina NGS sequencing). Results A total of 63,064 unigenes were generated from 12 libraries. Of these, 7,323, 258, and 11,540 unigenes were annotated with 25 Cluster of Orthologous Groups, 43 Gene Ontology terms, and 373 Kyoto Encyclopedia of Genes and Genomes pathways, respectively. In addition, 322 genes were involved in lipid transport and metabolism, and 508 genes were involved in the lipid metabolism pathways. A total of 41 significantly differentially expressed genes (DEGs) involved in the lipid metabolism pathways were identified, most of which were upregulated in Ch03 compared to Ch02, indicating that fatty acid biosynthesis primarily occurs during the flowering to the young seed stages. Of the DEGs, acyl-ACP thioesterases, acyl carrier protein desaturase (DESA1), and malonyl CoA-ACP transacylase were involved in palmitic acid synthesis; stearoyl-CoA desaturase and DESA1 were involved in oleic acid synthesis, and acyl-lipid omega-6 desaturase was involved in linoleic acid synthesis.