Kiwifruit floral gene APETALA2 is alternatively spliced and accumulates in aberrant indeterminate flowers in the absence of miR172

In Arabidopsis, the identity of perianth and reproductive organs are specified by antagonistic action of two floral homeotic genes, APETALA2 (AP2) and AGAMOUS (AG). AP2 is also negatively regulated by an evolutionary conserved interaction with a microRNA, miR172, and has additional roles in general plant development. A kiwifruit gene with high levels of homology to AP2 and AP2-like genes from other plant species was identified. The transcript was abundant in the kiwifruit flower, particularly petal, suggesting a role in floral organ identity. Splice variants were identified, all containing both AP2 domains, including a variant that potentially produces a shorter transcript without the miRNA172 targeting site. Increased AP2 transcript accumulation was detected in the aberrant flowers of the mutant 'Pukekohe dwarf' with multiple perianth whorls and extended petaloid features. In contrast to normal kiwifruit flowers, the aberrant flowers failed to accumulate miR172 in the developing whorls, although accumulation was detected at the base of the flower. An additional role during dormancy in kiwifruit was proposed based on AP2 transcript accumulation in axillary buds before and after budbreak.

Overexpression of the kiwifruit SVP3 gene affects reproductive development and suppresses anthocyanin biosynthesis in petals, but has no effect on vegetative growth, dormancy, or flowering time

SVP-like MADS domain transcription factors have been shown to regulate flowering time and both inflorescence and flower development in annual plants, while having effects on growth cessation and terminal bud formation in perennial species. Previously, four SVP genes were described in woody perennial vine kiwifruit (Actinidia spp.), with possible distinct roles in bud dormancy and flowering. Kiwifruit SVP3 transcript was confined to vegetative tissues and acted as a repressor of flowering as it was able to rescue the Arabidopsis svp41 mutant. To characterize kiwifruit SVP3 further, ectopic expression in kiwifruit species was performed. Ectopic expression of SVP3 in A. deliciosa did not affect general plant growth or the duration of endodormancy. Ectopic expression of SVP3 in A. eriantha also resulted in plants with normal vegetative growth, bud break, and flowering time. However, significantly prolonged and abnormal flower, fruit, and seed development were observed, arising from SVP3 interactions with kiwifruit floral homeotic MADS-domain proteins. Petal pigmentation was reduced as a result of SVP3-mediated interference with transcription of the kiwifruit flower tissue-specific R2R3 MYB regulator, MYB110a, and the gene encoding the key anthocyanin biosynthetic step, F3GT1. Constitutive expression of SVP3 had a similar impact on reproductive development in transgenic tobacco. The flowering time was not affected in day-neutral and photoperiod-responsive Nicotiana tabacum cultivars, but anthesis and seed germination were significantly delayed. The accumulation of anthocyanin in petals was reduced and the same underlying mechanism of R2R3 MYB NtAN2 transcript reduction was demonstrated.

Large networks of vertical multi-layer graphenes with morphology-tunable magnetoresistance

We report on the comparative study of magnetotransport properties of large-area vertical few-layer graphene networks with different morphologies, measured in a strong (up to 10 T) magnetic field over a wide temperature range. The petal-like and tree-like graphene networks grown by a plasma enhanced CVD process on a thin (500 nm) silicon oxide layer supported by a silicon wafer demonstrate a significant difference in the resistance-magnetic field dependencies at temperatures ranging from 2 to 200 K. This behaviour is explained in terms of the effect of electron scattering at ultra-long reactive edges and ultra-dense boundaries of the graphene nanowalls. Our results pave a way towards three-dimensional vertical graphene-based magnetoelectronic nanodevices with morphology-tuneable anisotropic magnetic properties. © The Royal Society of Chemistry 2013.

Multifunctional three-dimensional T-junction graphene micro-wells: Energy-efficient, plasma-enabled growth and instant water-based transfer for flexible device applications

The “third-generation” 3D graphene structures, T-junction graphene micro-wells (T-GMWs) are produced on cheap polycrystalline Cu foils in a single-step, low-temperature (270 °C), energy-efficient, and environment-friendly dry plasma-enabled process. T-GMWs comprise vertical graphene (VG) petal-like sheets that seemlessly integrate with each other and the underlying horizontal graphene sheets by forming T-junctions. The microwells have the pico-to-femto-liter storage capacity and precipitate compartmentalized PBS crystals. The T-GMW films are transferred from the Cu substrates, without damage to the both, in de-ionized or tap water, at room temperature, and without commonly used sacrificial materials or hazardous chemicals. The Cu substrates are then re-used to produce similar-quality T-GMWs after a simple plasma conditioning. The isolated T-GMW films are transferred to diverse substrates and devices and show remarkable recovery of their electrical, optical, and hazardous NO2 gas sensing properties upon repeated bending (down to 1 mm radius) and release of flexible trasparent display plastic substrates. The plasma-enabled mechanism of T-GMW isolation in water is proposed and supported by the Cu plasma surface modification analysis. Our GMWs are suitable for various optoelectronic, sesning, energy, and biomedical applications while the growth approach is potentially scalable for future pilot-scale industrial production.

Field evaluation of a plant activator, captan, chlorothalonil, copper hydroxide, iprodione, mancozeb and strobilurins for the control of citrus brown spot of mandarin

Brown spot (caused by Alternaria alternata) is a major disease of citrus in subtropical areas of Australia. A number of chemicals, the strobilurins azoxystrobin, trifloxystrobin, pyraclostrobin and methoxycrylate, a plant activator (acibenzolar), copper hydroxide, mancozeb, captan, iprodione and chlorothalonil/pyrimthanil were tested in the field for its control. Over three seasons, trees in a commercial orchard received 16, 14 and 7 fungicide sprays, respectively, commencing at flowering in the first season, and petal fall in the later seasons. In all experiments, the strobilurins used alone, or incorporated with copper and mancozeb, were as effective as, or better than the industry standard of copper and mancozeb alone. The only exception was trifloxystrobin, which when used alone was less effective than the industry standard. Acibenzolar used alone was ineffective. Applying a mixture of azoxystrobin and acibenzolar was found to reduce the incidence of brown spot compared with applying azoxystrobin alone but, in either case, disease levels were not found to be significantly different to the industry standard. Captan, iprodione and chlorothalonil/pyrimthanil were as effective as the industry standard. The incidence and severity of rind damage were significantly lowest in the azoxystrobin, methoxycrylate, iprodione and chlorothalonil/pyrimthanil treatments. Medium and high rates of trifloxystrobin (0.07 g/L, 0 .15 g/L) and pyraclostrobin (0.8 g/L, 1.2 g/L) applied alone were the only treatments found to be IPM-incompatible as shown by the elevated level of scale infection on fruit.

Suomi kasvitieteen kieleksi : Elias Lönnrot termistön kehittäjänä

The development of botanical Finnish: Elias Lönnrot as the creator of new terminology In the 19th century the Finnish language was intentionally developed to meet the demands of civilised society and Finnish-language science. The development of the language involved several people from different fields of science. This study examines this enormous project in the field of botany. By which methods were scientific terms formed, and for which reasons were those terms used? Why has a certain word been chosen to represent a particular concept? The material of this study is the terminology of plant morphology in Finnish that Elias Lönnrot developed in the middle of the 19th century. The terms of plant morphology denote and describe the parts of the plant and the relationships between those parts. For instance, the terms emi pistill , hede stamen , terälehti petal and verholehti sepal , which are nowadays familiar in the general language, were used for the first time in Lönnrot s texts. The study integrates the methods of lexicology and terminology. In lexicology, the word and its various meanings serve as the focus, whereas the theory of terminology focuses on the concept and concept systems. A new, consciously developed terminology can be understood through the old, familiar vocabulary and structures as well as through the new, logical term system. Lönnrot s botanical terminology can be divided into three groups depending on their origin: 1) 19% of all terms have been accepted from the existing vocabulary and used in their original meanings, 2) 11% of all terms have been chosen from the existing vocabulary and used in the new, specific botanical meanings, and 3) 70% of all terms have been created on the basis of the existing vocabulary and used in the new, specific botanical meanings. Therefore, the study reveals that domestic materials primarily morphosemantic neologisms form the Finnish terminology of plant morphology. Characteristic of Lönnrot s botanical terms is the utilisation of the vocabulary of various Finnish dialects and particular repeating elements. Repeating elements include, for example, the prefixes that come from botanical Latin or Swedish as well as the particular Finnish derivation types. Such structures form term systems that reflect scientific concept systems. Two thirds of the created new words are formed loosely or precisely according to either Latin or Swedish terms; one third is formed completely differently from its equivalents in the foreign languages. Approximately half of the chosen terms are formed differently from the Latin and Swedish terms. It is worth noting that many loan translations use rare vocabulary from Finnish dialects as equivalents to foreign parts of terms. Lönnrot aimed to inspire scientific terminology with Finland s own language, thus making scientific text accessible to the Finnish agricultural population.

Rickettsia-like-organisms and phytoplasmas associated with diseases in Australian strawberries

Strawberry lethal yellows (SLY) disease in Australia is associated with the phytoplasmas Candidatus Phytoplasma australiense and tomato big bud, and a rickettsia-like-organism (RLO). Ca. P. australiense is also associated with strawberry green petal (SGP) disease. This study investigated the strength of the association of the different agents with SLY disease. We also documented the location of SLY or SGP plants, and measured whether they were RLO or phytoplasma positive. Symptomatic strawberry plants collected from south-east Queensland (Australia) between January 2000 and October 2002 were screened by PCR for both phytoplasmas and the RLO. Two previously unreported disease symptoms termed severe fruit distortion (SFD) and strawberry leaves from fruit (SLF) were observed during this study but there was no clear association between these symptoms and phytoplasmas or the RLO. Only two SGP diseased plants were observed and collected, compared with 363 plants with SLY disease symptoms. Of the 363 SLY samples, 117 tested positive for the RLO, 67 tested positive for Ca. P. australiense AGY strain and 11 plants tested positive for Ca. P. australiense PYL variant strain. On runner production farms at Stanthorpe, Queensland the RLO was detected in SLY diseased plants more frequently than for the phytoplasmas. On fruit production farms on the Sunshine Coast, Queensland, Ca. P. australiense was detected in SLY disease plants more frequently than the RLO.

First Fruiting Intergeneric Hybrids between Citrus and Citropsis

Fruiting hybrids are reported for the first time between the genera Citrus L. and Citropsis (Engl.) Swing. & M.Kell. Conventional hybridization using the recently described species Citrus wakonai P.I.Forst. & M.W.Sm. and Citropsis gabunensis (Engl.) Swing. & M.Kell. resulted in high rates of fruit set and seed formation. Although seed were only half normal size, over 90% germinated without the need for embryo rescue techniques. Plant losses were high during the first few months but after six months, the 327 surviving hybrids were potted on. These grew vigorously on their own roots and 35 of them flowered within two years of sowing. Plants flowered continuously but all were pollen-sterile and ovaries abscised shortly after petal fall. However, at 25 months, two newly flowering hybrids began setting fruit. The development, identification, morphology, breeding efficiency, and future implications of this unique germplasm are described.

The Gerbera cDNA Microarray: A Tool for Large-Scale Identification of Genes Involved in Flower Development

During the past ten years, large-scale transcript analysis using microarrays has become a powerful tool to identify and predict functions for new genes. It allows simultaneous monitoring of the expression of thousands of genes and has become a routinely used tool in laboratories worldwide. Microarray analysis will, together with other functional genomics tools, take us closer to understanding the functions of all genes in genomes of living organisms. Flower development is a genetically regulated process which has mostly been studied in the traditional model species Arabidopsis thaliana, Antirrhinum majus and Petunia hybrida. The molecular mechanisms behind flower development in them are partly applicable in other plant systems. However, not all biological phenomena can be approached with just a few model systems. In order to understand and apply the knowledge to ecologically and economically important plants, other species also need to be studied. Sequencing of 17 000 ESTs from nine different cDNA libraries of the ornamental plant Gerbera hybrida made it possible to construct a cDNA microarray with 9000 probes. The probes of the microarray represent all different ESTs in the database. From the gerbera ESTs 20% were unique to gerbera while 373 were specific to the Asteraceae family of flowering plants. Gerbera has composite inflorescences with three different types of flowers that vary from each other morphologically. The marginal ray flowers are large, often pigmented and female, while the central disc flowers are smaller and more radially symmetrical perfect flowers. Intermediate trans flowers are similar to ray flowers but smaller in size. This feature together with the molecular tools applied to gerbera, make gerbera a unique system in comparison to the common model plants with only a single kind of flowers in their inflorescence. In the first part of this thesis, conditions for gerbera microarray analysis were optimised including experimental design, sample preparation and hybridization, as well as data analysis and verification. Moreover, in the first study, the flower and flower organ-specific genes were identified. After the reliability and reproducibility of the method were confirmed, the microarrays were utilized to investigate transcriptional differences between ray and disc flowers. This study revealed novel information about the morphological development as well as the transcriptional regulation of early stages of development in various flower types of gerbera. The most interesting finding was differential expression of MADS-box genes, suggesting the existence of flower type-specific regulatory complexes in the specification of different types of flowers. The gerbera microarray was further used to profile changes in expression during petal development. Gerbera ray flower petals are large, which makes them an ideal model to study organogenesis. Six different stages were compared and specifically analysed. Expression profiles of genes related to cell structure and growth implied that during stage two, cells divide, a process which is marked by expression of histones, cyclins and tubulins. Stage 4 was found to be a transition stage between cell division and expansion and by stage 6 cells had stopped division and instead underwent expansion. Interestingly, at the last analysed stage, stage 9, when cells did not grow any more, the highest number of upregulated genes was detected. The gerbera microarray is a fully-functioning tool for large-scale studies of flower development and correlation with real-time RT-PCR results show that it is also highly sensitive and reliable. Gene expression data presented here will be a source for gene expression mining or marker gene discovery in the future studies that will be performed in the Gerbera Laboratory. The publicly available data will also serve the plant research community world-wide.

The role of MADS and TCP transcription factors in Gerbera hybrida flower development

Angiosperms represent a huge diversity in floral structures. Thus, they provide an attractive target for comparative developmental genetics studies. Research on flower development has focused on few main model plants, and studies on these species have revealed the importance of transcription factors, such as MADS-box and TCP genes, for regulating the floral form. The MADS-box genes determine floral organ identities, whereas the TCP genes are known to regulate flower shape and the number of floral organs. In this study, I have concentrated on these two gene families and their role in regulating flower development in Gerbera hybrida, a species belonging to the large sunflower family (Asteraceae). The Gerbera inflorescence is comprised of hundreds of tightly clustered flowers that differ in their size, shape and function according to their position in the inflorescence. The presence of distinct flower types tells Gerbera apart from the common model species that bear only single kinds of flowers in their inflorescences. The marginally located ray flowers have large bilaterally symmetrical petals and non-functional stamens. The centrally located disc flowers are smaller, have less pronounced bilateral symmetry and carry functional stamens. Early stages of flower development were studied in Gerbera to understand the differentiation of flower types better. After morphological analysis, we compared gene expression between ray and disc flowers to reveal transcriptional differences in flower types. Interestingly, MADS-box genes showed differential expression, suggesting that they might take part in defining flower types by forming flower-type-specific regulatory complexes. Functional analysis of a CYCLOIDEA-like TCP gene GhCYC2 provided evidence that TCP transcription factors are involved in flower type differentiation in Gerbera. The expression of GhCYC2 is ray-flower-specific at early stages of development and activated only later in disc flowers. Overexpression of GhCYC2 in transgenic Gerbera-lines causes disc flowers to obtain ray-flower-like characters, such as elongated petals and disrupted stamen development. The expression pattern and transgenic phenotypes further suggest that GhCYC2 may shape ray flowers by promoting organ fusion. Cooperation of GhCYC2 with other Gerbera CYC-like TCP genes is most likely needed for proper flower type specification, and by this means for shaping the elaborate inflorescence structure. Gerbera flower development was also approached by characterizing B class MADS-box genes, which in the main model plants are known regulators of petal and stamen identity. The four Gerbera B class genes were phylogenetically grouped into three clades; GGLO1 into the PI/GLO clade, GDEF2 and GDEF3 into the euAP3 clade and GDEF1 into the TM6 clade. Putative orthologs for GDEF2 and GDEF3 were identified in other Asteraceae species, which suggests that they appeared through an Asteraceae-specific duplication. Functional analyses indicated that GGLO1 and GDEF2 perform conventional B-function as they determine petal and stamen identities. Our studies on GDEF1 represent the first functional analysis of a TM6-like gene outside the Solanaceae lineage and provide further evidence for the role of TM6 clade members in specifying stamen development. Overall, the Gerbera B class genes showed both commonalities and diversifications with the conventional B-function described in the main model plants.

Isolation of an 800 kb contiguous DNA fragment encompassing a 3.5-cM region of chromosome 1 in Arabidopsis using YAC clones

The apetalal mutation of Arabidopsis affects floral meristem identity and the development of sepal and petal primordia of the flower. We mapped the available RFLP markers on chromosome 1 that are in the general vicinity of apetalal on a fine structure map and then chose the closest RFLP as a starting point for contiguous DNA (contig) generation. We report here a contig of about 800 kilobases (kb) that spans a 3.5 cM region of chromosome 1. We used genomic libraries of Arabidopsis prepared in yeast artificial chromosome (YAC) vectors and the detailed characterization of 19 YACs is reported. RFLPs displayed by the end fragments from the walk were mapped to align and correlate the genetic and physical maps for this region of chromosome 1. In this segment of the genome, 1 cM corresponds to a little over 200 kb of physical distance.

Flower-like porous cobalt(II) monoxide nanostructures as anode material for Li-ion batteries

In the present study, a microwave-assisted, solution-based route has been employed to obtain porous CoO nano structures. Detailed characterization reveals that the flower-like nanostructures comprise petal-like sheets, each of which is made of an ordered, porous arrangement of crystallites of CoO measuring about 6 nm. TEM analysis shows that each ``petal'' is an oriented aggregate of CoO nanocrystals, such aggregation promoted by the hydroxyl moieties derived from the solution. The structure provides a large specific area as well as the porosity desirable in electrodes in Li-ion batteries. Electrochemical measurements carried out on electrodes made of nanostructured CoO show excellent Li ion-storing capability. A specific capacitance of 779 mAh g(-1) has been measured at a specific current of 100 mA g(-1). Measurements show also excellent cyclability and coulombic efficiency. Impedance spectroscopy provides evidence for charge transfer occurring in the porous networks. (C) 2015 Elsevier B.V. All rights reserved.

芍药花色形成的化学机制及其化学分类研究

本文以9 个芍药野生种（15 份种质）、104 个品种及2 个牡丹芍药组间杂种的花瓣为材料，利用液质联用技术鉴定了花瓣中的色素成分并探讨了芍药花色形成的化学机制和化学分类法。 结果表明，芍药花中主要含有5 种花青素，即芍药花素-3，5-二葡糖苷（ peonidin-3,5-di-O-glucoside ， Pn3G5G ）; 矢车菊素-3 ， 5- 二葡糖苷（ cyanidin-3,5-di-O-glucoside ， Cy3G5G ）; 天竺葵素-3 ， 5- 二葡糖苷（ pelargonidin-3,5-di-O-glucoside ， Pg3G5G ）; 芍药花素-3- 葡糖苷（peonidin-3-O-glucoside，Pn3G）和矢车菊素-3-葡糖苷（cyanidin-3-O-glucoside，Cy3G）。此外，3 种微量的花青素首次在芍药中发现：它们分别为芍药花素-3-葡萄糖-5-阿拉伯糖苷（peonidin-3-O-glucoside-5-O-arabinoside，Pn3G5Ara）、矢车菊素-3- 葡萄糖-5- 半乳糖苷（ cyanidin-3-O-glucoside-5-O-galactoside ，Cy3G5Gal）和天竺葵素-3-葡萄糖-5-半乳糖苷（pelargonidin-3-O-glucoside-5-Ogalactoside，Pg3G5Gal）。特征花青素Cy3G5Gal 和Pg3G5Gal 仅在新疆芍药（Paeonia anomala L.）及其亚种川赤芍（P. anomala subsp. veitchii(Lynch) D. Y.Hong & K. Y. Pan）中被检测出来，表明它们属于同一个种。Pn3G5Ara 仅存在于欧洲的野生芍药花瓣中，表明中国野生芍药和欧洲芍药的花青素代谢途径不同。 芍药花瓣中主要含有11 种花黄素，均为黄酮醇类物质。包括栎精-3，7 二葡糖苷（ quercetin-3,7-di-O-glucoside ）、山奈酚-3 ， 7 二葡糖苷（kaempferol-3,7-di-O-glucoside）、异鼠李素-3，7 二葡糖苷（isorhamnetin-3,7-di-Oglucoside）、栎精-3-O-(6”-没食子酰基)-葡糖苷 [quercetin-3-O-（6”-O-galloyl）-glucoside] 、栎精-3- 葡糖苷（ quercetin-3-O-glucoside ）、山奈酚-7- 葡糖苷（ kaempferol-7-O-glucoside ）、山奈酚-3-O- （ 6”- 没食子酰基） - 葡糖苷[kaempferol-3-O-（6”-O-galloyl)-glucoside]、异鼠李素-3-O-（6”-没食子酰基）-葡糖苷 [isorhamnetin-3-O- （ 6”-O-galloyl ） -glucoside] 、山奈酚-3- 葡糖苷（kaempferol-3-O-glucoside）、异鼠李素-3-葡糖苷（isorhamnetin-3-O-glucoside）和山奈酚-丙二酰葡糖苷（kaempferol-malonyl-glucoside）。此外，查耳酮在黄色的栽培品种‘黄金轮’和牡丹芍药组间杂交种‘伊藤杂种’中首次被检测到。其化学结构为查耳酮-2’-葡糖苷（chalcononaringenin 2’-O-glucoside），它是花瓣表现出黄色的主要色素，它与黄色牡丹野生种‘滇牡丹’（P. delavayi Franchet）花瓣中主要黄色色素成分一致。 通过对所有芍药野生种和栽培品种的色素分析，研究发现花青素是芍药花瓣中主要的色素，其中Pn3G5G 是花瓣中含量最高的花青素苷，其次为Cy3G5G。3G 型糖苷仅在少数品种中检测出来。此外，黄酮醇是芍药花瓣中重要的辅助色素。山奈酚苷是花瓣中含量最高的黄酮醇类，其次是栎精。 多元线性回归分析的结果表明，芍药花色的形成主要与花瓣中Pn3G5G、Cy3G5G 和Pg3G5G 的含量及总花青素量（TA）有关。根据8 种花青素结构与花色组成，将国内的野生种和大部分品种进行了化学分类：所有样本聚成3 大类，聚类后的树状图与其花色、花色素组成数据相一致，直观反映了野生种和栽培品种花色形成的化学背景和表型相似性程度。 芍药成色机理和化学分类的初步研究，对芍药新花色育种具有重要意义：芍药鲜红色花的育种中，育种亲本应具有高的Cy3G 含量、低的辅助色素效应指数。选育深紫色花或紫黑色花的品种，亲本应具有高的Pn3G5G 含量和低的Pg3G5G 含量。

Single-mode holey vertical-cavity surface-emitting laser with ultra-narrow beam divergence

We demonstrated oxide-confined 850-nm vertical-cavity surface-emitting lasers (VCSELs) with a two-dimensional petal-shaped holey structure composed of several annular-sector-shaped holes. Four types of devices with different hole numbers were designed and fabricated. The measured results showed that the larger hole number was beneficial to purifying the lasing mode, and realizing the single-mode operation. The side mode suppression ratio (SMSR) exceeded 30 dB throughout the entire drive current. Mode selective loss mechanism was used to explain the single-mode characteristic. The single-mode devices possessed good beam profiles, and the lowest divergence angle was as narrow as 3.2 degrees (full width at half maximum), attributed to the graded index profile and the shallow etching in the top distributed Bragg reflector (DBR).

中国蔷薇属芹叶组（Rosa Sect. Pimpinellifoliae DC. ex Ser.）的分类学研究

本研究通过我国CDBI、 KUN、PE、SZ等主要标本馆约3, 500份馆藏标本的研究和野外考察相结合，对我国蔷薇属（Rosa L.）芹叶组(Sect. pimpinellifoliae DC. ex Ser.）植物以及相关组的一些种进行了性状特征、形态和微形态的研究，对该组的一些种的形态特征描述进行了补充，同时给出详细的地理和海拔范围分布图。综合花粉以及种子（瘦果）形态的研究结果重新制订了分种检索表，同时，对该组一些形态相近容易混淆的种进行了对比研究，特别对一直存在争议的绢毛复合体（绢毛蔷薇R. sericea Lindl.和峨眉蔷薇R. omeiensis Rolfe）进行了大量宏观形态特征的研究，并用光学显微镜（LM）和扫描电镜(SEM)对二者的花粉及种子形态、微形态进行对比研究和分析，主要研究内容包括： 1. 芹叶组孢粉研究 对芹叶组的10个种及相关的4个组共17个种（18个样品）的植物花粉进行了光镜和扫描电镜观察和比较研究。研究结果表明：蔷薇属植物花粉粒大小为中等偏小，极轴长23.98[21.82(R. graciliflora Rehd. et Wils.)～29.18(R. tsinglingensis Pax. et Hoffm.)] μm，赤道轴长28.65[24.15（R. graciliflora）～34.70(R. davidii Crép.)] μm；花粉属辐射对称等极单花粉，花粉形态赤道面观呈球形到超长球形；极面观为三裂圆形或近圆形,三孔沟，孔缘加厚,具中部突起的桥状盖。花粉外壁纹饰为条纹状，光镜下形态特征相差不大；在电镜下外壁条纹和脊沟内穿孔的形状、大小和频度等特征，常具组至种水平上的可见变异，可作为组至种水平划分的依据。 根据花粉外壁条纹特征及穿孔形状和数目等特征，本研究将这些植物的花粉归为5个类型，并编制了分组检索表。同时，根据条纹状的清晰度，排列方式、条纹形状、穿孔大小及其频度等方面的差异，各有特点，对该组的10个种编制了分种检索表。 2. 芹叶组种子形态研究 应用光学显微镜和扫描电镜对我国蔷薇属芹叶组14个种及相关组5个组共36种植物的种子宏观形态及种皮微形态特征进行了观察研究。结果显示，蔷薇属种子形态多样,形状分别为肾形、卵形或锥形等；种子颜色以淡棕色、褐色以及土黄色为主；种子大小种间相差悬殊，相对体积为（长×宽×厚）36.66（4.79～114.47) mm3。光镜下，种子宏观形态特征具组内一致性，在扫描电镜下种子表面结构特征因种而异，其纹饰以网纹为主，可分为3种类型，即近平滑型、负网纹型和网纹型。研究结果表明，蔷薇属种子表面纹饰与地理分布关系不大,具有组及种内稳定性。其种子形态、大小、表而纹饰类型等特征可作为蔷薇属组及种水平上的分类依据。 结合蔷薇属花粉形态研究结果，得出蔷薇属种皮微形态特征与花粉外壁纹饰特征相吻合，在代表组及种的特征上具相关性的结论。同时根据种子形态、微形态结构特征的组间区别和种间差异编制了分组及芹叶组14个种的分种检索表。 3. 绢毛蔷薇复合体的研究 通过对大量标本的研究、野外观察以及扫描电镜对绢毛蔷薇复合体的花粉形态和种皮表面结构进行研究，通过对小叶、花粉及种子的形态定量分析结果支持Rowley (1959)的观点，将峨眉蔷薇处理为绢毛蔷薇的一个变种。 综上研究结果得出，蔷薇属植物的小叶片数目、花被基数以及花粉及种子形态等性状是较为稳定的，这些特征可很好的作为分类学依据。 The morphology, pollen exine sculpture and seed coat structure of the species of Rosa sect. Pimpinellifoliae and related sections were studied.About 3,500 herbarium specimens at CDBI, KUN, PE, and SZ were examined. Field work in Sichuan and Yunnan were conducted. Revisions of some species were carried out and a new key to species of sect. Pimpinellifoliae was proposed based on morphology, pollen exine sculpture and seed coat structure, Detailed morphological descriptions, geographical distributions and the altitudinal ranges of some taxa are given. The systematics of the species complex, the Rosa sericea complex (R. sericea Lindl. & R. omeiensis Rolfe), was emphasized. This thesis focused on the following three aspects: 1. Pollen morphology of Rosa sect. Pimpinellifoliae The pollen morphology of 18 samples representing 10 species of the Eurasian Rosa sect. Pimpinellifoliae and 7 additional species of related sections was investigated under LM and SEM. The pollen grains are monadic, actinomorphic, equipolar, medium-sized, spheroidal to perprolate in equatorial view, 3-lobed circular or semi-circular in polar view, crassimarginate, pontoperculate, and with striate exine sculpture. The striate sculpture varies among sections and species. The equatorial axis ranges from 17.97 μm (R. sikangensis) to 29.18 μm (R. tsinglingensis) with an average of 23.98 μm in length, while polar axis varies from 24.15 μm (R. gracilifolra) to 34.70 μm (R. davidii) with an average of 28.65 μm in length. The pollens can be divided into five types based on striate sculpture and a key to the sections sampled was proposed accordingly. The pollen morphology of species of sect. Pimpinellifoliae is more homogeneous and different from other sections sampled and did not support the two-series subdivisions in sect. Pimpinellifoliae. A key is also provided based on characers of pollen morphology among species in sect. Pimpinellifoliae. 2. Seed coat structure of Rosa sect. Pimpinellifoliae The seed coat structure of 39 samples representing 14 species of Rosa sect. Pimpinellifoliae and 12 additional species of related sections was investigated under LE and SEM. The seed relative volume (Length × width × thickness) ranges from 4.79 to 114.47 mm3 with an average of 36.66. mm3. The seeds are reniform, ovate or oblong in shape, with orange-brown, light brown or deep brown color. Seed coat sculpture was reticulate or striate-like reticulate. There was no difference in sculpture character of various speices under LM, while three types of seed coat sculpture were identified under SEM and a key to species based on the seed coat sculpture was provided. The three types of seed coat sculpture were nearly smooth, areolate and reticulate. The study of the seed coat sculpture of same species sampled from different populations showed that characters on the seed coat are stable, and thus the size, shape and seed coat sculpture can be used in species level identification. Interestingly, characters in the seed coat sculpture and the pollen morphology in sect. Pimpinellifoliae are consistent at in specific or sectional levels. A key to the 14 species sampled was given based on seed coat sculpture. 3. The study on Rosa sericea complex The Rosa sericea complex contains R. omeiensis and R. sericea. They are morphologically similar to one another and the systematic status of R. omeiensis has been controversial. In this study we examined large numbers of herbarium specimens of R. omeiensis and R. sericea and conducted field observations in the Hengduan Mts.. We also performed SEM study of pollen morphology and seed coat structure of R. omeiensis and R. sericea. We further carried out intensive morphometric study on the leaflet, pollen, and seed morphology. Our results showed that R. omeiensis should be sunk to be a variety of R. sericea, just as Rowley’s treatment in 1959. In conclusion, the features in the number of leaflet and petal, and the morphological character on pollen and seed are relatively stable. Therefore these characters are very useful in taxon delimition.