Phenolic compounds of the subfamily pomoideae: A chemotaxonomic survey

The subfamily Pomoideae has been surveyed for leaf phenolics and it has been shown that flavone glycosides are present in the genera Sorbus, Aronia, Chaenomeles and Hesperomeles in addition to the previously reported occurrences in Crataegus, Malus and Pyrus. The dihydrochalcone phloridzin, a typical constituent of Malus, has also been found in Docynia. Arbutin and phenolic acid-calleryanin esters are apparently restricted to Pyrus. Naringenin and eriodictyol glucosides have been detected in Pyracantha, Sorbus, Photinia, Chaenomeles and Hesperomeles. A number of Pomoideae phenolics have been found in two Spiraeoideae genera; luteolin 7-glucoside,] luteolin 7-diglucoside, luteolin 7-rhamnosylglucoside and apigenin 7-glucoside in Exochorda and the dihydrochalcone trilobatin in Sorbaria. The chemotaxonomic evidence is consistent with the hypothesis that the Pomoideae evolved through a process of allopolyploidy from primitive members of the Spiracoideae and Prunoideae.     

中国特有属牛筋条属的花粉形态与其系统位置

从发育的角度研究了中国特有单种属DichotomanthesKurz及与其系统学研究有关的外类群Prinsepiautilis的花粉形态 ,扫描电镜观察显示Dichotomanthes花粉粒自脱离四分体胼胝质膜开始至成熟二核花粉粒不同发育时期 ,花粉形态和外壁纹饰未见变化 ,仅花粉体积随成熟度增加而有所增大。而Prinsepiautilis ,其花粉粒刚脱离四分体时形状和成熟花粉明显不同 ,成熟花粉极面观为三裂圆形 ,赤道面观为圆形 ,外壁具清晰的平行条纹 ,但幼嫩花粉粒的形状很特别 ,极面观为深三裂圆形 ,赤道面观亦见花粉在两条沟之间下陷而沟部外突 ,明显为角萌发孔花粉 ,且花粉体积较成熟者小 ,而外壁纹饰同成熟者相比无根本性差异。前述两种植物花粉在不同成熟期体积有明显差异 ,而外壁纹饰在不同成熟期不存在质的变化并相对稳定 ,说明花粉外壁纹饰这一性状在蔷薇科中具有较为重要的分类学意义。DichotomanthesKurz具典型Rosaceae花粉的三孔沟结构 ,外壁具条纹 -穴状纹饰。将其孢粉学特征同Rosaceae 4个亚科有关类群的同类资料相比较 ,并结合其它形态解剖与细胞学等研究结果 ,支持将Dichotoman thes置入Maloideae下而不赞同将其另立亚科或置于Prunoideae之下。此外 ,由于Prinsepiautilis的花粉在其发育初期具角萌发孔花粉 ,与Cunoniacea     

Distribution of sorbitol in rosaceae

77 leaf samples representing 68 taxa of Rosaceae were investigated for the presence of sorbitol. A procedure for the quantitative estimation of sorbitol in dry plant tissues was elaborated; it made use of extraction by percolation and capillary GLC analysis of the silylated extracts. All Maloideae and Prunoideae and most Spiraeoideae were found to accumulate sorbitol. The subfamily Rosoideae was found to be heterogeneous in this respect; in most tribes sorbitol is totally lacking, but in Kerrieae, Adenostomeae and part of Dryadeae sorbitol is present in variable amounts. A clear-cut correlation between sorbitol accumulation and basic chromosome number seems to exist in Rosaceae.     

The granule-bound starch synthase (GBSSI) gene in the Rosaceae: multiple loci and phylogenetic utility

We sampled the 5' end of the granule-bound starch synthase gene (GBSSI or waxy) in Rosaceae, sequencing 108 clones from 18 species in 14 genera representing all four subfamilies (Amygdaloideae, Maloideae, Rosoideae, and Spiraeoideae), as well as four clones from Rhamnus catharticus (Rhamnaceae). This is the first phylogenetic study to use the 5' portion of this nuclear gene. Parsimony and maximum-likelihood analyses of 941 bases from seven complete and two partial exons demonstrate the presence of two loci (GBSSI-1 and GBSSI-2) in the Rosaceae. Southern hybridization analyses with locus-specific probes confirm that all four Rosaceae subfamilies have at least two GBSSI loci, even though only one locus has been reported in all previously studied diploid flowering plants. Phylogenetic analyses also identify four clades representing four loci in the Maloideae. Phylogenetic relationships inferred from GBSSI sequences are largely compatible with those from chloroplast (cpDNA: ndhF, rbcL) and nuclear ribosomal internal transcribed spacer (nrITS) DNA. Large clades are marked by significant intron variation: a long first intron plus no sixth intron in Maloideae GBSSI-1, a long fourth intron in Rosoideae GBSSI-1, and a GT to GC mutation in the 5' splice site of the fourth intron in all GBSSI-2 sequences. Our data do not support the long-held hypothesis that Maloideae originated from an ancient hybridization between amygdaloid and spiraeoid ancestors. Instead, Spiraeoideae genera (Kageneckia and Vauquelinia) are their closest relatives in all four GBSSI clades.     

Phylogeny and classification of Rosaceae

Phylogenetic relationships among 88 genera of Rosaceae were investigated using nucleotide sequence data from six nuclear (18S, gbssi1, gbssi2, ITS, pgip, and ppo) and four chloroplast (matK, ndhF, rbcL, and trnL-trnF) regions, separately and in various combinations, with parsimony and likelihood-based Bayesian approaches. The results were used to examine evolution of non-molecular characters and to develop a new phylogenetically based infrafamilial classification. As in previous molecular phylogenetic analyses of the family, we found strong support for monophyly of groups corresponding closely to many previously recognized tribes and subfamilies, but no previous classification was entirely supported, and relationships among the strongly supported clades were weakly resolved and/or conflicted between some data sets. We recognize three subfamilies in Rosaceae: Rosoideae, including Filipendula, Rubus, Rosa, and three tribes; Dryadoideae, comprising the four actinorhizal genera; and Spiraeoideae, comprising Lyonothamnus and seven tribes. All genera previously assigned to Amygdaloideae and Maloideae are included in Spiraeoideae. Three supertribes, one in Rosoideae and two in Spiraeoideae, are recognized.     

The Evolution and Distribution of Subfam. Spiraeoideae (Rosaceae) of China,with Special Reference to Distribution of the Subfamily in the World

The subfam. Spiraeoideae, consisting of 22 genera and more than 260 species in the world,is the most primitive subfamily of Rosaceae. It has developed into two groups,i.e. evergreen and deciduous ones, of which eight genera and 100 species in China are totally deciduous. In the present paper, the origin,evolution and distribution of the Chinese genera is discussed mainly, and the distribution of the whole subfamily in the floristic regions of the world is also mentioned. Based on evolutionary trends of morphological characters, Spiraea L. is considered as the most primitive genus in the deciduous group of subfam. Spiraeoideae, from which some genera are been derived, the systematic position and evolutionary relationships between different genera are elucidated in this paper. Through the analysis on the geographical distribution of the genera in China, the areal types may be divided as follows: (1) North Temperate Type: Spiraea, Physocarpus, Aruncus. (2) East Asian and North American Disjunct Type: Sorbaria. (3) Mediterranean, West Asian (or Central Asia) and East Asian Type: Sibiraea. (4) Temperate Asian Type: Exochorda.(5) East Asian Type: (a) Sino Himalayan Distribution: Neillia; (b) Sino Japan Distribution: Stephanandra. After analysis of the distribution of subfam. Spiraeoideae in the world, it is shown that the Eastern Asiatic Region, being the richest in genera, species and endemic species of the world,is not only the center of distribution and differentiation,but also an important region for occurrence and development of some deciduous genera of this subfamily, while in North America, the Madrean Region and Rocky Mountain Region, genera, species and endemic species are abundant, which indicates that the western part of North America is also the distribution center of this subfamily at the present, but it may be the secondary center of distribution. It can be seen that the relatively primitive and evergreen g enera, i.e. Quillaja and Kageneckia, are now confined to South America. The fact implies that the South America may be the region for early differentiation and development of the evergreen genera in Subfam. Spiraeoideae. The analysis of Chinese plants has shown that China has the most members of the subfamily in Eastern Asiatic Region, with eight genera, 82 species and 62 endemic species and that the maximum concentration is in western Sichuan, northwestern Yunnan and their adjacent areas. It is very obvious that the center of distribution and diversity of Subfam. Spiraeoideae in China lies in the Hengduan Mountain Region of Sino Himalayan Forest Subkingdom and the western part of Sino Japan Forest Subkingdom, where may be the birthplace of some genera in China. It may be considered that the deciduous genera of Subfam. Spiraeoideae might have originated in Laurasia.According to the fossil records, the time of origin of Subfam.Spiraeoideae dates back to the Lower Cretaceous.     

Pollen-expressed F-box gene family and mechanism of S-RNase-based gametophytic self-incompatibility (GSI) in Rosaceae

Many species of Rosaceae, Solanaceae, and Plantaginaceae exhibit S-RNase-based self-incompatibility (SI) in which pistil-part specificity is controlled by S locus-encoded ribonuclease (S-RNase). Although recent findings revealed that S locus-encoded F-box protein, SLF/SFB, determines pollen-part specificity, how these pistil- and pollen-part S locus products interact in vivo and elicit the SI reaction is largely unclear. Furthermore, genetic studies suggested that pollen S function can differ among species. In Solanaceae and the rosaceous subfamily Maloideae (e.g., apple and pear), the coexistence of two different pollen S alleles in a pollen breaks down SI of the pollen, a phenomenon known as competitive interaction. However, competitive interaction seems not to occur in the subfamily Prunoideae (e.g., cherry and almond) of Rosaceae. Furthermore, the effect of the deletion of pollen S seems to vary among taxa. This review focuses on the potential differences in pollen-part function between subfamilies of Rosaceae, Maloideae, and Prunoideae, and discusses implications for the mechanistic divergence of the S-RNase-based SI.     

NUCLEAR DNA CONTENT VARIATION WITHIN THE ROSACEAE

Nuclear DNA content has been estimated using flow cytometry for 17 species and eight cultivars of Malus and for 44 species of 29 other genera within the Rosaceae. Compared to other angiosperms, diploid genome sizes vary little within the family Rosaceae and within the genus Malus. C-values of genera within the subfamilies Spiraeoideae and Rosoideae are among the smallest of flowering plants thus far reported. In general, the Maloideae have the largest diploid genomes of the family, consistent with their higher chromosome numbers and presumed polyploid origin.     

Phylogenetic relationships in Rosaceae inferred from chloroplast matK and trnL-trnF nucleotide sequence data

 Phylogenetic relationships in Rosaceae were studied using parsimony analysis of nucleotide sequence data from two regions of the chloroplast genome, the matK gene and the trnL-trnF region. As in a previously published phylogeny of Rosaceae based upon rbcL sequences, monophyletic groups were resolved that correspond, with some modifications, to subfamilies Maloideae and Rosoideae, but Spiraeoideae were polyphyletic. Three main lineages appear to have diverged early in the evolution of the family: 1) Rosoideae sensu stricto, including taxa with a base chromosome number of 7 (occasionally 8); 2) actinorhizal Rosaceae, a group of taxa that engage in symbiotic nitrogen fixation; and 3) the rest of the family. The spiraeoid genus Gillenia, not included in the rbcL study, was strongly supported as the sister taxon to Maloideae sensu lato. A New World origin of Maloideae is suggested. The position of the economically important genus Prunus and the status of subfamily Amygdaloideae remain unresolved. Received February 27, 2001 Accepted October 11, 2001     

中国蔷薇科绣线菊亚科的演化、分布——兼述世界绣线菊亚科植物的分布

绣线菊亚科是蔷薇科最原始的亚科,共有22属260余种, 包括常绿和落叶两大类群,前者是 原始类型。我国有8属100种,全都为落叶性。本文着重讨论中国各属的起源、演化和分布等 ,同时也概述全亚科植物在世界各植物区的分布等问题。绣线菊属Spiraea是该亚科落叶类群中最原始的属,它在早期发生趋异进化,衍生出形态各异而亲缘关系密切 的不同属,本文阐明了中国各属的系统位置和属间的亲缘关系。通过对我国各属地理分布的 分析对比,属的分布区可归纳为5个类型。对全球绣线菊亚科植物在世界各植物区中的属、种数统计表明,东亚区有8属105种,其中有96个特有种,是该亚科植物分布最多而又最集中 地区,具有在系统发育上处于各主要演化阶段的落叶类型,因此,东亚区是全球绣线菊亚科植 物的现代分布和分化中心,也是落叶类群发生和发展的关键地区。在北美洲,从马德雷区至落基山区一带分布着11属46种,均为特有种,显然北美洲西部也是该亚科植物的现代分布中心,但可能是第二分布中心。南美洲至今保存2个较古老的常绿属,即Quillaja和K ageneckia,基于此,南美洲可能是绣线菊亚科某些常绿属早期分化和发展的关键地区 。中国绣线菊亚科植物在东亚区占绝对优势,有8属82种,其中有62个特有种,分别占该区属 、种和 特有种数的100%、82%、和65%, 这些类群分布最密集地区是在中国喜马拉雅森林植物亚区 中的横断山脉地区和中国日本森林植物亚区的西部,这一带是中国绣线菊亚科的现代分布和多样性中心,很可能是某些属的发源地。由此看来,绣线菊亚科的落叶属可能起源于劳亚古陆。据化石记载,该亚科植物的起源时间可以追溯到白垩纪早白垩世。     

The phylogeny of the Rosaceae

KALKMAN, C., 1988. The phylogemy of the Rosaceae. A phylogenetic (cladistic) analysis of Rosaceae (excluding Chrysobalanaceae and Neuradaceae) is presented, based on the postulated direction of evolution in 14 morphological characters. Tribes or smaller groups, considered to be holophyletic, are taken as operational units. Three possible cladograms, made by hand, are presented and discussed. One of them is, within the limits of the method, selected as the most plausible image of real history, but this cladogram is not fully resolved and contains much homoplasy. Also presented is a fourth cladogram, produced by computer (CAFCA program); it is of about the same quality.
It is not justified to base drastic alterations in current classification on the weak phylogenetic hypothesis. For the time being it seems better not to recognize any subfamilies, but only a number of tribes.
It is hypothesized that the family originated in West Gondwana. A diagram is presented in which the most plausible cladogram is combined with the present distribution, clarifying the postulated routes of migration.
The sistergroup of Rosaceae is far from evident. The Cunoniaceae are considered to be the most plausible choice.     

The Chloroplast Genome of Cerasus Campanulata Diverges from Other Prunoideae Genomes

Cerasus Campanulata is one of several species belonging to the Prunoideae focke, a subfamily of the flowering plant Rosaceae. We investigated the details of its chloroplast genome which may reveal its genus independent of morphological determination. Here, we determined the complete chloroplast (cp) genome sequence of C. campanulata and performed sequence analysis to reveal the presence of 18 forward repeats, 20 palindrome repeats, 2 complement repeats, 4 reverse repeats and 93 simple sequence repeats (SSRs). We additionally performed a comparative study of C. campanulata and seven other Prunoideae focke species. Then, maximum parsimony (MP) and maximum likelihood (ML) phylogenetic analyses were carried out in the little part of Rosaceae, respectively. The results strongly support a position of C. campanulata as a member of the Cerasus in the Rosaceae family. Moreover, the complete cp genome can be used for plant phylogenetic and evolutionary studies that will provide insight into the degree of gene conservation.     

Phytoalexin induction in the sapwood of plants of the Maloideae (Rosaceae): Biphenyls or dibenzofurans

Following fungal inoculation or natural infection, five biphenyl phytoalexins (aucuparin and its 2′ and 4′ oxygenated derivatives) were induced variously in the sapwood of Aronia, Chaenomeles, Eriobotrya, Malus(three spp.) and of Sorbus aucuparia. By contrast, 14 dibenzofuran phytoalexins were induced variously in sapwood of Cotoneaster (7 spp.), Crateagus, Cydonia, Mespilus, Photinia, Pseudocydonia, Pyracantha, Pyrus and two Sorbus spp. (S. chamaemespilum and S. domestica). These were five cotonefurans, three eriobofurans, five pyrufurans and a 2,3,4,7,8-pentaoxygenated dibenzofuran trimethyl ether. No plant has yet been found to produce both types of phytoalexin, although o-hydroxybiphenyls are theoretically precursors of the dibenzofurans. The ability to synthesize either biphenyls or dibenzofurans appears to be genus-specific, except in the case of Sorbus. In 18 of the 38 species tested, these phytoalexins were accompanied by constitutive antifungal phenolics, most of which appeared to be released from bound (glycosidic) forms during the infection process. These were identified variously as hydroquinone, p-hydroxyacetophenone, acetovanillone, 5,7-dihydroxychromone, chrysin, sakuranetin and naringenin. Woody members of the subfamilies Prunoideae and Spiraeoideae failed to yield any phytoalexins on induction, but did contain constitutive antifungal compounds. The limited frequency of the phytoalexin response within the family as a whole is considered in relation to the accumulation of constitutive antifungal agents in these plants.     

The systematics and zoogeography of Spinicaudinae and Meteterakinae (Heterakoidea: Nematoda) parasitic in reptiles and amphibians

Summary The early evolution and zoogeography of the superfamily Heterakoidea is considered from a detailed analysis of the the primitive representatives in amphibians and reptiles (subfamilies Meteterakinae and Spinicaudinae). Meteterakinae have a disjunct distribution (Oriental, Neotropical) suggesting an ancient relict status. Spinicaudinae have a cosmopolitan distribution with the greatest diversity in the southern continents. Distributions of the various genera were clearly determined by continental drift. Both groups occur in a wide variety of frogs, lizards, primitive snakes and Rhynchocephalia. The principal host groups evolved at least as far back as the Cretaceous, suggesting the Heterakoidea are similarly ancient.     

The origin of the apple subfamily (Maloideae; Rosaceae) is clarified by DNA sequence data from duplicated GBSSI genes

For 70 yr the leading hypothesis for the origin of the Maloideae has involved wide hybridization between ancestors of two other subfamilies. The basis of this hypothesis is that Maloideae have a base chromosome number of 17, whereas other Rosaceae are mostly x = 7, 8, or 9. To investigate this hypothesis we cloned and sequenced approximately 1.8 kilobases from the 5' portion of granule-bound starch synthase (GBSSI, or waxy) genes for 89 clones from 32 Rosaceae genera. Previous studies demonstrate the presence of two copies in all Rosaceae (GBSSI-1 and GBSSI-2) and four in Maloideae (GBSSI-1A, GBSSI-1B, GBSSI-2A, and GBSSI-2B). Parsimony and maximum likelihood analyses nest Gillenia, a genus of the southeastern United States with a base chromosome number of 9, within either Maloideae GBSSI-1 or GBSSI-2. Monophyly of Maloideae plus Gillenia is well supported by bootstrap values, loss of the sixth intron in all GBSSI-1 sequences, intron alignability between genera, and numerous nonmolecular characters. Our results falsify the wide-hybridization hypothesis and are consistent with a polyploid origin involving only members of a lineage that contained the ancestors of Gillenia. Under this hypothesis, the subfamily originated in North America, and the high Maloideae chromosome number arose via aneuploidy from x = 18.     

Origin and Evolution of Rosaceae

Rosaceae. consisting of about 126 genera and 3200 species, is widely distributed in warm temperate and subtropical regions of the Northern Hemisphere, while more than half of the genera are Asiatic and more then 80% of the total number of Asiatic occur in China (Table 1). In this paper, the origin and evolution of Chinese genera is discussed mainly. The principal tendency of the whole family is also described from the point of view of evolution. First of all, the systematic position of Rosaceae in Angiospermae is reviewed. According to the records of paleobotany, rosaceous plants occurred first in the Tertiary, from the early period of Eocene (genera such as Spiraea and Prunus) to the late period of Miocene (e.g. Crataegus, Malus amd Rosa). They have quite a long history in geological data. Where has this big and old family originated and what steps does it stand in the long course of evolution of flowering plants? There are several opinions and explanations by different authors. In this paper, a general survey of the six prevailing classical systems (Table 2) is made to give a brief idea of the position of this family in the Angiospermae and of the relationships between the subfamilies and also the relationships between different genera in each subfamily. At the end of this paper, an attempt is made to analyse and sum up the major evolutionary tendency of the whole family. As generally condidered, Rosaceae originated from Magnoliales, and woody plants of the family still hold a dominant position. For instance, subfamily Spiraeoideae consists of only one herbaceous genus (i.e., Aruncus) and subfamily Rosoideae only a few herbaceous genera. All of these herbaceous genera are derived from the closely related woody genera of the same subfamily. In the course of evolution of Angiospermae, Rosaceae stands at the initial to the middle stages of development. All parts of plant body in this family are at the chang ing and developing stages, with carpels, fruits and inflorescences being the most active. The primitive types in this family, such as the members of subfamily Spiraeoideae, usually have 5 and free carpels, the number of which are either reduced to 2-1 or increased to 10-numerous. They have different levels of union and are either completely free from each other or coherent at base. The carpels usually occur on the upper part of the receptacle, because the shapes of receptacle are variable, sometimes disk-shaped, cupshaped, tube-shaped or even bottle-shaped. In the last case carpels grow inside the receptacle. Thus the position of carpels has changed from superior to inferior through halfsuperior. In accordance with the development of the carpels, various kinds of fruits are produced. The primitive types of fruit are follicles, with dry, dehiscent carpels opened along different sutures. The next step, the carpels have developed into an indehiscent, I-celled and l-seeded fruit, the so-caned achene. In different genera, the achenes have different coat types and appendages to facilitate dispersing the seeds. Some of the achenes grow upon the fleshy receptacle (like strawberry) and some of them inside the fleshy receptacle (like rose). Sometimes a few carpels are united with the receptacle and develop into a pome (like apple and pear). Another direction of the fruit development is the single carpel with fleshy exocarp and mesocarp, and a bony endocarp, then becoming a drupe (like peach and plum). In addition to fleshy receptacle of thickened fruit coats, they usually have showy colour, fragrant smell and also plenty of sugars, acids, vitamins, etc. which are edible and attract animals and human beings to assist the dispersion of seeds. In this family, there are various types of flower arrangements, both indefinite inflorescences including raceme, umbel, corymb and panicle, and the definite inflorescence, such as solitary flower, cyme and compound cyme. In the evolution course, they tend to change mostly from multiflowered compound inflorescence towards few-flowered simple inflorescence, and finally becoming a solitary flower: simultaneously with the decreasing of number of flowers on the inflorescence, the increasing of size of petals, which become very showy for attraction of insects so as to guarantee pollination and fertilization of the plants concerned. Another tendency, if the bisexual flowers change to unisexual, either monoecious- or dioecious-polygamous, then they form a dense spike which is beneficial to cross pollination. The abundance, diversity, and wide range of distribution of the species and genera of Rosaceae are considered mainly resulted from their highly developed reproductive organs.     

Comments on the Systematics and Classification of the Beavers (Rodentia, Castoridae)

The systematics of the beavers (Castoridae) are reviewed and definitions are presented for each subfamilial group. Four subfamilies are recognized: primitive Agnotocastorinae (divided into two tribes, Agnotocastorini and Anchitheriomyini); burrowing beavers, Palaeocastorinae; giant beavers, Castoroidinae (containing two tribes, Castoroidini and Trogontheriini); and the Castorinae. The agnotocastorines are viewed as the ancestral group for all later subfamilies. The Palaeocastorinae is viewed as a side-branch, not ancestral or closely related to any of the later subfamilies. The Castorinae and Castoroidinae may represent a distinct clade united by dental features.     

Transferability of Newly Developed Pear SSR Markers to Other Rosaceae Species

A set of 120 simple sequence repeats (SSRs) was developed from the newly assembled pear sequence and evaluated for polymorphisms in seven genotypes of pear from different genetic backgrounds. Of these, 67 (55.8 %) primer pairs produced polymorphic amplifications. Together, the 67 SSRs detected 277 alleles with an average of 4.13 per locus. Sequencing of the amplification products from randomly picked loci NAUPy31a and NAUpy53a verified the presence of the SSR loci. When the 67 primer pairs were tested on 96 individual members of eight species in the Rosaceae family, 61.2 % (41/67) of the tested SSRs successfully amplified a PCR product in at least one of the Rosaceae genera. The transferability from pear to different species varied from 58.2 % (apple) to 11.9 % (cherry). The ratio of transferability also reflected the closer relationships within Maloideae over Prunoideae. Two pear SSR markers, NAUpy43c and NAUpy55k, could distinguish the 20 different apple genotypes thoroughly, and UPGMA cluster analysis grouped them into three groups at the similarity level of 0.56. The high level of polymorphism and good transferability of pear SSRs to Rosaceae species indicate their promise for application to future molecular screening, map construction, and comparative genomic studies among pears and other Rosaceae species.