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1.
Populations of Arenaria uniflora exhibit intraspecific variation in floral size and degree of protandry in association with the evolution of self-pollination. Heterochrony, or a simple change in the absolute timing or rate of developmental events, is proposed as the evolutionary mechanism underlying the origin of the small, self-pollinating flowers from their large, outcrossing progenitors. Inflorescence growth in two autogamous populations and their related outcrossing progenitors was studied to provide the temporal data necessary for testing the hypothesis of heterochrony. All four races showed significant variation in the growth and mature length of inflorescence organs. Inflorescences of selfing races were smaller, and had slower relative growth rates and a two-fold increase in the plastochron relative to outcrossing populations. The large-flowered races were both significantly protandrous. A more detailed growth analysis of flower development in two races indicated that the selfing flowers develop at a slower rate and for a longer duration relative to outcrossing flowers. The implications of these temporal changes in floral ontogeny for the heterochronic origin of self-pollinating floral forms are considered.  相似文献   

2.
Genomic libraries of Arenaria grandiflora enriched for di- and trinucleotide repeats were used for the development of novel microsatellite markers. The subset of 13 polymorphic markers was characterized on 40 individuals of A. grandiflora originating from lowland locations in France. The loci amplified 3 to 10 alleles per locus and expected heterozygosities ranged from 0.46 to 0.83. The newly developed markers will be used for population genetic studies and for assessing genetic composition of a restoration experiment of lowland A. grandiflora populations that are protected in France.  相似文献   

3.
GOYDER, D. J., 1987. A revision of Arenaria section Plinthine (Coryophyllaceae). The systematics of Arenaria section Plinthine are reviewed and a classification is presented, based on detailed field and herbarium studies. Members of the section are found on the mountains of SW Europe and N Africa. Seven taxa are recognized within five species: A. alfacarensis, A. tetraquetra subsp. tetraquetra, A. tetraquetra subsp. amabilis, A. armerina, A. aggregata subsp. aggregata, A. aggregata subsp. erinacea , and A. querioides. Arenaria armerina and A. aggregata subsp. erinacea are extremely polymorphic and include minor morphological variants which have been treated as separate species in previous systematic treatments of the group.  相似文献   

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To further investigate the cyclopeptldes of the Caryophyllaceae family, two new cyclopeptldes, named Arenarlphilin E (compound 1) and Arenariphilin F (compound 2), were obtained from Arenaria oreophUe J. D. Hooker using some Isolation methods, e. g. normal and reverse silica gel. By detailed spectroscopic analysis, such as FAB^+-MS, 1 D NMR, 2D NMR, the structures of Arenariphilin E (compound 1) and Arenariphilln F (compound 2) were determined as cyclo(lle^1-Gly-Val^1-Ala-Leu-lle^3-lle^2-Val^2-Pro) and cyclo(Pro^2-Pro^1-Gly^2-lle-Val-Leu-Gly^1-AiaThr- Gly^3), respectively.  相似文献   

6.
Comments on the taxonomic treatment of Arenaria section Plinthine (Caryophyllaceae) by D. J.Goyder. Comments are given on the taxonomic treatment of Arenaria section Plinthine presented by D. J.Goyder in a revision of this group recently published in the Botanical Journal of the Linnean Society, 97(1): 9–32.  相似文献   

7.
对横断山脉地区青藏雪灵芝(Arenaria roborowskii)进行了核形态学研究。核型公式为2n=2x=22=22m,核型不对称性为1A型。间期核为复杂染色体型,前期染色体为中间型。  相似文献   

8.
Fabio Conti 《Plant biosystems》2013,147(2):191-194
ABSTRACT

A new Minuartia was discovered in Cilento (S. Italy). The species described here as M. moraldoi belongs to the ser. Graminifoliae.  相似文献   

9.
The factors responsible for the patterns of niche differentiation and narrow endemism have rarely been investigated in annual Mediterranean plants. This topic was addressed here by performing comparative studies on realized niches, regional occupancy, global biogeographical distribution and seed traits of a set of Arenaria (Caryophyllaceae) species inhabiting southern Provence (SE France), focusing in particular on Arenaria provincialis, a narrow endemic restricted to the hills and modest calcareous mountains around the city of Marseille. Field studies were carried out from 2008 to 2009 at 624 sites in the limestone mountains where Arenaria species are likely to occur. The Arenaria species occurring in southern Provence vary greatly in their patterns of regional occupancy and their biogeographical distribution. Multivariate analysis of the realized niche showed that they have some similar limiting environmental factors in common, but they do not all occupy the same habitats. Studies on the fruits and seeds showed that the endemic A. provincialis has a larger seed than its congeners and a capsule that remains closed and falls from the plant at maturity. This well-differentiated diaspore specific to A. provincialis may be responsible for the limited dispersal capacity of this species. Phylogenetic analyses showed that A. provincialis is not closely related to the other taxa inhabiting southern Provence, but rather to Arenaria occurring in highland areas in the south of France. The restricted pattern of distribution of A. provincialis is probably due to the past isolation event from which it originated and to its limited dispersal capacity, rather than resulting from its ecological niche range.  相似文献   

10.
The new taxonMoehringia intricata subsp.giennensis, from the calcareous mountains of the south-eastern Iberian Peninsula is described. A comparative morphological study with regard to the most closely related taxa, contributes information of leaf anatomy, seed and pollen morphology, ecology and distribution.  相似文献   

11.
We report on the isolation and characterization of eight microsatellite markers from enriched libraries for Arenaria nevadensis, one of the most critically endangered plant species in the Iberian Peninsula. These are the first microsatellite loci reported for Arenaria species. The number of alleles ranged from two to eight, and the expected heterozygosity from 0.067 to 0.873. These markers will be useful for characterizing the genetic diversity in A. nevadensis and understanding its population structure, and will provide important genetic data for the conservation and recovery of this species.  相似文献   

12.
Heliosperma oliverae Niketić & Stevanović is described from Mt. Prokletije in south-west Serbia and north-east Montenegro, together with an estimation of its ecological preferences and International Union for Conservation of Nature and Natural Resources (IUCN) threat status. A map and illustration are provided. It is compared with seven closely related Balkan endemic taxa: H. macranthum Panić, H. retzdorffianum K. Malý, H. tommasinii Vis., H. insulare Trinajstić, H. chromodontum (Boiss. & Reuter) Juratzka, H. intonsum (Greuter & Melzh.) Niketić & Stevanović, and H. nikolicii (Seliger & T. Wraber) Niketić & Stevanović. An amended key to species and a table showing differences from the related Balkan taxa are also provided.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 55–63.  相似文献   

13.
Arenaria bertolonii Fiori & Paol. is an orophyte and endemic European species of Italy and France. The name Stellaria saxifraga Bertol. (basionym of A. bertolonii) is typified on a herbarium specimen kept in BOLO. Infraspecific variability of the species is discussed and a comparison with related taxa included in the Subg. Arenaria was made on the basis of morphological analyses and chorological and cytological data. At the sectional level, the results show that A. bertolonii is clearly separate from the morphological and chorological points of view, thus supporting the proposal for a new monotypic section (Sect. Italiae Iamonico) of central Mediterranean species. The analysis of infraspecific variability instead highlighted overlapping morphological characteristics; the distribution areas of the infraspecific taxa are sympatric and any cytological difference is lacking, thus pointing to a synonymization of the names. Notes on the ecology and distribution of A. bertolonii are also provided.  相似文献   

14.
Karyotypic characters, mitotic metaphase chromosomes, monoploid idiograms and karyograms of Minuartia anatolica (Boiss.) Woronow var. phrygia (Bornm.) McNeill, Minuartia anatolica (Boiss.) Woronow var. scleranthoides (Boiss. & Noe) McNeill, Minuartia corymbulosa (Boiss. & Balansa) McNeill var. gypsophilloides McNeill and Minuartia aksoyi M.Koç & Hamzao?lu were investigated for the first time. Analysis of somatic metaphases showed that the chromosome numbers and the formulas of these taxa were 2n = 24 = 14m + 6sm + 4st for Minuartia anatolica var. phrygia, 2n = 14 = 6m + 8sm for Minuartia anatolica var. scleranthoides, 2n = 14 = 6m + 4sm + 4st for Minuartia corymbulosa var. gypsophilloides and 2n = 30 = 14m + 10sm + 6st for Minuartia aksoyi. No satellites were observed in the karyotypes of these taxa. Karyotype asymmetry was estimated by many different methods, namely the Stebbins classification, the karyotype asymmetry index (As K %), the total form percent (TF %), the Rec and Syi indices, the intrachromosomal asymmetry index (A1) and interchromosomal asymmetry index (A2), the dispersion index (DI), the degree of asymmetry of karyotype (A index) and the asymmetry index (AI).  相似文献   

15.
Silene thebana Orph. exBoiss. is transferred as a subspecies toS. fabaria (L.)Sm., resulting in the new combinationS. fabaria (L.)Sm. subsp.thebana (Orph. exBoiss.)Melzh. The chromosome count of 2n = 24 is recorded for the first time for this taxon.Dedicated to Prof. DrK. H. Rechinger on the occasion of his 80th birthday, 16th October 1986.  相似文献   

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17.
Gypsophila huashanensis Y. W. Tsui et D. Q. Lu and G. spinosa D. Q. Lu (Caryophyllaceae) are described as new from China.  相似文献   

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20.
The genetic architecture of floral traits involved in the evolution of self-pollination provides a window into past processes of mating system divergence. In this study, we use two generations of crosses between highly selfing and predominantly outcrossing populations of Arenaria uniflora (Caryophyllaceae) to determine the minimum number, average dominance relationships, and pleiotropic effects of genetic factors involved in floral divergence. Comparison of the F1 and F2 phenotypic means with the expectations of a completely additive model of gene action revealed a primarily additive genetic basis for floral characters associated with mating system variation. The exception was flower life span, which showed partial dominance of the outcrosser phenology. In contrast to similarly divergent species, the substantial differences in flower size between these A. uniflora populations appear to involve relatively few genes of large effect (minimum number of effective factors = 2.2 +/- 2.8 SE). In addition, correlations among traits in the F2 generation indicate that pleiotropy may be an important feature of the genetic architecture of floral evolution in A. uniflora. The evolution of selfing via major modifiers of floral morphology is consistent with other evidence for ecological selection for preemptive self-pollination in A. uniflora. Analyses of the genetic basis of autonomous selfing were complicated by hybrid breakdown in both F1 and F2 generations. Only F1 hybrids showed reductions in female fertility, but about 30% of F1 and F2 hybrids exhibited partial or complete male sterility. Male sterile flowers were characterized by short stamens, reduced petals, and a lack of protandry, as well as indehiscent anthers. This morphological breakdown mimics environmental disruptions of floral development and may result from novel genic interactions in hybrids.  相似文献   

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