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Apomixis is a form of asexual reproduction that consists in cloning through seeds. In Limonium (Plumbaginaceae) species present a pollen-stigma dimorphism linked to a sporophytic self-incompatibility system associated with sexual and/or apomictic reproductive modes. Previous work in other genera suggests that the emergence of apomixis is associated with hybridization and/or polyploidy. In this study, our goal was to test the ability of diploid and tetraploid species to hybridize and to evaluate the variate outcomes from these crosses. To achieve this, sexual diploid (L. nydeggeri, L. ovalifolium) and facultative apomict tetraploid (L. binervosum, L. dodartii) plants from cultivated material, previously cytogenetically and reproductively characterized, were used for experimental intra- and interspecific crosses. Genome sizes, ploidy levels and morphology were examined in the resulting progenies. Results showed a high production of viable seeds in particular in plants from tetraploid × diploid (heteroploid) crosses. In these crosses, some seedlings exhibited pleiocotyly (tricotyl, tetracotyl), while others showed polyembryony. In both homoploid (diploid × diploid) and heteroploid (tetraploid × diploid) crosses, most of the offspring plants were morphologically and in their ploidy similar to the female receiver, although some morphological abnormalities were found. Molecular progeny tests using the nrDNA ITS1-ITS2 sequence demonstrated an astounding range of diploid offspring plants originated from diploid × diploid crosses that were either genetically similar or distinct from parental plants. Although in intraspecific crosses most of the resulting progeny was diploid, one triploid plant was formed. Moreover, in homoploid interspecific crosses, neopolyploids (two tetraploid plants) were produced. Progeny plants from heteroploid crosses always showed nrDNA ITS1-ITS2 sequences identical to the parental plant used as female receiver. In conclusion, diploid homoploid crosses presented genetically diverse offspring arising from sexual reproduction. By contrast, heteroploid crosses generated clonal, maternal (apomictic) offspring. [ABSTRACT FROM AUTHOR]

The genus Limonium (sea lavenders) is characterized by various taxonomically challenging complexes with great karyological diversity, and chromosomes ranging in size from diminutive to large. In this biosystematic study, our goal was to investigate cytogenetic features of twelve sexual and asexual taxa in a particular part of their distribution range. Genome size, chromosome number variation, and other cytological features were investigated in a representative set of sea lavenders with distinct leaf venation, present in the coastal areas of the Iberian Peninsula, Morocco, France, and the Channel Islands. Flow cytometric genome size determinations were made in plants from natural populations. Cell and nuclear areas of epidermal cells, as well as, chromosome numbers and length were measured in plants from ex situ collections. Our findings revealed positive and significant correlations between holoploid genome size and cell size, nuclei area and chromosome total length. Tetraploid taxa with pinnately veined leaves had significant lower holoploid and monoploid genome sizes along with lower cell and nuclei areas and chromosome sizes than tetraploid taxa with parallel-veined leaves. The results obtained are discussed in the context of breeding relationships known or suspected among these taxa. In conclusion, our results provide a basis for future evolutionary studies, and support that pollen-stigma dimorphisms and genome size allied with chromosome counts might be important taxonomic traits in Limonium in apomictic/sexual groups. [ABSTRACT FROM AUTHOR]

The typification of the Linnaean name Statice limonium (≡Limonium vulgare) is discussed. Original material preserved at BM, LINN and UPS is heterogeneous and belongs to several species. The specimen at LINN (No. 395.3) is designated as the lectotype to preserve the current usage of the name. [ABSTRACT FROM AUTHOR]

The original circumscription and nomenclatural history of Statice minuta are discussed. The taxon nowadays indicated by this name is endemic to the Baleares (Spain, western Mediterranean), but neither the lectotype nor the Linnaean protologue support this usage. The paper clarifies the origin of this mistake and preludes to a formal proposal to conserve the name with a conserved type. [ABSTRACT FROM AUTHOR]

The halophytic shrub genus Limoniastrum has recently been recircumscribed to include only two Mediterranean-Saharan species, Limoniastrum monopetalum (L.) Boiss. (= Statice monopetala L.) and L. guyonianum Boiss. Protologues of both species are briefly discussed and lectotypes are designated using material at BM (Herb. Clifford) and G (Herb. Boissier). [ABSTRACT FROM AUTHOR]

Examines the taxonomic features of Myriolepsis, a novel genus segregated from Limonium. Comparison with other taxa in Plumbaginaceae; Morphological, karybiological and phytochemical characteristics of Myriolepis.

Provides information on Myriolepis (Plumbaginaceae). Use of the name Myriolepis at the sectional and subgeneric rank in Limonium; Meaning of Myriolepis; Ratification of the proposed name, Myriolimon, to replace the evidently illegitimate Myriolepis during the 17th International Botanical Congress in Vienna, Austria in July 2005.