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Sesleria (Poaceae) is a species-rich, taxonomically difficult genus due to high morpho-anatomical variability and weak differentiation of many species. It is distributed throughout western Eurasia and North Africa with highest taxonomic diversity on the Balkan Peninsula. Of the more than 40 species only two are diploid, all others are tetra- to dodecaploid, and many species comprise several ploidy cytotypes. We sequenced the plastid trnL-ndhF region and produced amplified fragment length polymorphisms (AFLPs) from a comprehensive, ploidy-cytotyped sampling including 292 populations, and produced nuclear ribosomal internal transcribed spacer (ITS) sequences for a subsample. Our first aim was to determine the relationships among Sesleria and putatively closely related genera. Further, we explored whether diploid S. sphaerocephala and S. ovata should be treated as separate genera Sesleriella and Psilathera as proposed previously, or rather included in Sesleria, following most recent Floras. Finally, we tested previous hypotheses of infrageneric classifications. In the ITS phylogeny tetra- to dodecaploid Sesleria s.str. grouped with diploid S. ovata whereas diploid S. sphaerocephala was more distantly related. In contrast, in the plastid phylogeny Sesleria s.str. grouped with S. sphaerocephala, whereas S. ovata was sister to Echinaria. This suggests an allopolyploid origin of Sesleria s.str. with S. sphaerocephala acting as maternal and S. ovata as paternal species. The lack of monophyly of Sesleria s.l. thus supports the recognition of S. ovata and S. sphaerocephala as separate genera Psilathera and Sesleriella. Their segregation, which is also supported by morphology, increases the number of angiosperm genera endemic to the European Alps from three to five. In congruence with the plastid sequences, AFLPs resolved the traditionally recognized sections (sect. Argenteae, sect. Sesleria) as non-overlapping clusters and identified S. vaginalis as a probably recently evolved intersectional hybrid. Within the two sections, several informal species groups could be recognized, which show limited congruence with those proposed in the most comprehensive taxonomic treatment of the genus. From an evolutionary point of view it is obvious that ancient as well as recent hybridization coupled with polyploidisation have played a crucial role in diversification within Sesleria. [ABSTRACT FROM AUTHOR]

Leaf epidermis has been used as character in taxonomy of Poaceae family since the 1930s. The purpose of present study was to determine leaf epidermal features helpful in distinguishing two species of Sesleria genus – Sesleria heufleriana Schur and Sesleria uliginosa Opiz.Both the abaxial and the adaxial epidermis have been examinated for each species.So both examined species have Festucoid type of epidermis, but differences of some epidermal features exist at the species level. This include variation in number and size of epidermal cells and distribution patterns of stomata.

The genus Chlorionidea Low until now contained two species: C. flava Low and C. bromi Emeljanov. Recently we discovered two new species of this genus in Italy, which we describe in this paper as C. apenninica sp. nov. and C. sibillinica sp. nov. For all four Chlorionidea taxa we provide descriptions and an identification key. Details of male and female genitalia, aspects of head morphology and the fifth instar nymph of C. sibillinica are shown. In addition we discuss phylogenetic relationships between the four taxa. In three of the four species anti-symmetry in male genitalia is observed. We discuss this phenomenon and compare similar cases in other Delphacidae. Finally we summarize the available data on life cycle, food plants and geographical distribution of Chlorionidea species. [ABSTRACT FROM AUTHOR]

A taxonomic study of the Sesleria juncifolia complex in the Italian Peninsula is presented, with a focus on southern Italian populations here named as Sesleria calabrica (DEYL) DI PIETRO comb. nov. et stat. nov. Karyological, morphological and anatomical characters were used for comparative analyses with populations of closely related species, such as S. juncifolia SUFFREN and Sesleria apennina UJHELYI occurring in the Italian Peninsula. Multivariate and univariate morphometric analyses, and qualitative morphological characters showed a distinct position of S. calabrica. Populations of S. calabrica differ in respect to various morphological characters of leaf and spikelet, such as the glume, lemma and palea length, stem length, the leaf sheath, leaf width, leaf thickness, and the total number of vascular bundles. Furthermore, previous karyological studies demonstrated that all the populations of both S. juncifolia and S. apennina examined are octoploid (2n=8x=56), whereas S. calabrica was found to be dodecaploid (2n=12x=84). S. calabrica is strictly confined to the Pollino massif and the Orsomarso mountains in southern Italy, which represent the southernmost limit of the Sesleria juncifolia complex distribution area both in Italy and in Europe. In addition to S. juncifolia and S. calabrica, the recognition of S. apennina as a taxon distinct from S. juncifolia is supported, at least for the area of the Apuan Alps. [ABSTRACT FROM AUTHOR]

Abstract: Plant communities on plots with different metal pollution levels were compared in a field study in order to select the most suitable plant species for the direction of secondary succession toward the targeted grassland vegetation. The vegetational succession showed a gradual increase in plant cover and the number of plant species on the less polluted locations. Two predominant grass species Calamagrostis varia and Sesleria caerulea were selected for phytostabilisation, but a severely reduced seed germination capacity obstructed their use in practice. The mycorrhizal succession showed a gradual replacement of non-mycorrhizal with mycorrhizal plant species. Similar levels of arbuscular mycorrhizal colonisation of a particular plant species may be developed within each growing season regardless of the levels of pollution, with the exception of vesicle/intraradical spore formation. The results suggest that lower overall mycorrhizal colonisation levels and increased vesicle/spore formation may be a part of a mycorrhizal strategy at the most polluted locations. [Copyright &y& Elsevier]

Some closely related members of the monocotyledonous families Alismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae and Araceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate ('ambophilous' or 'amphiphilous') monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly 'dry' and powdery pollen of anemophilous plants always contains a variable amount of 'inactive' pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout. [ABSTRACT FROM AUTHOR]