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The identity of the original material of Juncus kochii F. W. Schultz (Juncaceae) is discussed. The taxon at present is best regarded as Juncus bulbosus L. subsp. kochii (F. W. Schultz) Reichg. The relevant literature (protologue and references therein) was searched and details of all original elements were compiled. Nomenclatural and taxonomic remarks are given. Juncus welwitschii Hochst. ex Steud. is here excluded as a synonym of Juncus bulbosus subsp. kochii.
The identity of the potential original material of Juncus kochii is discussed. The taxon at present is best regarded as Juncus bulbosus L. subsp. kochii (F.W. Schultz) Reichg. The relevant literature (protologue and references therein) was searched and details of all residual original elements were compiled. Taxonomic remarks are given. The herbarium material from the environs of Bitche (Moselle, Lorraine) and Gérardmer (Vosges, Lorraine) – both in France, has been rejected as useless for typification of J. kochii (because of taxonomic reasons), though it was listed both in the protologue and also as indirect references therein Schultz’s earlier publications.
The first localities of Juncus bulbosus (Juncaceae) for South America (Chile) and for the whole south-western part of the world (S latitude and E longitude) are described, including precise geographical location and climatic conditions. General remarks on the invasiveness of the species and on the possibility of finding it in other parts of the world are given. The distribution of the species world-wide requires further studies, since the bulbous rush has become an invasive plant in areas where it did not occur before.
A long-term callus culture from Luzula luzuloides leaf meristem subcultured for over one year was examined cytologically. In the control material most of the mitotic cells (95.97%) represented diploid level and standard chromosomes in terms of length (2n = 12AL). Aneuploidy occurred with low frequency (4.03%), with somatic chromosome numbers 2n = 13, 14 resulting from partial agmatoploidy. Karyotype analysis of control material showed differences in chromosome length ranging from 4.94 µm to 3.19 µm in prometaphase, 3.54 µm to 2.54 µm in mid metaphase, and 2.81 µm to 1.88 µm in late metaphase. Callus cells exhibited a wide range of chromosome number variation (2n = 7-48), although a high percentage of cells (61.39%) represented the standard karyotype (2n = 12AL). Variability in chromosome number and karyotype structure was a consequence of chromosome fission (partial and total agmatoploidy), chromosome fusion (partial symploidy) as well as aneusomaty and polyploidy. There was no evident correlation between the frequency of structural and numerical chromosome variation and the duration of callus culture. The cells with modified karyotype appeared in particular collections.
A study of Gentiana cruciata L. (Gentianaceae), Gymnadenia conopsea (L.) R.Br. (Orchidaceae) and Luzula pedemontana Boiss. et Reut. (Juncaceae) showed differences in the number and characteristics of critical stages in ovule and seed development. The shared critical stages explain the general direction of the formation of reproductive structures and surrounding tissues. The taxon-specific critical stages may have different implications in a given species: they may (1) verify that the ovule belongs to a specific type, (2) indicate their lability in different taxa with the same ovule type, or (3) coincide in species with various ovule types.
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