Romanian Journal of Biology - Plant Biology
2006-2007, VOLUMES 51-52 (2007)
1. Expression of the phsp70(LP19)-GUS gene during pollen embryogenesis in transgenic plants of Datura innoxia
ELENA BADEA, OFELIA GOZIA
Fertile transgenic plants of Datura innoxia were obtained through transformation of leaf tissue with disarmed Agrobacterium tumefaciens strain LBA 4404, harbouring a binary vector containing a chimeric fusion between the pea hsp 70 (LP19) gene promoter and the GUS reporter gene, and in vitro regeneration via organogenesis. Molecular analysis of independent transformants confirmed the transgenic nature of plants regenerated by Agrobacterium – transformation. Quantitative and qualitative assay of fresh and cultivated anthers revealed a constitutive level of GUS activity in the anthers before cultivation. The enzyme activity decreased in the first 5 days and increased beginning with the 7th day of culture in both fresh and cold treated anthers. The increase of GUS activity could be correlated with the appearance of the first embryogenic structures. Our results suggest the involvement of HSP70 in embryogenesis as a normal part of developmental process, not associated with heat shock.
2. In vitro culture introduction for ex situ conservation of some rare plant species
IRINA HOLOBIUC, RODICA BL╬NDU
Many valuables plants species are nowadays threatened. To stop the continuous loss of plant biodiversity, the Global Strategy for Plant Conservation promotes the development of both in situ and ex situ conservation methods of rare and vulnerable species. While it is always preferable to conserve and to protect species and to preserve their native habitats, in many situations the ex situ conservation is also imposed. In our study, we have the main goal to introduce in vitro for ex situ conservation purpose of nine rare plants species from different families: Artemisia tscherneviana Bosser, Artemisia alba Turra, Doronicum orientale Hoffm. Doronicum carpaticum (Griseb.et Schenk) Nyman, Dianthus glacialis ssp. gelidus Schott, Nyman et Kotschy, Gentiana lutea L., Iris halophila Pallas, Primula halleri J.F. Gmelin, Veronica mulifida L. ssp. capsellicarpa (Dubovik) A. Jelen. In almost all species tested, there were induced in vitro tissue cultures and plants were regenerated successfully.
3. The influence of the static magnetic field (SMF) on some biochemical parameters in cellulolytic fungi Chaetomium globosum and Trichoderma viride cultivated on media supplemented with panification industrial wastes
ALEXANDRU MANOLIU, L├CR├MIOARA OPRICA, DORINA CREANG├
This paper presents the influence of the static magnetic field (SMF) on cellulases: (endo-1,4-β-glucanase – E.C. 184.108.40.206., cellobiohydrolase – E.C. 220.127.116.11. and β-glucosidase – E.C. 18.104.22.168.), peroxidase – E.C. 22.214.171.124. and catalase – E.C. 126.96.36.199. activity in cellulolytic fungi Chaetomium globosum and Trichoderma viride cultivated on media with waste from industry of panification. The activity of these enzymes was influenced both by the cellulolytic species studied and by the time of exposure to the static magnetic field (SMF).
4. Comparative anatomy of the vegetative organs of some Euphorbia species (Euphorbiaceae Juss.) from the Romanian flora
RAMONA CRINA GALE¬, CONSTANTIN TOMA
This article compares the (subterranean and aerial) vegetative organs anatomy of 19 Euphorbia species from the Romanian flora, focusing on identifying the constant and variable histo-anatomical characters. The root structure differed by the type of primary stele structure and the secondary xylem organization. The rhizome characters which best distinguished among perennial taxa were: the absence or the presence of a peridermis, the secondary xylem organization and the pith conformation. In the stem the best diagnostic characters were: the pattern of epidermis cells, the presence or the absence of trichomes, the cortex organization and the repartition mode of secondary conducting tissues. The foliar limb structure differed by the pattern of epidermis cells, the mesophyll organization and the localization of stomata. The constant histo-anatomical characters of the taxa taken into study were: laticifers in all the vegetative organs, cordons of periphloemic sclerenchymatous fibers in the stem, stomata of anisocytic and anomocytic-type in the foliar limb, libriform gelatinous fibers, tangentially collenchyma at the periphery of the stem cortex. Anomalous structures occurred in a few taxa.
5. Morphogenesis of apogamous sporophyte in Cyrtomium falcatum (L. Fil.) C. Presl. (Dryopteridaceae)
LILIANA CRISTINA SOARE, MARIN ANDREI
Formation of the apogamous sporophyte is initiated when the prothallus is two months old and cordate. The sporophyte is differentiated towards the apical, pitted region of the prothallus, in its median plane, on the inferior side. The apogamous tissue produces a kind of flattened crest with rounded margins, from which the first leaf of the sporophyte is differentiated. Later a second leaf is differentiated from the apogamous tissue, while between these two leaves the stem initial is differentiated. The stem apex is solely responsible for generating the growth axis of the postembryonic plant First stages of development of apogamous sporophytes in Cyrtomium falcatum don’t possess roots. Their absence is compensated by numerous rhizoids, generated by the prothallus around the apogamous sporophyte and, sometimes, on cells at the basis of the sporophyte. The first root of the apogamous sporophyte begins to differentiate from a tetrahedral initial cell after development of two or three leaves. In some cases on a prothallus two apogamous meristematic zones are differentiated, on either side.
6. Vegetative multiplication in Thamnolia vermicularis (Sw.) Schaer
MARIN ANDREI, MIOARA IACOB, GABRIELA PASCALE
As indicated in speciality literature Thamnolia vermicularis (Sw.) Schaer does not produce apothecia and multiplies exclusively vegetative; this prompted us to uncover the mechanism of this way of multiplication. We observed that the propagules involved in multiplication detach themselves in the shape of strips, due to the previous formation of a separation zone. We also observed that the thallus lobes are not hollow as asserted in the speciality literature, but contain a lax pseudodiaphragmatic plectenchyma, serving the same purpose as the diaphragmatic tissue in aeriferous canals of aquatic plants. Research will be continued.
7. Contributions to the study of saxicolous vegetation from Bicaz Gorges (Eastern Carpathians)
NICOLAE ¬TEFAN, CIPRIAN M┬NZU, C. MARDARI
In this paper we present a number of 12 saxicolous vegetal associations identified on the “Cheile Bicazului-Lacu Rosu-Hasmasul Mare” National Park territory. Among them we propose 3 new vegetal associations having the following provisional names: Valeriano (tripteris) – Polypodietum vulgare ass. nova, Galio (albi) – Teucrietum montani ass. nova and Melico (ciliatae) – Festucetum pallentis ass. nova.
8. The Hieracio transsylvanici - Abietetum (Borhidi 1971) Coldea 1991 association from the "Obcinele Bucovinei" territory
CIPRIAN M┬NZU, B. ¬URUBARU, TOADER CHIFU
The authors present the Hieracio transsylvanici – Abietetum association from the “Obcinele Bucovinei” territory, an association that has never been noted before in this area. At the same time, they would like to propose a coenotaxonomic framing of this association into the Abieti – Piceion alliance, Athyrio – Piceetalia order.
9. Flora and vegetation of the Natural Reserve "Zugreni Gorges" (Suceava County)
The vascular flora, along with all the vegetal communities growing in the Natural Reserve “Zugreni Gorges” (Suceava county), is presented in this paper. Also, there is the only place in the world where it grows a very strictly endemic plant species, namely Pietrosia levitomentosa (syn. Andryala levitomentosa). This species, accompanied by others, makes an endemic vegetal association, namely: ass. Sempervivo soboliferae- Andryaletum levitomentosae Seghedin 1985.
10. Characterization of two new habitats from the Dobrogea Plateau-Romania
For the first time two new habitats from the Dobrogea Plateau – Romania, that can be considered endemic for this region and very rare in Europe, are described in this paper and they are represented by Celtis glabrata woods and Dobrogean wooded steppe. These habitats are also characterized by the occurrence of numerous nationally and/or globally threatened species and plant communities. Thus, we consider that these two habitats should be legally protected as prioritary ones at the national and global levels.
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