Ex situ Conservation of Three Endemic and/or Endangered Dianthus Species

Within the current context of declining biodiversity, the botanical gardens play an essential role in its conservation. Dianthus callizonus, D. glacialis ssp. gelidus and D. spiculifolius are the species that we seek to preserve in "Alexandru Borza" Botanical Garden of Cluj-Napoca (Romania). Several replicates were collected for each taxon from different populations in order to avoid the genetic uniformity. The material collected from the natural sites, was planted on a rockery, specially designed for this collection in the Botanical Garden. At the time of planting, each individual was sampled for setting up an in vitro collection and further biochemical and molecular analyses. In case of ex situ outdoor conservation of the three Dianthus species, 80.6% of the individuals collected in the field survived during the first year but the percentage decreased drastically after four years. In the case of in situ collected individuals, as well as in the case of in vitro individuals, D. spiculifolius had the best ability to acclimatize in the Botanical Garden, and D. callizonus presented the lowest number of surviving individuals. The ex vitro acclimatization of the plantlets had 80% efficiency at 10ºC, using three different substrates: soil and pearl stone mix 1/1, soil and sand mix 1/1 and pearl stone. All the three species are preserved in vitro, whereas the plantlets are acclimatized outdoors. Ex situ conservation of these species will have a positive impact on the biodiversity conservation.

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Effects of Salinity on the Development of Hydroponically Grown Borage (Borago officinalis L.) Male Gametophyte

In this research, the effect of salinity on the development of anther in hydroponically-grown borage was studied. Plants grown on hydroponic media are rapidly and transiently stressed. The overall objective of this research was to elucidate the microscopic effects of salinity on the formation, development, and structure of anthers. Flowers, at different developmental stages, were removed, fixed in FAA, embedded in paraffin, and cut into 7-10 μm slices using a microtome. Staining was carried out with Hematoxylin-Eosine, and the developmental stages of the control and NaCl-treated plants were compared. In control plants young anther consisted of 4 pollen sacs. Anther wall development followed the typical dicotyledonous pattern and was composed of an epidermal layer, an endothecium layer, and the tapetum. Microspore tetrads were tetrahedral. Salinity caused certain abnormalities during pollen developmental processes, such as the destruction of the anther wall and both the degeneration and production of abnormal pollen grains. A decrease in plant fecundity, which involves aborting pollen, followed by a change in resource from reproductive activities to metabolic reactions is possibly a general response to the deleterious effects of salinity.

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Fertilization Effects on the Chemical Composition and In vitro Organic Matter Digestibility of Semi-natural Meadows as Predicted by NIR Spectrometry

Management of livestock grazing in highly-productive mountain meadows is an important aspect for the economic viability and the environmental impact of a grassland-based farm. The main aim of this study was to build near infrared models to determine the chemical composition and in vitro organic matter digestibility of Romanian meadow forages. The treatments were organic and mineral fertilizer combinations, and forage samples were obtained from three fertilization experiments conducted in the Apuseni Mountains; these samples were analysed using classical and NIR methods. The samples were scanned in the NIR wavelength band. The CRA-W Gembloux ‘local’ calibration models were validated with Romanian meadow forages and then used in order to predict the forage quality of samples. A second objective of the study was to determine the effects of fertilization on forage quality. The results showed a decrease in crude protein content from the NPK treatment (150:75:75), which can be explained by a reduction of Fabaceae plants with this treatment from 17.25% of the populations in the control (semi-natural meadow not fertilized) to 6.25% in the fertilized plots. The decrease in protein content and in vitro organic matter digestibility was related to a reduced Fabaceae presence. Our recommendation is to use mineral fertilization with NPK doses less than 100:50:50 to improve meadow productivity; meanwhile organic fertilization can also be used to complement and maintain biodiversity and forage quality.

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