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Maintaining and soil fertility improvement are important aims for grapevine growing, taking into account that, in most situations, this species are grown on poor nutritive soils. In these circumstances, efficient systems of fertilization, based on maximum utilization of organically fertilizers, are of present interest. The goal of this study is to explore the correlations between the type of organic fertilizer and grapevine performances expressed in accumulation of biochemical compounds which are involved in plant growth and development. The study was conducted with two grapevine cultivars -Cabernet Sauvignon and Zweigelt -used for high quality red wines production, from vineyards belonging to the National Research and Development Institute for Biotechnology in Horticulture Stefanesti-Arges. Our results revealed the positive effect of soil manuring with organic fertilizer upon the biosyntheses processes in leaves over the vegetative period of main primary metabolites (soluble glucides, chlorophyll pigments and carotenes) and secondary metabolites (proteins, polyphenols, auxins). As a result, woody materials collected from the organic fertilized areas proved to have a better maturation at the beginning of the winter repose period. This was correlated with a better buds viability from yield canes.Zinc and copper are essential elements for growth and development of plants and uptake of these mineral elements by plants is a part of mineral nutrition. Plants have homeostatic mechanisms to maintain the correct concentrations of these metals in their cellular compartments. It is possible to enhance the uptake of these metals by introducing efficient genes for metal uptake from other organisms into plants. Plants with enhanced ability for metal uptake can be developed by introduction of metal transporter genes from other sources. Development of transgenic plants with high efficiency of metal uptake will help in removing toxic levels of these metals from contaminated soils and solutions. With this objective, two metal transporter genes, namely a zinc transporter gene and a copper transporter gene from Neurospora crassa were cloned and individually introduced into plant expression vec-tor pCAMBIA 1301 having hph as a selectable marker and uidA as a reporter gene and transgenic tobacco plants developed by Agrobacterium mediated gene transfer. The transgenic nature of plants was confirmed by PCR and Southern blot hybridization, while expression of transgene was confirmed by reverse transcription PCR. Transgenic plants with zinc transporter gene, when grown in media supplemented with radiolabelled ZnCl 2 , showed enhanced accumulation of zinc in roots (11 times). Uptake of copper was studied in transgenic plants with copper transporter gene and the transgenic plants could take up more copper (2 times) compared to control plants. The present studies have shown that it is possible to develop transgenic plants with improved efficiency for remediation of metals like zinc and copper.Artin M (KM+) is a D-mannose-binding lectin from...

The efficiency of plant sexual reproduction depends on the correct development of the sexual organs: stamen and pistil. Complex molecular mechanisms control cell proliferation and expansion that result in the correct development of these organs. In our laboratory a gene preferentially expressed in Nicotiana tabacum pistil has identified, the 092H06 gene. This gene encodes a small protein of 68 amino acids of unknown function. Previous analyzes suggest that the protein product of the gene 092H06 is responsible for inhibiting the cell expansion process in the reproductive organs (Brito, 2010). To understand the role of this gene in pistil development, experiments of qRT-PCR to determinate the expression levels of the α-expansins, βexpansins, cyclin B1.2 and actin, genes which connected to the cell division and expansion processes, were carried out on transgenic plants silencing and overexpressing the 092H06 gene. Morphological analyzes on stigmas/styles and ovaries of second generation (T2) transgenic plants were performed by optical microscopy. The results show a tendency to increased cellular volume on the silencing transgenic plants, as well as on the overexpressing plants. However, in the silencing plants there was a visible increase of the reproductive structures, what has not been observed on the overexpressing plants. Additionally, flow cytometry experiments were carried out to verify the occurrence of endoreduplication. The results showed that no endoreduplication has occurred on the cells of the transgenic plants. The screening of an yeast two-hybrid assay, using 092H06 as bait, has found 4 interaction partners candidates: 1) biotin/lipolyl attachment domaincontaining protein; 2) unknown protein; 3) trypsin proteinase inhibitor precursor and 4) RING/U-box. To assist the study of the 092H06 function, the recombinant 092H06-HIStag protein has been produced with success, in the soluble form, in E.coli. The results obtained in this work contribute to advance the knowledge of this novel gene expressed on the plant reproductive organs.