Metabolic activity of Sphagnum recurvum under different environmental conditions

The fate of transgene is an up-to-date question in plant genetic and breeding research. For a breeder, the ability to transfer foreign gene and its Mendelian inheritance is a very important aspect. In crossing experiments the homogenous T2 transgenic line 124 was crossed with different non-transgenic females. The isolated hybrid embryos from the crosses were tested in medium containing bialaphos. This experiment showed the dominant character of bar gene. All the hybrid embryos germinated onto 5mg/l bialaphos medium expressed resistance, while the control variety (GK Góbé) showed sensitivity to the bialaphos as expected. The fertile T1 generation expressed 3:1 segregation ratio for bar +/bar- plants. The transformed foreign gene (bar) was stable in the wheat genome after two self pollinations and PAT asasays. It is therefore, possible to transform transgene successfully via sexual way into non-transgenic genotypes. Cell level selection of bar gene was possible in anther culture. The regenerated haploids and spontaneous diploids were herbicide resistant. Using in vitro haploid technique (anther culture), it’s possible to produce homogenous bar resistant wheat lines by cell-level selection

Occurrence and properties of the multicopper oxidases laccase and tyrosinase in lichens.

Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.The work presented in this thesis describes the occurrence and properties of two multicopper oxidases derived from lichens. Despite numerous data on laccases and tyrosinases in fungi and flowering plants, this is the first report of the occurrence of these enzymes in lichenized ascomycetes. Extracellular laccase and tyrosinase activity was measured in 50 species of lichens from different taxonomic groupings and contrasting habitats. Out of 27 species tested from suborder Peltigerineae, all displayed laccase and tyrosinase activity that correlated to each other, while activity was absent in species tested from other lichen groups. Identification of the enzymes as laccases and tyrosinases was confirmed by the ability of lichen thalli or leachates to readily metabolize substrates such as 2,2’-azino(bis-3-ethylbenzthiazoline-6-sulfonate) (ABTS), syringaldazine and o-tolidine in case of laccase and L-dihydroxyphenylalanine (L-DOPA), Ltyrosine and epinephrine in case of tyrosinase in the absence of hydrogen peroxide. The activities of both enzymes were highly sensitive to cyanide and azide, and tyrosinase activity was sensitive to hexylresorcinol. Laccase activity had typical pH and temperature optima and an absorption spectrum with a peak at 614 nm. Tyrosinases could be activated by sodium dodecyl sulphate (SDS) and had typical tyrosinase molecular masses of approx. 60 kDa. The diversity of laccase isoforms in 20 lichen species from suborder Peltigerineae was investigated. The molecular masses of the active forms of most laccases varied between 135 and 190 kDa, although some lichens within the family Peltigeraceae had laccases with higher masses, typically varying from 200 to over 350 kDa. Most species contained one oligomeric laccase isoform. Desiccation and wounding stimulated laccase activity, while only wounding stimulated tyrosinase activity. The ability of laccases to decolorize dye is a classic attribute of laccases, and one with biotechnological potential. The ability of eight lichen species to decolourize different types of dyes was therefore tested. Interestingly, results showed that not only species belonging to suborder Peltigerineae but also species from other lichen group effectively decolourised dyes after 48 h suggesting that other oxidases appear to have ability to decolorize. Hopefully, our work could contribute to the better knowledge and application of lichen multicopper oxidases

Ecosystem Services Becoming Political: How Ecological Processes Shape Local Resource-Management Networks

While a landscape usually provides a wide range of benefits, the ecological and spatial entanglement of the processes behind ecosystem services does not allow maximizing benefits from all services at the same time. Different stakeholders relying on different services might therefore prefer different policies and management for the wider area where they operate. Trade-offs, disagreements and mutual interests are rooted in ecological processes but are manifested in the social sphere. Social networks were shown to have a significant impact on the management of ecosystem services. In this paper we show that ecosystem services also influence the structure of management-networks and power-relations among stakeholders, thus ecological factors set the stage for (local-regional) political discourse. We used social network analysis (SNA) to show how ecological processes become agents of social-ecological systems (SES), this method is also useful for finding those players who can adopt a mediator role in the social sphere, having a special position in the web of competing interests. Our research shows how mutual influence between social and ecological elements shapes management strategies in five protected areas in Central and Eastern Europe. The most voluminous and profitable ecosystem services (primarily timber production in our cases) define which stakeholders are the most powerful in management networks—this eminent position allows these players to make decisions unilaterally. Other, smaller players tend to negotiate with a diverse set of counterparts with whom they share and co-manage often multiple services. Power relations that emerge as a consequence of production differences among ecosystem services often do not allow participatory management methods. These situations lead to over-utilization of natural resources with a narrow interpretation of sustainability which decreases resilience for the whole social-ecological system. Our results contribute to the theoretical understanding of political discourses in SES and showcase how SNA can be applied as a tool to facilitate participatory landscape-management. We show how ecological factors co-create the social sphere where decisions are made about sustainable land-use

Co-occurrence of the Multicopper Oxidases Tyrosinase and Laccase in Lichens in Sub-order Peltigerineae

• Background and Aims Following previous findings of high extracellular redox activity in lichens and the presence of laccases in lichen cell walls, the work presented here additionally demonstrates the presence of tyrosinases. Tests were made for the presence of tyrosinases in 40 species of lichens, and from selected species their cellular location and molecular weights were determined. The effects of stress and inhibitors on enzyme activity were also studied