Research activity focused on the conservation and improvement of forest and aromatic species. It comprises two lines subsidised by MINECO, EU and Valencian Government (PrometeoII):

1. Biotechnology of forest species. Apply somatic embryogenesis (SE) as a tool to increase the resilience of forest species for sustainable forestry. In recent years, we have optimised HE protocols in Pinus pinaster (maritime pine) and Quercus ilex (holm oak), highlighting the selection of Pinus pinaster families with high embryogenic capacity; the creation of a germplasm bank with these lines; the development of genetic transformation protocols in maritime pine and stone pine; and the development, for the first time, of a protocol to establish embryogenic lines of adult holm oak genotypes. The current project (AGL2013-47400-C4-4-R) addresses two strategies for breeding stress-tolerant genotypes. One takes advantage of natural variability and uses the protocols developed to clone and test holm oak genotypes with and without "la seca" symptoms; the second aims to induce epigenetic memory "priming" by applying biotic and abiotic stress treatments during the proliferation-maturation phase. The project also addresses various physiological and molecular aspects of the embryogenic process as a strategy to improve the induction and maturation phases. We collaborate with national forestry HE expert groups from IMIDRA, CSIC and Neiker. The group participates in national and European initiatives using maritime pine as a conifer model for functional genomics studies. In the SustainPine project (Plant-KBBE, PLE2009-0016) we generated transgenic plants with variable levels of expression (overexpression, or silencing with RNAi) of genes involved in growth associated with nitrogen metabolism and which are in the process of evaluation. We also participate in the European project ProCoGen (FP7-KBBE-2011-15) generating a haploid maritime pine cell line that is being used as a source of DNA for the sequencing of its genome.
2. Metabolic engineering of terpenes. It studies the mechanisms that regulate the synthesis and accumulation of terpenes in glandular trichomes of lavender (Lavandula latifolia). All terpenes are derived from the C5 precursor IPP (isopentenyl bisphosphate) and its isomer DMAPP (dimethyl allyl bisphosphate), which in plants can be synthesised via two routes, the cytoplasmic (MVA route) and the chloroplastic (MEP route). To study the contribution of both pathways to final essential oil production, we overexpressed in lavender Arabidopsis genes involved in the first steps of both pathways. We show that the enzyme 1-Deoxy-d-xylulose-5-phosphate (DXP) synthase (DXS), which catalyses the first step of the MEP pathway, plays a crucial role in IPP biosynthesis as its overexpression increases essential oil production in leaves. In contrast, overexpression of the enzyme DXP reductoisomerase (DXR), which catalyses the conversion of DXP to MEP, is not a limiting enzyme in the process. Overexpression of HMG1 (cytoplasmic) also significantly increased essential oil production suggesting an interconnection between the two pathways. To study the contribution of the MVA route to the biosynthesis of lavender oil, studies have been carried out with labelled precursors showing that although the chloroplastic route is the most important, under certain conditions there may be a flow of cytoplasmic IPP into the chloroplast. The essential oil profile has also been modified by overexpressing the linalool and limonene synthase genes without altering the total oil content. The glandular trichome isolation technique is being optimised to complete metabolic studies.

Since 2009 we have been working with the company SAT Even 46 CV to produce healthy mother plants of oleander varieties.

Contributors

• María Amparo Pérez Oliver - Universitat de València.
• Ester Sales Clemente - University of Zaragoza.

Research and experimental development on biotechnology