Cristina Cruz

I am a lecturer in Plant Biology at the Faculty of Sciences of the University of Lisbon (Faculdade de Ciências da Universidade de Lisboa - FCUL), Portugal, where I have taught and carried out research since 1994.

Within the University I teach in the Department of Plant Biology (Departamento de Biologia Vegetal - DBV), and carry out my research in the Plant-Soil Ecology Group of the Centre for Ecology, Evolution and Environmental Changes (cE3c).

This site describes my work in plant biology, physiology and ecology.

Scientific Interests

I am interested in the physiological mechanisms that determine the suitability of terrestrial plants to their environments, especially in environments rich in ammonium.

My main scientific interest is the physiological ecology of nitrogen (N) acquisition and impacts of increased N availability on terrestrial plants. The distinct effects of NO3- and NH4+ on plant performance and species preference for one of these chemical species of N have been a constant in my research. I am examining the role of plant N fluxes in several key areas: ecological succession, primary productivity, carbon nitrogen interactions, physiology of inorganic nitrogen assimilation and the role of plant micro-organism interactions in nitrogen acquisition. Special attention is given to rhizospheric microbial consortia (free living N fixers, phosphate solubilizers and arbuscular mycorrhizal fungi) in nitrogen acquisition, the mechanisms and fluxes involved are part of the research programme.

My current research is driven by three overarching objectives:

to maintain long-term ecological experiments in order to collect data on the response of Mediterranean ecosystems to changes in resource availability over time and space;
to understand the role of soil ecology on plant productivity and sustainability of eco- and agro-systems;
to engineer the rhizosphere of crop plants in order to obtain plants tolerant of higher stresses, with increased nutrient use efficiencies and nutritional value.

The approach is highly multidisciplinary, ranging from biochemical processes to field ecological analyses. Techniques include enzymatic kinetics, net flux kinetics, ionic and metabolic profiling of tissues, and growth analysis. The biological systems used are carob (Ceratonia siliqua L.), Arabidopsis thaliana and in vitro arbuscular mycorrhizal fungi cultures. New projects are considering the physiology of the endophyte Piriformospora indica and its application as a biofertilizer in order to maintain food security and environmental sustainability.

I recently gave a short talk on my work on Portuguese radio Antena 1's program "90 seconds of science".

Academic qualifications