Plant Nutrients and Food Quality

Research themes

• Theme 1 - Food quality
  Our studies on food quality embrace research activities from farm to fork. We investigate the impacts of management practice and fertilization strategy on the nutritional value of plant-based foods from various plant production systems. This includes organic and conventional agriculture as well as urban farming systems. We conduct studies at field scale, in greenhouses/climate chambers and collaborate with companies specialized in hydroponics and aeroponics.
  
  Food authentication is a major focus point within our food quality activities and it represents a rapidly growing discipline both nationally and internationally. We have developed analytical methods for authenticating the geographical and agricultural origin of a variety of plant products and have documented systematic differences in the isotope signatures of organic versus conventional crops. We currently investigate the underlying biological mechanisms controlling these differences and collaborate with industry partners and authorities on implementation of our methods.
• Theme 2 - Plant nutritional aspects of food quality
  We aim to understand fundamental biochemical and plant nutritional processes and pathways influencing the quality of plant-based food and feed. We study key factors controlling the nutritional status of plants including soil fertility, agricultural management practices and fertilization rate and type.
  
  We seek to develop and utilize novel analytical methods for investigating nutrient availability and utilization in plant metabolism. For example, we use oxygen isotope ratio analysis of sulphate for investigating sulphur availability in soil and utilization in plants. In the coming years we will also investigate microbiome-plant interactions with a strong focus on nutrient availability and utilization.
• Theme 3 - Analytical method development
  Most of our work is based on advanced analytical chemistry – in particular multi-element and stable isotope ratio analysis. Our current multi-element analyses are based on inductively coupled plasma mass spectrometry (ICP-MS) and ICP-optical emission spectroscopy (ICP-OES). In collaboration with research groups at the section, and colleagues from the CHIME analytical center, we have during the past years developed micro-scaled and high-throughput methods covering the majority of elements from the periodic table.
  
  We complement these methods with ion chromatography for anion and cation analysis as well as non-destructive techniques including laser induced breakdown spectroscopy (LIBS), near-infrared spectroscopy and chlorophyll a fluorescence. The latter two techniques are being used for diagnosing nutritional disorders in plants. Regarding stable isotopes, we analyse isotope ratios at the natural abundance level – both in solid, liquid and gaseous samples and have, within the past years, established state-of-the art analytical facilities at the section. In our current work we primarily focus on compoundspecific isotope analysis – e.g. of plant derived oxyanions such as nitrate, sulphate and phosphate.

For students wishing to work within these topics,. M.Sc. and B.Sc. projects are currently available. Please contact Kristian Holst Laursen (holst@plen.ku.dk) for further information.