Plant ecophysiology and metal abiotic stress

Dr Denise R. Fernando

'Manganese Heavy Metal Toxicity in Plants: New Perspective on a Neglected Problem'

I investigate plant ecophysiological processes associated with stress and extreme tolerance; primarily through field studies.  My research includes investigating the impacts of environmental change, plant mineral nutritional dynamics, foliar metal accumulation and the heavy metal manganese (Mn), which is soil abundant and essential to plants.  I recently completed an ARC DECRA-funded project titled, ‘Manganese (Mn) Heavy Metal Toxicity in Plants: New Perspective on a Neglected Problem’, which focused on plant ecophysiological processes associated with the heavy metal Mn. Soils in eastern Australia are Mn-enriched, therefore while agricultural plants are affected by Mn toxicity, indigenous plants are well adapted, including some that even exhibit the rare trait of Mn hyperaccumulation. Foliage Mn accumulation under controlled conditions and in the field have been examined so as to better understand wide-ranging plant physiological responses elicited by Mn oversupply.  Given that certain climatic conditions give rise to Mn stress in plants, it is essential to ascertain the mitigating effects of climatic factors on plant nutritional and physiological imbalance. Analytical electron microscopy is utilised as an investigative tool to resolve cellular nutrient accumulation.  I have collaborated with Professor Jonathan Lynch of Pennsylvania State University, to study acid-soil driven Mn stress in maple trees.  We continue to collaborate on researching the mineral nutritional health of native Eucalyptus trees on Australia’s Murray Darling Basin. My research into highly Mn-tolerant native Australian plant ecosystems has established a long-standing collaborative partnership with the Queensland Herbarium, Brisbane.  I also have collaborative associations with scientists at Charles Sturt University, examining Mn crop toxicity in field canola and in experimental wheat and soybean.

In 2017 I completed fieldwork in Sri Lanka, working on a project funded by the National Geographic Society, as part of ongoing research in to the unusual floras and geochemistry of its serpentine floras.  This work is being undertaken in collaboration with the National Institute of Fundamental Studies, Sri Lanka, and the California Polytechnic State University, USA.

I am currently conducting pilot studies in the Murray Darling Basin, investigating the nutritional and physiological health of its native Eucalyptus tree species.  This research is in collaboration with Dr Jane Roberts, scientists from the MDFRC, CSIRO, University of Canberra, Griffith University and Pennsylvania State University.