 |
Hamlyn (Lyn) G. Jones (PhD, FI Hort) Professor of Plant Ecology Plant Research Group Division of Environmental and Applied Biology University of Dundee at SCRI Invergowrie Dundee DD2 5DA Tel: 01382 560003 Fax: 01382 562426 email: h.g.jones@dundee.ac.uk |
As a plant ecophysiologist my research aims to improve our understanding of the characters that enable plants to be adapted to specific environments and to tolerate environmental stress. Both mathematical modelling and experimental approaches, including the use of molecular biological techniques where appropriate, are used to study the genetic and ecophysiological basis underlying differences in the growth and distribution of wild and crop plants. Specific areas of research include the following:
1) Plant water relations and tolerance of environmental stresses : A key theme is understanding the role of plant water relations and its impacts on processes such as photosynthesis, respiration, stomatal closure, osmoregulation, root growth and changes in hydraulic function in plant adaptation to drought. One aim is to identify the genetic basis of drought and salinity tolerance as an aid to crop improvement programmes. Recent work, for example, has identified the expression pattern of salt sensitive genes in barley lines and the mechanisms involved in the control of water flow through plant roots. Much of the research has built on our improved physiological understanding to address critical practical objectives of the improvement of irrigation scheduling techniques for crops in humid environments and the development of improved approaches for applying irrigation. (see projects 3, 5 and 8 below)
2) Thermal imaging and remote sensing of vegetation : A major theme in our recent work has been the development of remote sensing approaches, especially based on thermal imaging, to study stomatal behaviour of crop plants and for the diagnosis of environmental constraints. Remote sensing from satellites, aircraft and land-based monitors provides a range of powerful tools for assessment of vegetation and its performance and for the diagnosis of environmental constraints. Efficient use of techniques such as infra-red thermometry, fluorescence or multi-spectral and multi-angular reflectance requires an understanding of the canopy architecture and heterogeneity. Our work aims to contribute to the measurement and modelling of these soil-vegetation-atmosphere transfer (SVAT) processes, and to the scaling-up of leaf- and plant-scale observations to the canopy level. (see projects 1, 2, 3 and 4 below)
3) Weather-crop yield relationships and the impacts of climate change : An area of interest is the study of potential impacts of climate change (e.g. drought, CO2, temperature and UV-B radiation) on plants and ecosystems. Statistical approaches for identifying environmental factors limiting crop yield and quality have been developed in collaboration with SCRI and Scottish raspberry growers. The potential impact of climate change and especially variation in the amount of winter chill on soft-fruit production and the future of the fruit industry is of special interest here. Methods for improving the reliability of cropping and to extend the season are also being developed. Other work on UV-B has demonstrated the links between responses to UV-B and other stresses such as drought. The role of temperature in determining the distribution of plant species is a particular interest, with particular emphasis on understanding the adaptations to low temperature environments (including the arctic) and the potential impact of climate change in these marginal environments. Consequences of either low- or high-temperature extremes for respiratory and photosynthetic performance are quantified using gas-exchange and chlorophyll fluorescence techniques, while we have developed a new approach to study the regulation of the engagement of the alternative oxidase electron transport pathway in the field using isotopic discrimination against 18O. (See projects 6 and 7 below)
Dr Ilkka Leinonen : post-doctoral researcher who works on the EU STRESSIMAGING Research Training Network. He is particularly concerned with devising automated approaches for the handling of thermal and digital images and their merging and automated analysis in studies of plant stress. (e-mail: ileion@scri.sari.ac.uk)
Dr Ryan Ramsey : post-doctoral researcher who works on Defra-funded project on the development of partial root-zone drying techniques for improvement of irrigation techniques for the potato, raspberry and runner bean crops. (e-mail: rramse@scri.ac.uk)
Dr Oleg Stasyk : visiting scientist from Kiev works on high temperature tolerance of photosynthetic systems in cereals.
Dr Peter Schofield : post doctoral researcher who works on a Defra Horticulture Link project to develop thermal imaging approaches for the automated control of irrigation for ornamental nursery stock. The approaches involve the development and testing of engineering solutions to automation of irrigation control. (e-mail: p.schofield@dundee.ac.uk)
Dr Stefania Pisanu: post-doctoral researcher on STRESSIMAGING project investigating the use of multiangular and thermal imagery for stress diagnosis in field crops, using NERC ARSF airborne data collected over field crops in Italy (in collaboration with Professor R Casa, Viterbo and Dr Alan Blackburn, Lancaster)
Dr Tsonko Tsonev , Dr Violetta Velikova and Dr Maya Lambreva: three scientists from the Bulgarian Academy of Sciences, Sofia , working on a joint NATO collaborative linkage grant on NATO (CLG 982412 on “Plants from ultramafic sites as tools for remediation”) .
Lynda Spencer : technician.
Recent group members
Dr Nicole Archer : estimation of water use by heterogeneous Mediterranean ecosystems (WATERUSE project - funded under the Energy, Environment and Sustainable Development Programme of the EU; This work also involved the use of aerial and satellite remote sensing for the estimation of water use by Mediterranean vegetation. (e-mail: nicole.archer@agrar.uni-giessen.de))
Dr Rob Sunley : the role of winter chill on productivity of soft fruit and the potential impact of climate change (funded by DEFRA in collaboration with Dr Rex Brennan at the Scottish Crop Research Institute and Dr Chris Atkinson at HRI, East Malling). (e-mail: robert.sunley@psd.defra.gsi.gov.uk)
Dr Olga Grant: optimisation of partial rootzone drying and the use of thermal imagery for plant stress sensing (e-mail: olga.grant@emr.ac.uk).
Dr Marina Chechulina : Royal Society/NATO postdoctoral fellow from Tashkent , Uzbekistan , working on salt tolerance in barley (in collaboration with Dr Brian Forster and Dr Peter Hedley of the Scottish Crop Research Institute) (e-mail: Marina.cheV@mail.ru)
Dr Lydia Vysotskaya : Royal Society postdoctoral fellow from Ufa , Russia , working on water relations and control of hydraulic conductivity in cereals. (e-mail: vysotskaya@anrb.ru)
 |
 |
|
Ilkka Leinonen , Ryan Ramsey , Lydia Vysotskaya, Lynda Spencer, Lyn Jones |
Lyn Jones, Violetta Velikova, Katya Georgieva, Tsonko Tsonev | |
 |
 |
 |
| Ryan Ramsey | Stefania Pisanu and Ryan Ramsey measuring water potential in PRD raspberries | Sikja Lipitsainen and Ilkka Leinonen during fieldwork in Portugal |
Some Examples of Current Projects
1) Remote sensing of stress: A number of approaches are being evaluated for the diagnosis and monitoring of plant stress
One involves the use of the Dundee Variable Interference Imaging Spectrometer (VIFIS), in collaboration with the Dundee Centre for Remote Sensing and Environmental Monitoring. We have used this system, illustrated, to investigate the opportunities to use both spectral and angular reflectance data to monitor water and nitrogen stress in potato canopies and evaluated a range of simpler sensors for this purpose. Recent work has involved the development of image classification techniques for extraction of canopy parameters from standard or modified digital camera images. (contact: rcasa@unitus.it)
 |
 |
VIFIS camera being used to obtain multiangular, hyperspectral images of a potato canopy. These images can then be classified into sunlit and shaded fractions of leaf and soil to allow estimation of canopy leaf area index and leaf angle distribution. The two lower images illustrate the success of the image classification algorithm used. (photo R Casa) |
2) Thermal imaging of plant leaves and canopies
An alternative approach to the remote sensing of plant stress is the use of thermal remote sensing/thermal imaging. Canopy temperature increases as stomata close when crops require water. Over the past few years we have been developing the use of thermal imaging for detecting plant stress responses and scheduling irrigation (e.g. IRRISPLIT Project, DEFRA HortLink, GWRDC). We have developed the theory of thermal imaging to the extent that we have proposed new more robust methods for estimating stomatal conductance from thermal imagery in the field.
 |
False colour thermal image (right) of grape-vine leaves, showing the temperature difference between non-transpiring (42 oC light blue-green) and wet (25 oC blue-black) areas of the leaves. |
3) Remote estimation of Evaporation from vegetation
Thermal imaging and infrared thermometry are being applied across a range of projects for both practical irrigation control and for crop phenotyping. For example, in collaboration with Dr Brian Loveys, CSIRO, Adelaide, we are investigating the use of thermal sensing for the scheduling of irrigation in grape-vines on a large scale in commercial vineyards. Methods for automation of image analysis when handling large numbers of thermal images (see illustration), for example in robotic imaging systems, have been developed in an EU-Research Training Network (STRESSIMAGING http://www.dundee.ac.uk/lifesciences/stressimaging/). In a HORTLINK project we are applying these techniques to the development of novel approaches to automate irrigation in Hardy Nursery Stock production nurseries to optimise water use, to reduce labour inputs and to improve plant quality. This project is in collaboration with the University of Lancaster, East Malling Research, PERA Ltd, Denton Automation, and a number of other partners. In other work in collaboration with Dr Adam Price, University of Aberdeen and Dr Serraj Rachid of the International Rice Research Institute, Philippines, we are testing the use of thermal imaging for crop phenotyping for drought tolerance in the field (see illustration).
 |
An illustration of the automated image analysis procedure for determining the temperatures of plant canopies for application in automated irrigation scheduling. The process involves overlaying the thermal and Red/NIR images, identifying the areas of leaf in the Red/NIR image and then extracting the corresponding temperatures. |
 |
Illustration of a rice drought tolerance screening trial at IRRI, with a corresponsding thermal image showing genotypic variation in leaf temperature, and hence stomatal conductance, in response to drought (collaboration with Dr Serraj Rachid). The inset histogram shows the distribution of leaf temperatures for droughted and irrigated plots within this trial. |
4) Remote estimation of Evaporation from vegetation
Thermal remote sensing both at canopy level and using airborne and satellite sensors is being developed for estimation of evaporation rates from large areas of heterogeneous canopies. This work was initially conducted under the (EU WATERUSE Project - http://www.isa.utl.pt/wateruse/) and has included the acquistion of aerial hyperspectral imagery under the EU- HYSENS programme - http://www.op.dlr.de/dais/hysens/hysens.htm). Recent studies have included collaborations with Prof R Casa, Viterbo and Dr Alan Blackburn at Lancaster University using NERC ARSF imagery obtained over Italy, with the aim of developing robust algorithms for the extraction of canopy characteristics from multiangular and multispectral imagery.
 |
| View of cork oak stand near Evora, Portugal, together with airborne images, showing (top: red/near IR reflectance, middle: classified image, bottom: thermal image). The classified image can then be used to extract temperatures of the different classes of vegetation for estimation of their transpiration rates |
5) Use of partial rootzone drying (PRD) to improve irrigation efficiency
The development of PRD irrigation techniques is based on our earlier work on root-shoot signalling (see e.g. Gowing et al. 1993); we are now developing this on a Defra-funded project jointly with the University of Lancaster and East Malling Research, aiming to identify the conditions under which PRD is likely to be most successful and the ways in which the efficiency of irrigation can be improved for different crops. Current activity concentrates on the evaluation of the technique for raspberry, potato and runner bean.
 |
 |
A PRD experiment on potato, with irrigation being applied one side of the row in the left-hand image and irrigation being applied both sides in the right-hand image. |
|
6) Respiration in low temperature environments
Under a NERC small grant in collaboration with SURRC at East Kilbride we have developed methods for discriminating between the cytochrome and alternative oxidase pathways of respiration by means of the differential discrimination of these two pathways for the different isotopes of oxygen and applying these to a study of adaptation of plants to arctic environments. The incubation system we have developed is suitable for use off-line from the Mass-Spectrometer and is now being extended to use in field. Recent work has investigated the respiratory behaviour of a wide range of plant species from contrasting habitats from the arctic to the tropics, and their different acclimatory responses to temperature.
 |
Equipment used for the incubation of tissue samples for the collection of oxygen samples for analysis of O 16/O 18 ratio on a mass spectrometer (Nagel et al. 2001) |
7) Climatic effects on soft fruit production
In a Defra-funded collaboration with Rex Brennan of SCRI and Chris Atkinson at East Malling Research we have been investigating the potential effect of climate change on soft fruit production within the UK. There has been concern among growers that increasing winter temperatures mean that the cooling requirement for effective flowering is becoming less frequently satisfied with potential serious consequences for yield. The results of these analyses suggest that the detrimental impact of increasing temperatures are likely to be much the greatest in the South of England with much less impact in Scotland .
8) Plants from ultramafic sites as tools for bioremediation
In a NATO collaborative linkage grant with Dr Tsonev and colleagues from the Bulgarian Academy of Science we are investigating the physiological basis of adaptation of plants to ultramafic soils using closely related pairs of plants from non-ultramafic and ultramafic (Serpentine) sites such as Meikle Kilrannoch in Scotland, Keen of Hamar in Shetland, and the Rhodopi mountains in Bulgaria. A particular interest in this study is the role of reactive oxygen species (ROS) in the physiological responses to heavy metal toxicity of the contrasting genotypes.
New Project/Positions available
Enquiries are welcomed at any time by potential visiting scientists and for Fellowships and Studentships. Other opportunities are advertised as they appear on the School of Life Sciences website and on jobs.ac.uk as they arise.
The University of Dundee is committed to equal opportunities and welcomes applications from all sections of the community.
Further details on research in the College of Life Sciences at the University of Dundee can be found at : http://www.dundee.ac.uk/biocentre/SLSBOverview.htm.
Further information on the Scottish Crop Research Institute can be found at: http://www.scri.sari.ac.uk.
