REPORT | PROGRAMME | ABSTRACTS | POSTERS

1. Application of a novel 3D imaging system for non-destructive growth analysis of the C4 plant Flaveria bidentis

Jasper J. L. Pengelly¹, Xavier R. R. Sirault², Robert T. Furbank² and Susanne von Caemmerer^{1 1}ANU and High Resolution Plant Phenomics Centre ²CSIRO and High Resolution Plant Phenomics Centre The growth of a plant can be calculated experimentally by conducting a series of destructive harvests of a population of the plant over a given growth period. Measurement of the average increase in weight, leaf area or volume of the groups of plants harvested at each time-point can be used to determine the relative growth rate (RGR). This technique requires a large initial population of plants, and is based on the assumption that data derived from each harvest point is an accurate estimate of the population at that time. This limits its effectiveness in the analysis of segregating transgenic plant populations in which mutation-linked growth changes may be missed if plants at each harvest do not express a mutation equally. We adapted a novel real-time imaging technique to measure plant growth in a non-destructive manner. Successive multi-angle photographic images of individual plants over a time period are used to generate a RGR based on mathematically derived plant volumes at each imaging time. A pilot study using the C₄ dicotyledon Flaveria bidentis showed that plant volumes obtained from imaging correlated well with dry weight measurements in determining plant growth. Central to the C₄ photosynthetic pathway in F. bidentisis the cytosolic enzyme phosphoenolpyruvate carboxylase (PEPC), which is activated through a light-dependant phosphorylation by a specific protein kinase (PEPC-PK). Here we present data on the effects of low (150 µmol quanta m^-2 s^-1) and high (500 µmol quanta m^-2 s^-1) light on the growth and photosynthetic efficiency of individual F. bidentis wild type (WT) and anti-sense PEPC-PK mutants over a 6-week time period. Parallel destructive harvests were carried out on WT plants to validate growth data obtained from imaging.

2. Coordinated Regulation of Secondary Cell Wall Biosynthesis by Homeodomain Transcription Factors

Nataliya Kovalchuk University of Adelaide, Australian Centre for Plant Functional Genomic The homeodomain transcription factor genes, TaHDZipII-1 and TaHDZipI-2, were isolated from developing wheat grain using a cis-element as bait in a yeast one-hybrid screen. Ectopic over-expression of TaHDZipII-1 and TaHDZipI-2 in transgenic barley plants leads to a series of plants showing many opposite phenotypes, including: early versus late flowering time, dark versus light plant and grain color, short versus long spikes, and large versus small grain. Both transgenics have reduced growth rates compared to control plants. Scanning electron microscopy shows that the epidermal cells in the stem of TaHDZipII-1 transgenic plants are about 2-3 fold longer than in control barley plants. Microscopic examination of stem sections of the same plants plants revealed collapse of cell walls in vascular bundle sheath cells, similar to irregular xylem phenotype (irx) previously described for mutants in genes encoding enzymes involved in the secondary cell wall and particularly lignin biosynthesis. Analysis of expression levels of several genes encoding transcription factors and enzymes specific to secondary cell wall biosynthesis in control and transgenic plants revealed strong and coordinated down-regulation in TaHDZipII-1 transgenics and up-regulation in TaHDZipI-2 transgenics. Lower levels of lignin and cellulose were found in TaHDZipII-1 transgenics, while TaHDZipI-2 plants showed redistribution of lignin in leaf tissues relative to controls. These data suggest that TaHDZipII-1 and TaHDZipI-2 act as negative and positive regulators of the same group of genes associated with secondary wall biosynthesis. These transcription factors regulate plant growth and development by modulation of cell expansion through either repression or activation of the secondary cell wall biosynthesis.

3. Responses of spectral reflectance indices and whole-plant shape to reversible and irreversible water stresses in cucumber, tomato and melon plants

M. Takasago, R. Endo^*, M. Endo and K. Omasa Graduate School of Agricultural and Life Sciences, The University of Tokyo ^*Presenter address: Graduate School of Life and Environmental Sciences, Osaka Prefecture University Plants can vary spectral reflectance of their leaves and whole-plant shape when exposed to water stress. By utilizing these features, various spectral reflectance indices have been developed as an indicator of water status. However, the relationships of the reflectance indices and whole-plant shape with accompanying the progress of water stress are not clear. In this study, firstly, reflectance indices like WBI, NDWI, NDII and MSI were calculated from the spectral reflectance derived from both leaves and whole-plants in cucumber, tomato and melon plants, respectively. Subsequently, relationships between these indices and water potential were compared in the range of both reversible and irreversible water stresses. Furthermore, the series of time-course images from over the whole-plants were captured in each plant after stopping irrigation. From these images, the relationships of the reflectance indices and whole-plant shape under the progress of water stress have been shown.

4. Quantitative analysis of responses of stomatal conductance, FPSII and whole-plant shape to early water stress in cucumber plants

R. Endo^*, M. Endo and K. Omasa Graduate School of Agricultural and Life Sciences, The University of Tokyo ^*Presenter address: Graduate School of Life and Environmental Sciences, Osaka Prefecture University Relationships between responses of stomatal conductance, FPSII and whole-plant shape to early water stress in cucumber plants were quantitatively investigated for the non-destructive detection. Both stomatal conductance and FPSII have shown a good relationship with water potential in the range that plants can recover from water stress (from 0 MPa to -1.5 MPa). Especially, stomatal conductance responded earlier water stress sensitively compared to FPSII. Water potential is expressed as the sum of osmotic potential and pressure potential, which is a driving force to transfer the water from roots to leaves. The change of stomatal conductance after stopping irrigation was very similar to that of pressure potential, indicating that the change of whole-plant shape could also reflect early water stress sensitively. Therefore, time course images from over the plant just after stopping irrigation have been captured by a CCD camera. Subsequently, the captured images were divided into the plant area and the soil area by image processing. Consequently, the coverage of the whole-plant to ground area has a good correlation with water potential. This result indicates the effectiveness of imaging approach as an easy and fast detector of water stress.

5. Phenomics-based screening for salinity tolerance: A case study for the evaluation of the impact of salinity on growth of barley and faba bean

Tavakkoli, E.¹, Rengasamy, P.² and McDonald, G.K.^{1 1} School of Agriculture, Food and Wine, ² School of Earth and Environmental Sciences, The University of Adelaide, Private Mail Bag 1, Glen Osmond, SA 5064, Australia Salinity reduces crop productivity in many agricultural areas, especially in arid and semi-arid regions. Growth is reduced by osmotic effects and ion-specific mechanisms. While Munns et al (1995) proposed a two-phase model of salt injury, where growth is initially reduced by osmotic stress and then by Na+ toxicity, it is currently difficult to assess the relative importance of the two mechanisms to yield reduction because they overlap. The objectives of this experiment were to evaluate the mechanisms of salt tolerance in barley and faba bean and to quantify the injury of seedlings suffered under NaCl stress. A factorial soil-based experiment examined the effect of different concentrations of NaCl (0, 25, 50, 75 and 100 mM) and concentrated macro-nutrient solution on the growth of two varieties of barley (Clipper and Sahara) and two varieties of faba bean (Cairo and Fiesta). These varieties were selected from previous screening experiments because of their differences in salt tolerance. The experiments were a completely randomised design with 6 or 5 replicates. Non-destructive and near-real-time measurements of plant growth were made during the experiment using a LemnaTec Scanalyzer®. Destructive harvests were used to measure Na+, K+ and Cl-concentration, organic compounds and leaf osmotic potentials. Gas exchange studies were made at different times using a LI-COR 6400 portable gas exchange system. Physiological analyses of these traits in relation to the different mechanisms of salt tolerance and their suitability as selection parameter will be discussed. Key words: Na+, Cl-, osmotic stress, salt tolerance, barley, faba bean

6. LINKAGE BETWEEN Na+ EXCLUSION AND FLOWERING TIME GENES IN BARLEY CHROMOSOME 7H: GENOTYPING AND PHENOTYPING

Shavrukov Y¹, Baho M², Langridge P¹, Tester M¹ and Collins N^{1 1} Australian Centre for Plant Functional Genomics, University of Adelaide, Urrbrae, SA 5064, Australia ² University of Al-Mustansiriya, Baghdad, Iraq A single QTL for Na+ exclusion was initially identified in an Advanced Backcross-QTL (AB-QTL) population of 325 DH lines, in which chromosome segments of the wild barley (Hordeum spontaneum) accession CPI-71284 were introgressed in to the background of the South Australian barley variety Barque. The QTL had high significance (LRS = 45.6), accounted for 51% of the total phenotypic variation, and located to the short arm of chromosome 7H, 57.5-75.6 cM from the distal end. The locus was delimited further using eleven CAPS markers developed using gene co-linearity with rice chromosome 6, including one marker made from the barley Flowering Time (FT) gene, which is a candidate for the Vrn-H3 vernalization response gene. The markers were scored in 200 Barque x CPI-71284 F2 plants, and the Na+ exclusion locus genotype was determined in selected recombinants for the region by progeny testing. Notably, the Na+ exclusion trait mapped 9 cM proximal of FT, indicating that it was not a result of any developmental effects controlled by FT and it is unlikely that the FT gene plays a role in Na+ exclusion. The value of the Na+ exclusion locus will be evaluated by yield trials of selected lines grown in saline field conditions.

7. Assessing the Comparative Response of Wheat and Barley Genotypes to Salinity Stress using Destructive and Non-destructive Techniques

Berger, B.¹, Tavakkoli, E.², McDonald, G.K.², and Tester M.^{1,2 1} The Australian Centre for Plant Functional Genomics, ²School of Agriculture, Food and Wine, University of Adelaide, Private Mail Bag 1, Glen Osmond, SA 5064, Australia Salinity reduces crop productivity in many agricultural areas, especially in arid and semi-arid regions. Growth is reduced by osmotic effects and ion-specific mechanisms. While Munns et al (1995) proposed a two-phase model of salt injury, where growth is initially reduced by osmotic stress and then by Na+ toxicity, it is currently difficult to assess the relative importance of the two mechanisms to yield reduction because they overlap. The objectives of this experiment were to evaluate the mechanisms of salt tolerance in wheat and barley and to quantify the injury of seedlings suffered under NaCl stress. A factorial experiment examined the effect of NaCl (100 mM),) on the growth of two varieties of bread wheat (Krichauff, Berkut), two varieties of durum wheat (Line 149 and cv Tamaroi) and four varieties of barley (Clipper, Sahara, Mundah and Keel). These varieties were selected because of their differences in salt tolerance. The experiment was a completely randomised design with 8 replicates. Non-destructive and near-real-time measurements of plant growth were made during the experiment using a LemnaTec Scanalyzer^®. Destructive harvests at selected time points were used to assess the growth of plants and to measure changes in Na+, K+ and Cl- concentrations and leaf osmotic potentials. Gas exchange studies were made at different times using a LI-COR 6400 portable gas exchange system. Physiological analyses of these traits in relation to the different mechanisms of salt tolerance and their suitability as selection parameter will be discussed. Key words: Na+, Cl-, osmotic stress, salt tolerance, wheat, barley

8. A timing mechanism for stem cell maintenance and differentiation in Arabidopsis flower development

Bo Sun^1,2, Yifeng Xu¹, Kian-Hong Ng¹, Toshiro Ito^{1,2,3 1}Temasek Life Sciences Laboratory, ²National University of Singapore, ³PRESTO, Japan Science and Technology Agency Strict control of stem cell activity ensures that plants of the same species have similarly sized flowers with a fixed number of floral organs. In flower development, the population of stem cells in the floral meristem is terminated after the production of a fixed number of floral organ primordia. Precise repression of the Arabidopsis thaliana homeobox gene WUSCHEL (WUS) by the floral homeotic protein AGAMOUS (AG) plays a major part in this process. Here we show that KNUCKLES (KNU) mediates the repression of WUS in floral meristem determinacy control. AG directly induces the transcription of KNU, which encodes a C2H2-type zinc finger protein with a conserved transcriptional repression motif. In turn, KNU represses the WUS transcription to abolish stem cell activity. We also show the timing of KNU induction is key in balancing proliferation and differentiation in flower development. Delayed KNU expression results in an indeterminate meristem, whereas ectopic KNU expression prematurely terminates the floral meristem. Furthermore, KNU induction by AG is preceded by changes in repressive histone modification at the KNU locus, which occurs in an AG-dependent manner. These data indicate a mechanistic link between developmental timing control and epigenetic control in plant stem cell proliferation. AGI codes: At5g14010, At4g18960, At2g17950

9. Whole cell wall solubilization/2D NMR spectroscopy as a secondary screening method for sampling heterogeneity in compression wood cell walls

B. Nanayakkara¹, H. Kim² and J. Ralph^{2 1}Scion, Rotorua 3010, New Zealand ²Department of Biochemistry and the Great Lake Bioenergy Research Center, University of Wisconsin, Madison, Wisconsin 53706. Softwood species such as pine react to gravitropic stimuli by producing compression wood (CW). CW possesses altered physical, anatomical and chemical properties and functions to re-orient a leaning stem or branch. The uneven distribution of CW in timber causes dimensional instability and warping of wood upon drying resulting in poor product performance. CW is highly lignified, and contains less cellulose and galactoglucomannan than normal wood. CW lignin has more p-hydroxyphenyl units, fewer ß-O-4 linkages and more carbon-carbon linkages between lignin monomer units. Whole cell wall dissolution followed by 2D and 3D NMR spectroscopy of acetylated cell walls for “fingerprinting” and detailed characterization of the cell walls is an emerging technique. Ball-milled wood (cell walls) can be fully dissolved in a mixed solvent of dimethylsulfoxide and N-methylimidazole, and, once acetylated, these cell walls readily dissolve in common NMR solvents allowing the application of high resolution solution state NMR methods. In this poster the application of the whole cell wall solubilization/2D NMR screening technique to Pinus radiata CW is described. A comparison is given between CW and opposite wood (OW) which is the wood type formed on the diametrically opposite side to CW. Significant differences were seen in proportions of p-hydroxyphenyl and guaiacyl (derived from p-coumaryl and coniferyl alcohols) in the aromatic region of 2D ¹³C-¹H correlation (HSQC) spectra. Despite this difference the distribution of the various inter-unit linkages (ß-O-4, ß-ß, ß-5 etc) in side-chains of lignin were similar in CW and OW cell walls.

10. Terahertz imaging of leaves

Andrew Hellicar, Li Li CSIRO ICT Centre The terahertz region of the electromagnetic spectrum lies above the microwave and below the infrared regions. Whereas infrared is unable to penetrate far through the surface of plant materials, and microwaves are unable to provide millimetre-scale resolution, terahertz waves are capable of both. Terahertz frequencies also exhibit high sensitivity to water content (water is highly absorbing) and are non-ionising and hence safe for humans. These characteristics make terahertz ideal for the non-destructive non-invasive imaging of the water content of leaves. A flexible imaging system has been constructed within the CSIRO ICT Centre for exploring applications of terahertz imaging. An experiment was conducted examining the transmission images through a plant leaf as the plant was water starved over the course of 5 days. Results from this will be presented and the variation of image quality with frequency and cost of system trade-offs will be discussed.

11. An IR-Based Index to Screen Plant Transpiration and Environmental Stress

Guo Yu QIU^1,2 Kenji OMASA^{3 1} State key laborato 5 ry of earth surface processes and resource ecology (Beijing Normal University), Beijing 100875, China ² Key laboratory for environmental and urban sciences,Shenzhen Graduate School, Peking University, Shenzhen 518055, China ³Graduate school of agricultural and life sciences, the University of Tokyo, Tokyo 113-8657, 10 Japan Plant transpiration rate can sensitively response to water and other environmental stresses (heat, pollution, and etc.). In this study, firstly, by introducing a reference leaf (a leaf without transpiration), a IR-based index of plant transpiration transfer coefficient (hat) is proposed for estimation of plant environmental stress and transpiration rate, which can be expressed as hat = (Tc-Ta)/(Tp-Ta), where Tc and Tp is the surface temperature of leaf and reference leaf, respectively, Ta is the air temperature. The value of hat is in the range of hat = 1, larger value indicating higher stress level. Then, the proposed hat is applied to detect the environmental stress caused by water shortage and high temperature for melon, tomato, and lettuce plants under various conditions. Results show that water and heat stresses can be sensitively screened by this IR-based index. Finally, hat is compared with the conventional crop water stress index and results again show that there is a reasonable agreement between them. The main advantage of the IR-based hat is its sensitivity to environmental stress and its simplicity for applications.

12. Detecting seasonal change of broad-leaved woody canopy leaf-area-density profile using 3D portable lidar imaging

Fumiki Hosoi , Yohei Nakai and Kenji Omasa^* Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan ^*Corresponding author: Tel.: +81-3-5841-5340; Fax: +81-3-5841-8175 E-mail: aomasa@mail.ecc.u-tokyo.ac.jp Seasonal change of vertical leaf area density (LAD) profiles of woody canopy broad-leaved trees was estimated using 3D portable lidar imaging. First, 3D point cloud data for a Japanese zelkova canopy (Zelkova serrata [Thunberg] Makino) were collected using the portable lidar at four seasons, spring, summer, autumn and winter. In the data collection, the tree canopy was fully and evenly scanned by the lidar from several positions 10m above the ground. Second, collected data were co-registered into a 3-D point cloud image with common coordinates in each season. Winter season data included no leaves in the image, thus the data was utilized for eliminating non-photosynthetic tissues from three season’s data. Third, vertical LAD profiles in each season were computed from the registered lidar data based on the voxel-based canopy profiling (VCP) method, in which contact frequency of laser beams to leaves was computed using the voxel attributes for obtaining LAD values. The accuracy of LAD computation was validated by comparing the estimate with the direct leaf sampling data. The resultant profiles showed the tendency that LAD values increased as the season changed from spring to summer and decreased from summer to autumn. Moreover, seasonal change of vertical LAD distribution was investigated.

13. 3D monitoring of spatio-temporal effects of herbicide on a whole plant using combined range and chlorophyll a fluorescence imaging

Atsumi Konishi^*, Akira Eguchi, Fumiki Hosoi, and Kenji Omasa Graduate School of Agricultural and Life Sciences, The University of Tokyo, aomasa@mail.ecc.u-tokyo.ac.jp ^*present address: YANMAR Marine Farm Spatio-temporal effects of herbicide including 3-(3,4 dichlorophenyl)-1,1-dimethylurea (DCMU) on a whole melon (Cucumis melo L.) plant were three-dimensionally monitored using combined range and chlorophyll a fluorescence imaging. The herbicide was treated to soils in the pot and the changes in chlorophyll a fluorescence images of the plant were captured over time. The time series of chlorophyll fluorescence images were combined with 3D range image of the whole plant taken by a high-resolution portable scanning lidar (light detection and ranging). From the produced 3D chlorophyll fluorescence images, it was observed that increase of chlorophyll a fluorescence appeared along veins of leaves and gradually expanded to mesophylls. In addition, it was found by detailed analysis of the images that invisible herbicide injury on the mature leaves occurred earlier and more severely than on the young and old leaves. The findings showed that 3D monitoring using combined range and chlorophyll a fluorescence imaging can be utilized for detecting and understanding spatio-temporal changes of herbicide effects on a whole plant. These changes also indicated difference in uptake of herbicide in the plant from soil.

14. Chlorophyll fluorescence imaging for evaluation of photosynthetic function of tomato plants in a greenhouse

Kotaro Takayama¹, Hiroshige Nishina¹, Kazuhiro Mizutani¹, Seiichi Arima¹, Kenji Hatou¹, Yuzuru Miyoshi¹ and Kenji Omasa^{2 1}Faculty of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan, takayama@agr.ehime-u.ac.jp ²Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo 113-8657, Japan Keywords: agriculture, diagnosis, growth, monitoring, photosynthesis Chlorophyll fluorescence imaging allows us to evaluate photosynthetic function of plants without touching. By applying a measuring light on a dark-adapted leaf, a dynamic change in chlorophyll fluorescence intensity is induced and the time course is called “induction curve”. The shape of the curve is characterized with O-I-D-P-S-M-T phases and varies depending on the status of the photosynthetic function. In this study, we developed a chlorophyll fluorescence imaging system to measure induction curves of tomato plants grown in a greenhouse. A 60cm x 60cm LEDs panel provided the measuring light at a PPFD of 100 µmol m^-2s^-1 to illuminate the leaves around the shoot apex of a tomato plant. And, the induced chlorophyll fluorescence was measured by an infrared CCD camera fixed in the middle of the LEDs panel. Chlorophyll fluorescence imaging was performed at night. We measured induction curves of 60 tomato plants and then created the maps of chlorophyll fluorescence parameters in the greenhouse. The map of P/ave(S:M), the ratio of the peak (P phase) height to the subsequent flat part (S-M phase) height of an induction curve, showed a significant positive gradient from west to east across the greenhouse.

15. Non-invasive analyses of plant morphology and function: towards the creation of a phenotypic database

Furbank RT^1,2, Sirault XRR^1,2, Estavillo G³, Fallahi H¹, Pogson B^{3 1}CSIRO Plant Industry, Black Mountain, Cnr Clunies Ross St and Barry Drive, Canberra, ACT 2601, Australia ²Australian Plant Phenomics Facility, the High Resolution Plant Phenomics Facility, Cnr Clunies Ross St and Barry drive, Canberra, ACT 2601, Australia ³The ARC Centre of Excellence in Plant Energy Biology, The Australian National University, Canberra, Australia Qualitative analysis of plant phenotypes can be improved by the use of non-invasive techniques for data acquisition. Plant imaging and image analysis allows for periodic, non destructive sampling. This approach requires less starting material than classical destructive methods, and growth of an individual plant can be recorded over time. Another advantage of imaging is the high throughput analysis of many structural and morphological traits, mathematically derived from these images. The objective of this study was to identify a set of morphological parameters that could be used to differentiate genotypes and/or growth over time. The results suggest that imaging techniques are a powerful tool to differentiate plants based on morphological and physiological parameters. This concept is currently being used in the development of a searchable phenotypic database relating phenotype with genotype. The major challenges for documenting the database will be the standardization of the growing conditions amongst users, the systematic metadata acquisition and the development of a common descriptive language, i.e. an ontology. This will allow the integration of the phenotypic information with other “-omics” datasets.

16. A screening method for salinity tolerance in cereals using infra-red thermography

X.R.R Sirault^1,2, R.A. James¹, R.T. Furbank^{1,2 1}CSIRO Plant Industry, Black Mountain, Cnr Clunies Ross St and Barry Drive, Canberra, ACT 2601, Australia ²Australian Plant Phenomics Facility, the High Resolution Plant Phenomics Facility, Cnr Clunies Ross St and Barry drive, Canberra, ACT 2601, Australia Under saline conditions, plant growth is reduced. This reduction in plant growth is initially due to lower stomatal conductance. As a result, genotypic variation in tolerance to osmotic stress has been assessed by measuring stomatal conductance of plants grown in salt, relative to non-salt controls. Although a reduction in stomatal conductance affect growth, it also decreases transpiration rate. As leaf temperature differences due to variation in transpiration rates can be visualised by infra-red thermal imaging, we used this technology to assess its usefulness in screening for osmotic stress tolerance in barley. The aim of this study was to report on the development of an accurate, fast, high through-put screening protocol for osmotic stress tolerance using infra-red thermography. Barley was assessed under different level of salt concentration (50, 100, 150 and 200 mM NaCl). A long-wave infra-red camera (SC660, FLIR Systems) was used to capture leaf temperature images. The temperature difference between treated and non-treated plant was in the range of 2^OK. Simultaneous gas exchange measurements of leaf conductance were recorded using an AP4 steady-state porometer (Delta-T Devices). We demonstrated that there was a clear relationship between salinity level, stomatal conductance and leaf temperature measured using IR thermography. We then developed a high throughput, automated image analysis protocol for the capture, identification and analysis of thermal images of barley. We concluded that IR imaging is suitable for the screening of large numbers of genotypes varying for stomatal traits, specifically salt tolerance.

17. Measuring shoots and roots simultaneously using non-invasive time-lapse photography

Sirault XRR^1,2, Nagel K³, Walter A³, Schurr U³, Watt M¹, Furbank RT^{1,2 1}CSIRO Plant Industry, GPO Box 1600, Canberra ACT 2601, Australia ²High Resolution Plant Phenomics Centre, GPO Box 1600, Canberra ACT 2601, Australia ³Institute of Chemistry and Dynamics of the Geoshpere, Forschumgszentrum Julich, Germany Access to water at depth is a key drought tolerance trait for wheat breeders, however, few phenotyping systems exist to assay root growth in soil in response to water deficit. Techniques to date have used shoot vigour as a proxy for root vigour. However, genetic variation in root vigour may or may not be linked to shoot vigour and we currently lack a system which can quantitatively measure both these parameters simultaneously. Uncoupling these two parameters in a phenotypic screen is important for development of new germplasm with enhanced drought tolerance. Here we describe a device which can be used to non-destructively assay and screen for both root and shoot growth at the seedling stage in low to medium throughput set-up. The system is composed of three cameras and a mirror to record four images of the plant: two side views, one top view and view of the root system. A software program was developed in Matlab to control cameras and time-lapse sequences. Processing algorithms were also developed to extract plant and root outlines over time. The system is being modified to increase its spatial resolution and also to accommodate other sensing technologies for correlating plant function to plant architecture. Such system is an invaluable tool for studying carbon partitioning in a range of plant species.

18. Green Fluorescent Proteint (GFP) - A tool to identify roots in mixed plant stands

Marc Faget^1,*,Markus Liedgens¹, Juan Manuel Herrera¹, Emmanuel Frossard¹, Peter Stamp^{2 1}ETH Zurich, Institute of Plant Sciences, FEL, Eschikon 33, CH-8315 Lindau, Switzerland ²ETH Zurich, Institute of Plant Sciences, Universitatstr. 2, CH-8092 Zurich, Switzerland ^*To whom correspondence should be addressed. Email: marc.faget@ipw.agrl.ethz.ch Although roots take up most of the resources required by the plant, the lack of efficient research tools hinders the understanding of the root system. This is even more evident when research focuses is not on the single plant but on plants, which share the same soil resources. None of the available methods enables the desired simple, inexpensive, and objective assignement of the observed roots to a target plant in a mixture. Here we demonstrate that transgenic plants expressing the GFP, combined with the minirhizotron technique, are the key to overcoming the methodical limitation to investigate root interactions in situ. We planted transgenic maize (Zea mays L.) together with either its corresponding wild type or Italian ryegrass (Lollium multiflorum Lam.). The fluorescences enables the observation of the relative distribution of the roots of each plant type and, thus, their interaction with each other. The selected plants are suitable for model experiments to unravel fundamental belowground ecological processes. Because the genetic transformation of plants is an established technique, which can be applied to a large set of plant species, this method is of wide scope.

19. “Phenonet” : A Distributed Sensor Network for Field Crop Phenotyping

David Deery, Robert Furbank, Xavier Sirault CSIRO Plant Industry and High Resolution Plant Phenomics Centre Large scale remote phenotyping of field sites with minimal human intervention may be possible with newly developed “intelligent” data logging cards (called “Fleck” cards). The Fleck cards are unique because they can transmit large bandwith data from eight independent sensors, communicate by radio transmission with each other and a base station and are fully programmable by radio transmission. Importantly, the Fleck cards can be programmed to allow intelligent data collection. For example “if air temp drops below 2 deg C or above 40 deg C, log parameter “x” every 5 min, not every 5 hours”. This data capture can be modified remotely through the 3G phone network. A pilot study is underway to deploy a distributed sensor network at the HRPPC field site at CSIRO Canberra to trial the range of measurements made possible by the Fleck system. These measurements and instruments include; micro RGB camera to detect the flowering and senescence profile, canopy temperature, NDVI, photosynthetically active radiation, soil moisture, soil and air temperature, basic meteorology including rainfall, wind, relative humidity, radiation and hail.