Physiological characters (e.g photosynthesis, plant nutrition and hormonal functions etc) are excellent indicators of many traits (e.g. pest/disease resistance, quality & yield) but are difficult to measure and quantify, especially under field conditions.
Plant-parasitic nematodes have a major impact on global food production with an estimated annual loss of about €110 billion worldwide. Root-knot nematodes (RKN; Meloidogyne spp.) and potato cyst nematodes (PCN; Globodera pallida & G. rostochiensis) have high agronomic impact and are considered high-impact plant-parasitic nematodes. Characterising root phenotypes that confer resistance to root pests and disease is challenging, and involves destructive plant harvesting, and so is understanding the interaction between above ground canopy traits and below ground rooting traits for agri-diagnostics. However, studies have shown that changes in shoot and leaf physiology can provide an indirect indicator of root processes below ground. Infrared thermography (IRT) was recently shown to be a reliable tool for monitoring plant stress in potato by measuring changes in canopy temperature associated with altered stomatal conductance (Prashar et al, 2013; Prashar et al., 2014, Prashar and Jones, 2016). Studies on nematode infestation of plants such as potato (Solanum tuberosum) have also been shown to influence plant physiological parameters. Susič et al. 2018 demonstrated the potential of spectral imaging to detect Meloidogyne spp. infestation, with other examples available in sugarbeet, soyabean and cotton. Thus, it is possible to detect specific (biotic) stresses but difficulties arise when discriminating stresses from different pathogens. Similarly, abiotic stresses e.g. water stress, are more accurately detected, although the differentiation between these stresses is crucial when working with soil properties and below ground traits.
Thus, this project aims to use the relationship between physiological ground truthing parameters and remote sensing techniques in the form of integrated spectral and thermography imaging sensors to accurately detect disease infestation in potatoes and understand its application in reliably discriminating between abiotic drought stress symptoms and biotic stress caused by the nematodes/other root diseases, the reason being a high similarity of above-ground effects caused by both stressors on the plant canopy. With the aim to evaluate sensing approaches, and develop methodology where canopies are assessed as indirect indicators of root phenotypes and to monitor and detect early root stress responses, different physiological traits will be evaluated under both control and field conditions with following objectives in mind.
• Evaluate the utility of high-throughput phenotyping techniques to predict canopy traits and relationship to yield in field conditions.
• Conduct case studies for early disease detection under field scenarios for nematodes.
• Determine the interactions between water use/stress traits and susceptibility to pests/disease and interaction with soil physical properties.
• Determine association between stress response and yields and understand how stress response mechanisms contribute to crosstalk
Location : Newcastle University
How to apply:
All applications musty be submitted to Newcastle University.
Please visit the IAFRI website for further guidance: https://www.ncl.ac.uk/iafri/learning/opportunities/
To apply directly please visit: (ensuring that you note the studentship code. e.g. IAF2001) https://www.ncl.ac.uk/postgraduate/apply/
Prashar, A., Yildiz, J., McNicol, J.W., Bryan, G.J. and Jones, H.G. (2013) 'Infra-red Thermography for High Throughput Field Phenotyping in Solanum tuberosum', PLoS One, 8(6), pp. e65816, 65811-65819.
Prashar, A. and Jones, H.G. (2014) 'Infra-Red Thermography as a High-Throughput Tool for Field Phenotyping', Agronomy, 4(3), pp. 397-417.
Prashar, A. and Jones, H.G. (2016) 'Assessing Drought Responses Using Thermal Infrared Imaging', Methods Mol Biol, 1398, pp. 209-19.
Susič, N., Žibrat, U., Širca, S., Strajnar, P., Razinger, J., Knapič, M., Vončina, A., Urek, G. and Gerič Stare, B. (2018) 'Discrimination between abiotic and biotic drought stress in tomatoes using hyperspectral imaging', Sensors and Actuators B: Chemical, 273, pp. 842-852.
Wheeler, T.A. and Kaufman, H.W. (2003) 'Relationship of Aerial Broad Band Reflectance to Meloidogyne incognita Density in Cotton', J Nematol, 35(1), pp. 48-57.