The main aim of my group within the department of phytopathology is the detection and identification of plant diseases through the use of optical sensors. Optical sensors, with a focus of multi- and hyperspectral imaging, have been shown to be able to detect and differentiate between plant pathogens in early stages of infection through distinct changes in the reflectance profiles of plants, which could be linked to changes in plant metabolism and cellular structure under biotic and abiotic stresses.

Currently, our main goals are the investigation of new pathogens and plant species on laboratory and greenhouse scale, as well as the transition to field scale measurements in order to develop methods which can be applied in agriculture. Especially the steps to practical applications of disease detection with optical sensors for field monitoring have proven to be difficult in the past, as a high data variability through uncontrollable environmental factors poses unique challenges compared to laboratory and greenhouse scales.

In order to overcome these challenges and provide high throughput measurements a combination of UAV-based measurements with optical sensors and advanced data analysis pipelines has been established and is being developed further within the workgroup. These goals are achieved through multiple national research projects, such as FarmingIOS, NOcsPS and DiWenkLa, in which multiple partners from universities and companies work together to invent practical solutions for field applications of optical sensors for improved monitoring, precision farming, data integration and biological plant protection alternatives.

Thomas, S., Behman, J., Steier, A., Kraska, T., Muller, O., Rascher, U. and Mahlein, A-K. (2018) Quantitative assessment of disease severity and rating of barley cultivars based on hyperspectral imaging in a non-invasive, automated phenotyping platform. Plant Methods, 14, 45.

Thomas, S., Kuska, M. T., Bohnenkamp, D., Brugger, A., Alisaac, E., Wahabzada, M., Behmann, J. and Mahlein, A-K. (2017) Benefits of hyperspectral imaging for plant disease detection and plant protection – a technical perspective. Plant Dis Protec, 125, 5-20.

Thomas, S., Wahabzada, M., Kuska, M., Rascher, U. and Mahlein, A-K. (2017) Observation of plant–pathogen interaction by simultaneous hyperspectral imaging reflection and transmission measurements. Funct Plant Biol, 44, 23–34.