Use of Information Technologies for Precision Crop Protection

Computer-aided diagnosis and prognosis models have been used for management decisions in plant protection. Initial infestation rate, temperature and leaf wetness are important parameters for these decision models. So far, in-field variability and sometimes variability between fields have not been taken into account for management decisions.
The pathogenisis of the fungal pathogens Puccinia recondita causing leaf rust and Septoria tritici causing speckled leaf of wheat depends on specific climatic conditions.
Portable wheatstations, monitoring leaf wetness, air temperature and relative humidity at discrete spots in a wheat field showed various variations of these microclimatical parameters. However the limiting factor of these measurements is their restriction to a the location of the sensor. Spatial information can hardly be derived. Therefore his study is aimed at the employment of an imaging thermography system (Varioscan 3021, Jenoptik, Jena) as a tool to monitor the microclimatic conditions whithin a wheat field with a high spatial resolution of (320 x 240 pixels). Experiments were conducted on the recognition of leafwetness on a single leaf scale and a crop canopy of the size of 1m2 in a greenhouse (left picture). In-field studies focused on comparing the content of groundbased and air-borne thermographic data (right picture) and linking these to ground-truth data.