Research

Computer vision and digitalization are becoming impactful tools in precision agriculture. In these fields, object detection using deep learning technologies has many potential applications, one of them is the automated detection of toxic weeds, which threaten food safety. This PhD study develops a methodology to automatically detect toxic weed species such as different Senecio species, which contain highly toxic pyrrolizidine alkaloids (PAs). Various multispectral cameras and camera platforms, with a focus on aerial drones, are used to achieve this task. Vision transformers and other detection models optimized for edge computing will be used to determine whether it is possible to differentiate different Senecio and other weed species. Field surveys will be conducted in Lower Austrian herb and spice fields using high-resolution UAV imagery to capture phenological variability and environmental conditions. Through interviews and surveys with Lower Austrian farmers, this study will investigate the priorities, considerations, and practical implications of automated toxic weed detection. The developed pipeline aims to reduce PA contamination, minimize resource waste, and support compliance with EU guidelines. Additionally, this study's methodology could be applied to broader applications in sustainable crop management and food safety, such as detecting other weeds, or plant diseases.

The portfolio of active substances for plant protection products available in the European Union is currently undergoing massive change. While the number of approved active substances has remained roughly the same in recent years, there has been a shift from chemical active substances to microorganisms and other biological active substances, such as plant extracts and pheromones. The background to this development is the constant adaptation of testing methods to new findings and the state of the art in science, as well as the consideration of additional criteria in the approval of active substances (e.g. endocrine properties). This is also intended to support the goal of a sustainable food system within the framework of the European Commission's ‘Green Deal’.While sufficient alternatives are still available for some of the chemical active substances that are no longer approved, lengthy negotiations on individual active substances in the Standing Committee on Plants, Animals, Food and Feed, as well as experience from agricultural practice, show that some chemical active substances are difficult or impossible to replace. Based on the currently established assessment methods, it is already to be expected that further chemical substances will not be approved. In addition, it can be assumed that further findings regarding possible negative effects on human health and the environment will result in individual active substances and even entire groups of active substances losing their approval in the medium term. For example, the problem areas of per- and polyfluorinated alkyl substances (PFAS), succinate dehydrogenase inhibitors (SDHI) and the increase in resistance in the medical sector due to azole active substances, but the new CLP criteria (Classification, Labelling and Packaging) and adaptations to the Drinking Water Ordinance could also influence the availability of PPP active substances. As part of the project, an assessment will now be carried out, taking into account the currently valid evaluation criteria as well as already known future developments and requirements at European level, to determine which active substances may no longer be available in the medium term. After analysing the potential treatment gaps, possible alternatives will be discussed and evaluated in terms of the state of the art, practicability and effectiveness, relevance for Austrian agriculture and the time horizon for future application and implementation.

The onion thrips Thrips tabaci Lindeman (Thysanoptera: Thripidae), favoured by increasing heat and drought, is a problem pest in summer onion crops in the vegetable growing regions of eastern Austria. A natural antagonist is the predatory thrips Aeolothrips spp. If present regularly and in sufficient numbers, it has the potential to sustainably reduce T. tabaci populations in onions. Habitat management is promising in this context: flower strips with a mix of functionally appropriate flowering plants can make arable land attractive and favourable for Aeolothrips spp.. A prerequisite for the success of this control strategy is the clarification of previously unanswered questions regarding the occurrence, behaviour, population development and predation rate. Identifying the most common species of the genus Aeolothrips and the flowering plant(s) on which these predatory thrips are found is of fundamental importance. The attractiveness of the flowering plants and onion plants infested with T. tabaci to Aeolothrips spp. will be investigated under laboratory conditions, as well as their predation rate on infested onion plants. A field trial comparing population dynamics and development of pest and beneficial in summer onion with specifically designed annual and biennial flowering strips will evaluate the potential of habitat management for biological control of onion thrips.