Research

Dogs, as reliable partners for humans, are increasingly used as species detection dogs in nature conservation or for searching for invasive species. Thanks to their extraordinary sense of smell, trained sniffer dogs are able to detect even the slightest traces of odor molecules such as volatile organic substances from plants. In this project, we use this ability to search for native and invasive poisonous plants with pyrrolizidine alkaloids (PAs) in herb and spice fields. Regular consumption of PAs can be carcinogenic even in relatively small quantities and, in higher doses, can lead to irreversible liver damage. Even extremely low levels of contamination with PAs from poisonous plants can mean that herbs or spices are no longer allowed to be sold in the EU according to updated EU PA limits for those products. Despite the most careful control, contamination with PAs can occur. In addition to native PA poisonous plants such as common groundsel (Senecio vulgaris), there are also invasive species such as the eastern groundsel (S. vernalis) or the narrow-leaved ragwort (S. inaequidens), which have been introduced from Eastern Europe and Southern Africa, respectively. The changed environmental conditions caused by climate change could mean that these invasive species can increasingly establish themselves in arable crops and could thereby endanger food security. Experienced search dogs are trained to detect these poisonous plants using fresh and dried plant material at different stages of development from multiple origins. At the same time, the volatile organic compounds of these samples are also analyzed in order to be able to estimate how the content and composition of essential oils influences the detection success. In the second year of the project, searches will be carried out in different herb and spice fields in order to determine whether specially trained poisonous plant detection dogs are more efficient in searching for Senecio species than human experts and which environmental factors have the greatest influence on precision, sensitivity and efficiency. The use of detection dogs represents a particularly innovative approach to detect potential poisonous plants as early as possible in order to reduce the use of manpower and the use of weed control measures.

The environmental risk assessment connected with the plant protection product authorisation process needs to predict risks over large geographical areas like the entire EU. However, environmental risks are strongly influenced by several biotic and abiotic factors, which vary in space and time. Therefore, there is an urgent need to develop scenarios representaing the diversity of environmental conditions, landscape structure, agricultural practices, and species distributions in EU. The main task of the Institute of Plant Protection at BOKU is the development of a protocol for the vegetation survey which builds the base for the implementation of the coordinated plant surveys in crops and nearby semi-natural habitats in Europe.

The Green Deal of the EU includes two essential objectives: the reduction of pesticide applications and the conservation and restoration of biodiversity. Pesticide reductions are expected to increase the diversity and abundance of natural enemies of pests and consequently also their biocontrol success. However, the vast majority of natural enemies are arthropods, and their diversity strongly declined in the last decades at a global scale. Among other stressors, climate warming is a major driver responsible for the decline of arthropods. In agroecosystems, arthropods are also confronted with a second stressor: agricultural intensification, defined as the increase of agricultural productivity per unit area. Although these two factors are known to be tightly linked, they are usually analyzed separately. However, they may interact additively or synergistically boosting the negative consequences on arthropod diversity in agroecosystems. Apple is the most dominant fruit species in Austria. A serious pest mite, the red spider mite Panonychus ulmi, was efficiently controlled by predatory mites as natural enemies in the past, but regained nowadays the status of a main pest in Styrian apple orchards. Our main hypotheses for this project are: (i) climate warming reduces mite diversity; (ii) synergistic effects between climate warming and agricultural intensification (e.g. pesticide applications) enhance the negative effects on mite diversity; and finally (iii) the natural enemies (i.e. predatory mites) suffer more from the two stressors compared to their prey (i.e. pest mites), which lead to insufficient biocontrol of pest mites. First, we will sample mites in integrated, organic orchards and extensively managed apple meadow orchards (i.e. no pesticide and fertilizer applications) in Styria during two growing seasons, which allow the evaluation of climate warming and agricultural intensification effects on mite diversity. Additionally, mite diversity in extensively managed meadow orchards will be compared between 1985 (historical mite data are available) and 2024/25, to evaluate only climate warming effects on mite diversity. Second, climate warming may indirectly influence mite diversity via promoting agricultural intensification. For example, the use of fungicides in apple orchards increased because of apple scab incidences in the last two decades in Austria, and predatory mites are known to be highly sensitive to fungicides. Thus, micro-climatic data from apple orchards (1961-2025) will be integrated in a dynamic forecast model for apple scab to evaluate, whether climate warming effects could be a potential driver for higher incidences of apple scab indicating synergistic effects between climate warming and agricultural intensification on mite diversity.