We have been also testing different natural product-based strategies (essential oils, diatomaceous earth, zeolites,…) against stored product insects. Excellent results were achieved by using wood ash from three different tree species (Norway spruce, common beech, black locust) against maize weevil. Our work within project Applause has been focused also on testing eight (Japanese knotweed, Bohemian knotweed, Canada goldenrod, giant goldenrod, stinkwort, tree of heaven, staghorn sumac, false indigo) different invasive alien plants against harmful organisms of cultivated crops. We have been mainly testing the efficacy of water extracts, but against slugs and stored product insect we have tested efficacy of plant powders (crushed leaves). The most promising results were achieved when water extract from false indigo and tree of heaven as home-made formulations were used against insects on onion and cabbage, and also against phytophagous mites on bean. Research, entitled »First results on potential insecticidal activity of plant powders of invasive alien plants against rice weevil under laboratory conditions«, authored by research fellow Dr. Tanja Bohinc and prof. dr. Stanislav Trdan, has been acknowledged as best poster presentation at 12th International conference of the IOBC/WPRS Working Group on the integrated protection of stored products in Pisa (Italy).
Experiment on buckwheat, where we have tested impact of spraying with water extracts from invasive alien plants on pollinators and beneficial organisms (photo: Tanja Bohinc)