Implementation of a New Oxygenate Treatment Against Fungal Diseases in Viticulture
Pascal Wegmann-Herr,* Maren
Scharfenberger-Schmeer, Andreas Kortekamp, Lea Stahl, and
Friederike Rex
*Institute for Viticulture and Enology (DLR-Rheinpfalz),
Breitenweg 71, 67435 Neustadt, Germany
(pascal.wegmann-herr@dlr.rlp.de)
Over the last decades the use of pesticides such as copper in vine protection has come under severe discussion and restrictions, causing concern in viticulture. Since the efficacy of oxygenates against various microorganisms has been proved in the medical field, a strategy for oxygenate-based plant protection was developed. Treatments of vineyards with classical O3 has shown to be not effective due to the short reaction time. We examined a longer-lasting, effective oxygenate treatment to reduce harmful environmental pesticide residues. The production of the oxygenate is following the Criegee-mechanism using O3 and natural, plant-derived unsaturated fatty acids forming so called ozonides. Therefore the effect of the treatment was evaluated in a holistic approach, covering its efficiency against fungal diseases, protection of desired beneficial insects, the micro flora, and various secondary metabolites of the grapevine, such as aroma precursors and the resulting sensory profile of the wines. The biological efficacy was measured over three years using different in vivo and in vitro studies. The influence on desired berry compounds such as anthocyanins, glutathione, or aroma precursors was determined by classical gas chromatography-mass spectrometry and high-performance liquid chromatography methods. Positive effects against downy and powdery mildew were demonstrated. No negative effects against insects, naturally occurring microorganisms, or desired berry compounds was observed. Even spontaneous fermentation was not inhibited. Quantitative descriptive sensory analysis and CATA showed no negative effect of the treatment. In viticulture, the use of oxygenates could lead to a reduction in the use of copper-based pesticides and lower soil contamination with pesticide residues.
AIF/ZIM Funding together with ANSEROS company Tübingen ZF4528001SA7
