Study to optimize the effectiveness of Copper treatments for a low impact viticulture

Among all pathologies that afflict grapevine, Downy Mildew (DM) is the most important. Generally controlled by using Copper (Cu), recently European Commission confirmed its usage but limiting the maximum amount to 28 Kg per hectare in 7 years (Reg. EU 2018/1981). Anyway, in the grape growing context it is difficult to reduce the use of Cu and generally chemicals, due to climate conditions, as well as climate changing. For this instance, Cu treatments have to be improved. Hence, the aims of this work were to determine the possibility to reduce Cu using and evaluating the variation of Cu cladding on grapevine leaves and grapes, in relation to the phytoiatric status. The efficacy level of the Cu protection given to DM and the correlation among them was also assessed. Five organic vineyards located in north-eastern of Italy were selected as experimental sites. Leaves and grapes were sampled during vegetative season and analysed for determining the quantity of elemental Cu by the use of ICP AES. Spreading of DM in vineyards was evaluated as well and the correlation between DM and Cu quantity on leaves and grapes was determined. First results indicate that the mean level of Cu applied by farmers (range: 3.77 to 8.88 µg/cm 2 of Cu on leaves) during vegetative season is not enough to have an optimal protection against DM (diffusion on grapes and leaves: 40 to 50%), although at the maximum amount of Cu, the plant protection effect was quite good. Thus, Cu treatments have to be pondered on the basis of meteorological data and previous infection of DM, so that it will be possible to determine the right quantity of Cu to be applied in correlation to DM presence and weather. As future goals, data will be correlated with image analysis, in order to quickly study the best conditions for Cu application directly on field and having back a real time information of Cu cladding and risk classes of DM infection. In this way, it is possible to reduce inputs in plant defence and then guarantee a quality and sustainable production of grapes, wines and must

A multi-indicator approach to compare the sustainability of organic vs. integrated management of grape production

Sustainable agricultural practices are increasingly becoming a strategic asset for global and national environmental policies and economy. A big challenge is the selection of appropriate indicators to describe the complexity of the agroecosystem management. In the present work, the sustainability of grape production, in vineyard trials of Pinot blanc and Rhine Riesling, managed with integrated (INT) and organic management (organic, with cattle manure ORG1 and organic with green manure ORG2), was compared using a multi-indicator approach. The experiment was set in 2011 (1.5 ha in Trento, Italy) and carbon footprint (CF), nitrogen footprint (NF), water footprint (WF), soil microbial diversity (alpha diversity of bacteria, fungi, oomycetes communities) and soil C stock change, were evaluated in 2018. The CF was 0.213—0.227 kg CO2-eq/kg in the INT, 0.144—0.168 kg CO2-eq/kg in ORG1 and 0.134—0.147 kg CO2-eq/kg in ORG2. The NF was around 1 g Nr/kg for the INT, 0.4 g Nr/kg for ORG1 and 0.5 g Nr/kg for ORG2. The WF, excluding the pesticides impact on grey water, was 666—708 L/kg for INT, 605—655 L/kg for ORG1 and 529—580 L/kg for ORG2. The impact of farming practices on soil microbial alpha diversity showed no significant difference among treatments for oomycetes and significantly higher indexes for fungi and bacteria in the ORG1, with INT and ORG2, being similar. No difference in bulk organic C were observed among treatments. Overall, the multi-indicator approach allowed to demonstrate that the organic management was more beneficial for most of the environmental spheres of the agroecosystem compared to integrated management, without affecting the grape yiel

Study for the development of a rapid and non-destructive method for copper analysis in vineyards towards a precision fungal defense strategy

In the defense against downy mildew, copper is still widely used, particularly in organic management. At any rate, specific investigations are needed to significantly reduce the use of copper and minimize its environmental impact. This study, conducted in several farms in Friuli-Venezia Giulia (Northeast Italy), aimed to evaluate the concentration of copper on leaves in various climatic conditions, in order to create an important database for the development of a rapid control system through image analysis. The tests involved sampling leaves and grapes from bud break until the last treatment with copper-based products. After copper recovery using a nitric acid solution, the copper values were analyzed via ICP-AES analysis. Cuprotesmo imprints were also made on the same leaves to develop an application (APP) capable of quickly and non-destructively detecting copper on the leaf surface through image analysis. The analytical data revealed significant correlations between image analysis and copper values only in certain situations involving adult leaves. However, due to the variability in treatment situations, the use of the APP with image analysis for all copper defense scenarios is not yet feasible. Nevertheless, the results are encouraging and will serve for further extensive investigations to develop an image analysis system capable of detecting truly active copper and optimizing pesticide treatments for a precision defense strategy. This strategy aims to ensure low environmental impact, production sustainability, and grape quality