Given this background, the PURE research project (‘Innovative crop protection for sustainable agriculture’) had teams dedicated to first identifying the most critical pests and diseases in European grapevine systems, followed by the production of IPM solutions. These candidate solutions were then tested in both on-station and on-farm experiments, field-tested solutions were assessed and compared, and measures taken to stimulate and promote their uptake. This large package of work is now available on the PURE website in the form of booklets, deliverables and e-learning material.

The IPM solutions and innovative control methods tested were based on a number of approaches, including Decision Support Systems (DSS), microbial biocontrol agents (biopesticides), reduction of overwintering disease inoculum, agronomic practices and resistant varieties. These solutions have been designed for three diseases - grey mould (Botrytis cinerea ), powdery mildew (Erysiphe necator ) and downy mildew (Plasmopara viticola ) - and two insect pests (European grape berry moth (Lobesia botrana ) and vine mealybug (Planococcus ficus ).   

Botrytis cinerea (grey mould). Copyright: Anne-Sophie Walker, INRA

For example, for grey mould, trials were conducted using biofungicides based on three microbial biocontrol agents and through agronomic measures based on summer pruning. Though disease pressure was low during the four years of trials in Italy, researchers concluded that each of the microorganisms tested was effective, though a broader uptake is restricted by the fact that these biocontrol agents are not available in every country.  They also caution that environmental conditions during spraying are important as they could negatively influence the survival and subsequent efficacy of microorganisms. Pruning trials were successfully conducted under high disease pressure conditions in Germany, with researchers concluding that defoliation at the phenological stage of flowering was as effective as three fungicide treatments.   

For powdery mildew, researchers conducted trials based on the application of a hyperparasite called Ampelomyces  (available commercially as the AQ10 biofungicide in some European countries) to reduce overwintering powdery mildew inoculum. One of the challenges of this approach is to time the applications correctly as parasitisation is only partial once the chasmothecia (overwintering inoculum) reaches maturity. While this method reduced the severity of primary powdery mildew infections in most of the study areas, there was an exception. In Germany, chasmothecia formation started in June and continued until the end of season, so Ampelomyces applications at around harvest time were on mature chasmothecia and ineffective.

Regarding Decision Support Systems, a DSS called vite.net developed by Italy’s Università Cattolica del Sacro Cuore was used to schedule fungicide applications against powdery and downy mildews. Two strategies (baseline and innovative) were compared across nine Italian farms and the latter produced improvements in environmental quality alongside efficient disease control and significant reductions in disease management costs.

Lobesia botrana. Copyright: Remi Coutin and Nicole Hawlitzky, INRA

For control of the grape berry moth (Lobesia botrana ), the effects of natural pesticides (Bacillus thuringiensis (Bt ), azadirachtin, Beauveria bassiana , spinosad and pyrethrins) were evaluated in two experimental vineyards in Italy. From this work, researchers concluded that this strategy requires accurate monitoring of L. botrana  phenology (in particular oviposition) to identify the best time for applications, and that attention should be given to the formulate (date of production and conservation), weather conditions, water quality (pH) and volume to ensure maximum contact with the berries. They noted that while Bt does not control other grape pests, it is the most selective among natural pesticides.

Finally, researchers designed various prototype low-input grapevine cropping systems based on the use of DSS, biocontrol and resistant varieties, which were then assessed for their performance and sustainability in a network of experimental stations in three different regions of France. Two DSS were used (Mildium to regulate the number of applications against downy and powdery mildews and Optidose to adjust pesticide dose according to canopy development) and in all cases were effective in reducing pesticide use and the associated environmental risk. Strategies based on resistant varieties also suppressed pesticide use and environmental risk, while the strategy based exclusively on the use of biocontrol reduced risk but raised production costs and severely reduced the gross margin.

PURE information available on grapevine

For more information:

• Visit the PURE website
• To read more about PURE’s grapevine work, click here