In the present study, a new method for a decision-support system for fungicide administration against the pathogen Botrytis cinerea in vineyards was developed based on Integrated Pest Management principles which identified an infection risk before the appearance of disease symptoms. The proposed method is based on the combination of (i) the phenological observations of the main susceptible stages to infection, (ii) the airborne spores monitoring, (iii) the forecasting of the suitable meteorological conditions for B. cinerea spore germination during the subsequent 4–6 days after the spore detection. Aerobiological, phenological and meteorological analyses were carried out using data from 2008 to 2015 in a vineyard of Northwestern Spain. Aerobiological spore data were obtained using a Lanzoni VPPS-2000 pollen-spore trap. Phenological observations were conducted on 22 plants of Treixadura cultivar following the BBCH (Biologische Bundesanstalt für Land und Forstwirtschaft, Bundessortenamt und CHemische Industrie) scale. The Magarey generic fungal model was applied for the identification of the main meteorological suitable periods for infection within the susceptible phenological stages of flowering and ripening of berries. Our results showed that climatic conditions favoured fungal development during flowering, although a higher incidence of B. cinerea infection risk-periods occurred during the prior-to-harvest stage of ripening of berries, the most susceptible phenological stage to B. cinerea infection obtained by the proposed methodology. This approach enables more precise targeting in pesticide spraying and reduction in pesticide application from 4–5 to 2–3 times per year at our commercial study. It also illustrates the real-world benefits of integrated disease risk modelling.

Mid-Atlantic wine consumers participated in an Internet survey to determine which of three attributes (retail base prices, Botrytis cinerea [bunch rot] control measure, or weed-control strategy) and attribute levels (e.g., a retail base price of $12, $16, $22, or $26) were the most important factors in their decisions to purchase 750mL glass bottles of wine. Conjoint analysis was used to calculate average importance for the three attributes. Based on these calculations, the base retail price attribute had the greatest impact on participants’ decision to purchase the wine (57.40%), followed by bunch rot control measure (20.76%) and weed control strategy (21.49%). Participants were also asked to indicate how interested (not at all interested to extremely interested) they were in purchasing wines produced from grapes grown using minimal pesticides or with cover crops to control weeds. Separate conjoint analyses were then performed based on participants’ level of interest in the two sustainable production methods. In both instances, the average importance values for retail base price were still higher than the values for either bunch rot or weed control strategies. Average importance values for price were lower for participants who responded that they were “very” or “extremely interested” in purchasing wine produced with minimal pesticides or with cover crops than for participants who were “not all interested” in purchasing such wines. (JEL Classifications: Q18, Q11, M31)

Introduction. Litter on the ground is a primary source of Botrytis cinerea inoculum in boysenberry (Rubus hybrid) gardens. The effect of litter management on primary inoculum production, and flower and berry infections was determined. Materials and methods. A series of experiments ranging from laboratory to large-scale field evaluations were conducted in New Zealand during 1997-2002 to evaluate litter management options for control of B. cinerea. The laboratory trial investigated the effect of litter size (shredded vs. unshredded litter) and debris amendments on tissue degradation and B. cinerea colonization. The field trial (four sites) investigated the effect of litter amendments (compost, urea and fungicide) and piling litter on B. cinerea sporulation. In the 4-year commercial-scale study (three properties), the effect of litter treatment (piling, compost and microbial extracts/suspensions) on primary inoculum, flower and berry infections was assessed. Results and discussion. The laboratory trial showed that bark + sewage sludge compost amendment enhanced litter decomposition and reduced B. cinerea sporulation on infected tissue after 8 weeks. The field trial indicated that piling of shredded boysenberry debris was more important than litter amendments in reducing the amount of B. cinerea harbored within the litter. Commercial field-scale evaluation of litter management options verified that piling of shredded litter is the most important step in B. cinerea inoculum control from debris. It also showed that microbial litter amendments (compost, solutions or extracts) can be beneficial. While B. cinerea inoculum control also reduced the amount of flower infections, berry infections at harvest were not affected, indicating that other sources of B. cinerea inoculum contribute to berry infection post-flowering.