Adoption Dynamics of Fungus‐Resistant Grapevine Varieties: A Real Options Approach

Viticulture is a key economic sector in Europe, but responsible for vast amounts of fungicide use. Fungus‐resistant grapevine varieties are less susceptible to fungal diseases, reducing fungicide use by up to 80%. However, their adoption remains limited, despite their economic and environmental advantages. We develop a bio‐economic simulation model with a real options investment perspective to analyze farmers’ decisions to adopt resistant varieties, accounting for different risk factors (e.g., production, market, policy). We apply the model to the case of Swiss viticulture. Results indicate that in the short‐term, adoption barriers persist for the majority of farmers, with replanting occurring only when favorable conditions are met, such as low discount rates, high disease pressure, and available price premia. Conversely, we find that in the long‐term, as vines reach replacement age, resistant varieties are favored over traditional ones. Our findings further indicate that increases in disease pressure, for example, due to climate change, are likely to accelerate the early adoption of fungus‐resistant varieties. We highlight potential avenues for improving current support for replanting in Switzerland, for example, through market access and information provision. By integrating risk and managerial flexibility into a dynamic, real options decision‐making framework, this study provides new insights for designing effective policies to promote sustainable pest management in viticulture.