Economic Impact of the Introduction and Establishment of Drosophila suzukii on Sweet Cherry Production in Switzerland

Abstract

First detected in Switzerland in 2011, the invasive Drosophila suzukii, spotted wing drosophila, has caused recurring costs for growers of berries and fruit. Recommended management approaches rely on a set of methods, tailored to suit crop requirements under the prevailing local conditions. Control of D. suzukii represents a substantial economic burden for growers, in terms of material, equipment, new infrastructure and extra labour. However, those growers who invest wisely to deliver unblemished produce are rewarded with high payoffs. We present insights from a growers’ survey conducted in 2015 and 2016 to gauge the impact of the introduction and establishment of D. suzukii on Swiss sweet cherry production. The surveyed growers (111 in 2015 and 298 in 2016) observed the recommended surveillance, sanitation and control measures. The use of insecticides (78% and 79% of respondents in 2015 and 2016, respectively) and the harvest of all fruits (93% and 59% of respondents in 2015 and 2016, respectively) were the most widespread methods used to reduce damage. Nearly one-third of the respondents set up enclosure nets. Our economic evaluation of different scenarios provides a quantitative indication of the potentially incurred costs. We argue for enhanced stakeholder involvement to raise the acceptance of integrated pest management practices, and to inform research and outreach by providing insights into the motivations and barriers to adoption.

Cost–benefit analysis of controlling the spotted wing drosophila (Drosophila suzukii (Matsumura)) spread and infestation of soft fruits in Trentino, Northern Italy

“…We assumed a market price of €0.85 m –2 for a net with a mesh not larger than 1.00 mm. As a consequence, an average investment for covering with exclusion nets 1 hectare cost about €8 500, amortized over 10 years . For installation and removal of the nets, we considered an average of 100 h ha –1 of labour, valued at a cost of €7.50 h –1 .…”

Baseline susceptibility of spotted wing Drosophila (Drosophila suzukii) to four key insecticide classes

“…2 Achieving control of this pest has been challenging in a number of cropping systems including strawberries, cherries, caneberries and blueberries. [3][4][5][6] Integrated pest management (IPM) practices that previously relied on targeted insecticide sprays applied in response to pest monitoring have been replaced with prophylactic applications initiated when this fly is present and fruit begin to ripen. 2 This has resulted in a major increase in the number of insecticide sprays applied in these crops.…”

Management strategies against Drosophila suzukii: insights into Swiss grape growers choices

“…Drosophila suzukii (Matsumura, 1931) is an invasive vinegar fly native to Southeast Asia, first detected in the USA and Europe in 2008 . It is a threat to agriculture, infesting thin‐skinned fruit and causing severe economic losses in many regions of the world . The larvae feed inside the fruit, making it unmarketable as fresh fruit markets have a zero tolerance policy regarding D. suzukii infestation .…”