Temporal dynamics of pesticide use in three field vegetable crops with respect to sowing date and degree days

ABSTRACT

We analysed the timing of pesticide treatments for eventual analysis of temporal environmental risks associated with pesticide use in field vegetable crops. At the same time, we investigated whether farmers followed the Integrated Pest Management (IPM) instructions. The data cover chemical plant protection in field vegetable farms in southwestern Finland in 2009–2019. The timing of treatments, made with different pesticides in the weeks following sowing, corresponded with the known phenology of different pests of carrot, swede and fresh pea. The same was true for the carrot fly, the pea moth and the second generation of the cabbage root fly when phenological flight time models using historical data were used to predict the timing of treatments. We conclude that farmers acted in accordance with the principles of IPM when practising chemical control. For those species that lacked phenological predictive models in the study years, the degree days for the observed timing of treatments can be used as a starting point if such models are developed in the future. Our results can be used as a long-term baseline in future surveys on the changes in pesticide use and their risks regarding the studied crops.

KEYWORDS:

• Carrot
• swede
• fresh pea
• insect pests
• plant protection product (PPP) use
• chemical control

Acknowledgements

We thank Apetit Ruoka Ltd. for the excellent data and good cooperation. The company gave confidential rights to the Natural Resources Institute Finland (Luke) to use its data (agreement 2703/12 01 01 06/2019 between Luke and Apetit Ruoka Ltd.) for the current and previous study. We are grateful for the financial support (42660) of Maa- ja Vesitekniikan Tuki ry. for this study. We owe a dept of gratitude to our good colleague Dr. Asko Hannukkala who kindly helped us with the data and supervised the work. This publication is published posthumously for him. We would also like to thank the following researchers at Natural Resources Institute Finland (Luke): Mr. Pentti Ruuttunen, Dr. Anne Nissinen, Dr. Erja Huusela-Veistola and Mr. Lauri Jauhiainen for sharing their expertise on the pests and their control and prediction models. We also thank Docent Jonathan Robinson for language revision.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Maa- ja Vesitekniikan Tuki ry (42660).

Notes on contributors

Kati Räsänen

Kati Räsänen is a Ph.D. student and a research scientist at Natural Resources Institute Finland (Luke). She is working with issues on pesticides and integrated pest management (IPM).

Janne Kaseva

Janne Kaseva is a senior scientist at Natural Resources Institute Finland (Luke) and his special competence is on statistical methods.

Marja Aaltonen

Marja Aaltonen is a research scientist at Natural Resources Institute Finland (Luke) and working with open field vegetables and vegetable cultivation techiques.

Irene Vänninen

Irene Vänninen is a senior scientist at Natural Resources Institute Finland (Luke). Her projects are related to integrated pest management and development of the horticultural sector. Her special competence is horticulture, plant health, plant protection, greenhouse vegetables, greenhouse ornamentals, biological control, ecology, pest insects and mites, knowledge management and change management.