Pesticide Usage in Scotland: Arable crops and Potato stores 2022

2022 Potato storage and pesticide usage

Seed potatoes

• An estimated 332,745 tonnes of seed potatoes were stored in Scotland in 2022, compared with an estimated 391,208 tonnes stored in 2020
• 78 per cent of seed potatoes were stored in refrigerated stores and 22 per cent in ambient ventilated stores (Figure 5)
• All seed potatoes sampled in 2022 were stored in boxes
• Overall, 25 per cent of seed potatoes received a pesticide treatment in store
• The percentage of seed potatoes receiving an in-store pesticide treatment was 53 per cent in ambient ventilated stores and 17 per cent in refrigerated stores (Table 1)
• The fungicide imazalil was the only active substance encountered in seed potatoes (summary below)
• Imazalil is applied as a spray to tubers
• Reasons for use were supplied for 95 per cent of the crop which was treated with fungicides. General storage diseases was the only reason supplied

Summary of estimated pesticide use on seed potatoes in store:

Ware potatoes

• An estimated 618,449 tonnes of ware potatoes were stored in Scotland in 2022, compared with the estimated 596,407 tonnes stored in 2020
• 82 per cent of ware potatoes were stored in refrigerated stores, 17 per cent were stored in ambient ventilated stores and less than one per cent in unventilated stores (Figure 6)
• All ware potatoes sampled were stored in boxes
• Eight per cent of ware potatoes received a pesticide treatment in store
• The percentage of ware potatoes receiving an in-store pesticide treatment was seven and 14 per cent in refrigerated stores and ambient ventilated stores respectively (Table 1)
• One fungicide (imazalil) and three growth regulators (ethylene, spearmint oil & 1,4-dimethylnaphthalene) were encountered in ware potato stores (summary below)
• Imazalil is applied as a spray to tubers. Ethylene is applied as a gas, spearmint oil and 1,4-dimethylnaphthalene are applied as a fog to stores
• Reasons for use were supplied for less than 0.5 per cent of the crop which was treated with fungicides. Storage diseases was the only reason given
• The only specified reason for use of growth regulators was sprout suppression

Summary of estimated pesticide use on ware potatoes in store:

(1) This formulation is not approved as a plant protection product for stored ware potatoes. Refer to Pesticide usage – Ware potatoes section for details.