resistant populations of oilseed pollen beetles are now widespread19 and resistance in cabbage stem flea beetles20 is becoming more common. 27.8% of the oilseed crop is now treated three or more times with herbicides, compared to 10.8% in 2000. The area of oilseed crop that receives no herbicide treatment at all has fallen from over 35% in 2000 to 5% in 2013. Herbicides used on oilseed rape before and after sowing in autumn are among the principal causes of water quality standard failures (see section 2.2.3). The area of oilseed crop treated with molluscicide has doubled, from 0.19 million ha in 2000 to 0.38 million ha in 2013.
No noticeable decrease in pesticide treated area on other crops
19 20
The maize area, almost all planted to forage maize with a very small area of sweetcorn, has expanded from 2% to 4% of the UK cropped area between 2000 and 2013. Correspondingly, the fungicide- and herbicide-treated maize area has almost doubled over the same period. Potatoes are the crop with the highest intensity of pesticide applications in the UK, primarily due to the very high frequency of fungicide applications. The UK potato area declined from 4% to 3% of the UK cropped area between 2000 and 2013. Over the same period, the pesticide-treated potato area in Great Britain has increased from 3.5 million ha to 4.5 million ha. The sugar beet area has declined from 4% to 3% of the UK cropped area between 2000 and 2013. Over the same period, the pesticide-treated area of beet crops in Great Britain has increased from 2.43 million ha to 2.67 million ha. Sugar beet receives a high frequency of herbicide applications due to its susceptibility to weeds. Horticulture crops (of which 1% are grown in greenhouses) have remained constant on 3% of the UK cropped area between 2000 and 2013, with a slight decrease in area principally due to the loss of traditional orchards, and a slight increase in vegetables
http://cereals.ahdb.org.uk/media/176640/is18-monitoring-and-control-of-pollen-beetle-in-oilseed-rape.pdf http://www.rothamsted.ac.uk/news-views/update-pyrethroid-resistance-cabbage-stem-flea-beetles
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