A SURVEY of the current plantings of winter oilseed rape has shown that nearly four times as much was lost to disease and pestilence than the previous autumn – with the finger pointed at the loss of neonicotinoid seed treatments as a main cause.

Kleffmann Group, a global market research organisation which conducts farmer surveys and panels throughout the world, identified from its GB winter oilseed rape panel this year that there was significant to the planted area, with large regional differences being observed.

Its OSR panel consisted of 403 UK rape growers and it calculated an original planted area in autumn 2018 of 581,030 ha of winter rape. The AHDB early bird survey is consistent with this figure at 582,000 ha. However, 68 farmers reported failed crops, amounting to 6.28% of the total original planted area.

This is 36,000 ha lost and in the 2017/18 season, the percentage loss was just 1.62% so autumn 2018 has been much more hostile to rape survival by a factor of nearly four times.

The farmer survey identified different proportions of hybrid and conventional variety adoption over a number of years. And, for the first time in recent years, it appeared that there was nearly a 50:50 proportion between hybrids and conventional rape varieties being sown on farm (285,000 ha of conventional varieties and 294,000 ha of hybrids).

The survey also showed a clear difference in failed crops by breeding method. In conventional varieties, the area lost was 7.52% (21,000 ha) of the area planted and of the restored hybrid varieties 5.16% of the crop planted (15,000 ha), were lost.

Significant regional differences were also noted. Scotland, for example, had the lowest area of oilseed rape lost at just 0.91% of the original planted area, closely followed by the North-east of England region at 1.36%.

The South-east of England had the highest area of failed crop at 12.60%, followed by Yorkshire and the Humber region at 9.75%. Between these extremes, were the remaining regions – East Midlands suffered 3.5% loss, South-west 4.34%, West Midlands, 5.34% and Eastern, 7.29%. Losses in cropping area have risen in comparison to the year 2018, where the crop failure amounted to just 1.62% of the original planted crop.

Reasons for the crop losses are varied, but do include cabbage stem flea beetle (CSFB) damage, with protective chemistry from neonicotinoids seed treatments no longer permitted and pyrethroid resistance in CSFB adults developing. Poor establishment in some regions and a lack of moisture also hindered germination.

Kleffmann is also using its new digital tool, Crop Radar, which makes it possible from processed satellite imagery to identify the development of cropped area throughout the season. This analysis can be provided at a country, regional or postcode level. Clients are also able to define specific regions of interest for further analysis.

Using this, it said it will continue to monitor the situation and review images for an assessment in mid-March.