Crop Specific Safety Concerns Rapeseed

Every crop has a different relationship to the environment, which means environmental impact assessments must be conducted on a case-by-case basis. Different crops pose different threats when it comes to out-crossing or escaping cultivation. The following plant specific characteristics are taken into account for risk assessment.

General information

Rapeseed, also known as oilseed rape or canola, is believed to have originated in the Mediterranean area. Rapeseed is widely grown as forage for livestock and as an oilseed. Rapeseed oil is used for industrial purposes and for food. Leftovers from oil production are called “rapeseed cake”, which is used as livestock feed. Rapeseed is cultivated in temperate regions.

Is out-crossing of transgenes from rapeseed possible?

Rapeseed (Brassica napus L. ssp. oleifera) has several potential crossing partners. Crosses between rapeseed and close relatives such as other rapeseed plants, turnip rape (B. rapa) and Indian mustard (B. juncea) have been observed under field conditions.  Turnip rape is a particularly likely candidate for gene transfer.

Crosses with with other related species (B. nigra, B. carinata, Sinapis sp., Hirschfeldia incana, Diplotaxis sp., and Erucastrum gallicum) have not been seen under field conditions. Hybrids with wild mustard (Sinapis arvensis) and hoary mustard (Hirschfeldia incana) do occur, although very infrequently. Such hybrids have been produced under artificial conditions, but in most cases, the offspring have low fertility.

Rapeseed is predominantly self-pollinated (approx. 70%). Pollen dissemination (approx. 30%) occurs by wind and insects (mainly bees), depending upon weather conditions and water availability. Pollen tends to travel only short distances (approx 0.1% reaches 50m).

Can rapeseed survive in the environment?

Rapeseed is short-lived, surviving mainly via seeds. Volunteers (re-growth of seeds dropped in the field) are often seen in fields where rapeseed was once grown. In most cases, volunteers are easily controlled by herbicides. In addition to the use of herbicides, agricultural methods to reduce seed dormancy and survival in the soil seem to be effective, e.g. fallowing after harvest or tillage.
Besides the occurrence of volunteers, seeds may be spread by machinery or animals like birds or insects. Therefore, volunteers may also occur at the edges of fields and along roadsides and railways. Survival and establishment of rapeseed is unlikely in undisturbed habitats.