MODEL RELEASED. Genetically modified crop. Resea- rcher studying genetically modified rape plants in a field. Rape (Brassica napus) is grown mainly for its oil. Genetic modification of plants involves altering their DNA (deoxyribonucleic acid), the substance which contains the genetic code that describes every feature of the plant. By altering the DNA, different features can be incorporated into the plant. In this case, a gene from another species has been introduced into the rape's DNA (transgenics). This confers resistance to a specific herbicide, which can then be sprayed on the field to kill all other plants. Photographed in Kings Lynn, England.