Breeding for insect resistance in oilseed rape: Challenges, current knowledge and perspectives

Dealing with insect pests is one of the biggest challenges facing the cultivation of oilseed rape (Brassica napus, OSR). Insect pests are usually controlled using insecticides, but the increasing occurrence of insecticide-resistant populations and the socio-economic context argue against the sole use of these substances. Plant resistance is a classical and proven alternative crop protection strategy that is the basic tool of integrated pest management. However, no insect-resistant OSR cultivar is currently available on the market. Here, I review some of the constraints that make phenotyping for insect resistance particularly challenging with OSR and give perspectives to develop this resistance. Some studies have proved that breeding OSR for insect resistance could be achieved, and three strategies have been considered: introducing resistance transgenes into the OSR genome, exploiting natural variation in resistance already present in B.napus and introgressing resistance from other brassicaceous species. The white mustard, Sinapis alba, seems a particularly promising source of resistance against most of the OSR insect pests.