In planta transformation of Brassica rapa and B. napus via vernalization-infiltration methods

_In planta_ transformation has been widely used for gene transfer in the model plant Arabidopsis.Unlike Arabidopsis, the genus Brassica that comprises many important vegetable, oil seed and weed crops are vernalization-required, cross-pollinated, and self-incompatible.The protocols for _in planta_ transformation established for Arabidopsis are not directly applicable to these crops.We take advantage of Arabidopsis vacuum in ltration to establish vernalization-in ltration method for transformation of Brassica crops.The germinated seeds of Chinese cabbage and oilseed rape are exposed to cold treatment for a period of vernalization; the oral buds of the early in orescences are opened by hand before Agrobacterium infection; Agrobacterium-infected in orescences are in ltrated with vacuum; the transformed stigmas are pollinated with the non-infected pollens of siblings; and hygromycin resistance is used to select the transformants.Using the vernalization-in ltration method, we have identi ed 52 homozygous transgenic lines from the cultivars of Chinese cabbage and oilseed rape.