Rapid and efficient screening of phosphinothricin tolerant oilseed rape (Brassica napus) with a novel germination test

A novel screening test is described for the discrimination of transgenic ph osphinothricin tolerant oilseed rape from non transgenic rape seedlings. Th e method is based on the germination of rape seeds on filter paper soaked w ith a 0.005% phosphinothricin solution. Under these conditions inhibition o f seedling development by the herbicide can be observed after 10 days. The germination test gains an advantage over the routinely used herbicide spray ing, because it is rapid, needs little space and allows efficient screening of huge numbers of seeds. The assay has been successfully applied to the s creening of different transgenic and non transgenic rapeseed varieties/line s and has been compared to other methods such as Basta(R) spray test, drop test, ELISA-technique and PCR-amplification of the pat gene. This test allo ws on one hand large screening programmes to monitor the foreign gene in th e environment and on the other quality control of seedlots before market in troduction of herbicide tolerant oilseed rape.