SEED-GERMINATION IN WEEDY BRASSICA-CAMPESTRIS AND ITS HYBRIDS WITH BRASSICA-NAPUS - IMPLICATIONS FOR RISK ASSESSMENT OF TRANSGENIC OILSEED RAPE

We studied the germination behaviour of the following types of seeds: weedy Brassica campestris, oilseed rape (Brassica napus), B. campestri s(female) x B. napus(male), B. napus(female) x B. campestris (male) an d, finally, seeds harvested on B. napus(female) x B. campestris(male) hybrids in open pollination with B. campestris and B. napus. The seeds were germinated in Petri dishes, using three different consecutive tr eatments and assaying the viability of non-germinated seeds with tetra zolium staining. B. campestris seeds varied in the treatment they requ ired in order to germinate and many seeds were dormant, in contrast to B. napus seeds, which lacked dormancy. B. campestris(female) x B. nap us(male) and B. napus (female) x B. campestris(male) seeds both resemb led B. napus being non-dormant whereas seeds harvested on B. napus(fem ale) x B. campestris(male) hybrids were more B. campestris-like in ger mination behaviour. We discuss implications for risk of transgene spre ad from oilseed rape to weedy B. campestris.