Brassica seeds are important as a basic unit of plant growth and sources of vegetable oil.Seed development is regulated by many dynamic metabolic processes controlled by complex networks of spatially and temporally expressed genes.We conducted a global microarray gene co-expression analysis of developing seeds from two diverse morphotypes of B.rapa,a Pakchoi and a yellow sarson,and two of their DH progeny.Most transcriptional changes occured between 25 and 35 days after pollination.