The fungus Sclerotinia sclerotiorum,one of the most important plant pathogens,causes white mold of many plant species with enormous losses in a variety of economically important crops including Brassica napus(rapeseed).The interaction of necrotrophs with their hosts is more complex than initially thought,and still poorly understood.In this study,transcriptome sequencing was used to identify the S.sclerotiorum genes that were differentially expressed during infection of the leaf of B.napus.