Botrytis cinerea is the fungus that causes the grapevine diseases botrytis bunch rot and grey mould. In years conducive to disease development, substantial economic loss can occur from a reduction in yield and a downgrade in fruit quality. Managing Botrytis can be a challenge because many factors contribute to infection and disease development. This page presents a range of resources to help growers understand and manage this fungus. The links provided are intended to inform the Australian grape and wine sector and should not be interpreted as an endorsement of any product.