Biotypes, defined by Dr Ian D’Agata (2014, p567) as grapevines which looked so different to non-expert eyes they were considered distinct varieties. A biotype is a grapevine which is genetically identical to others but nevertheless ‘presents enough morphological (the study of the form and structure of organisms and their specific structural features) and behavioural diversity to be viewed as a separate subvariety of the same family.’

Bibliography

Dr Ian D’Agata, Native Wine Grapes of Italy (University of California Press, 2014).