Studies on the Fragmented Shoot Apex of Grapevine

Abstract

Apical fragments of gravevine shoots cultured in a liquid medium containing cytokinin each develop into leaf-like stsuctures which give rise to adventitious buds on transfer to solid medium. The origin of the leaf-like structures forming the first part of this procedure was examined. Microdissection of the shoot apex revealed that leaf primordial pieces regenerated into leaf-like structures in droplet culture. These leaves were regenerated directly from primordial cells without the need for dedifferentiation and callus formation. The implications of these results are discussed in relation to studies on leaf determination.