Growth Regulator and Axillary Bud Position Effects on in Vitro Establishment of Vitis rotundifolia

Abstract

Four muscadine grape (Vitis rotundifolia Michx.) cultivars (Carlos, Noble, Regale, and Tarheel) were evaluated for their ability to be cultured in vitro. Axillary buds were placed on Murashige and Skoog medium as modified by Chee. Different levels of benzylaminopurine [(BA) 0.5 to 10.0 μ m ], kinetin [(KIN) 0.5 to 5.0 μ m ], and thidiazuron [(TDZ) 0.5 to 11.3 μ m ], and different explant positions were evaluated for their effect on in vitro explant establishment and shoot production. Thidiazuron (2.3 to 4.5 μ m ) alone or in combination with BA (1.0 to 5.0 μ m ) or KIN (1.0 or 5.0 μ m ) was effective for establishing axillary buds. Similar levels were also effective for promoting shoot proliferation. Explants originating from the 10 basal nodes of a shoot with at least 25 nodes gave better shoot proliferation than explants originating from the 10 distal nodes. Chemical names used: 6-benzylaminopurine, 6-furfurylaminopu. rine (kinetin):N -phenyl- N'- l,2,3 -thiadiazol-5-y lurea (thidiazuron).