Intersubgeneric Hybridization between Muscadinia and Euvitis Species

Abstract

The genus Vitis contains two subgenera: Euvitis Planch. (with the common name bunch grapes) and Muscadinia Planch. (with the common name muscadine grapes). The muscadine grapes (V. rotundifolia) are originated and limited to the southeastern United States and are distinguished from the Euvitis species morphologically and cytologically. They are characterized by high disease and pest resistance, and unique muscat flavor. Bunch grapes, with a total of 60-plus species, are grown world-wide and can be grouped into the American species, the Asiatic species and the European grape (V. vinifera) according to their geographical origination. V. vinifera, which is known for good fruit quality, is the predominant commercial species. Attempts to produce rotundifolia–vinifera hybrids to combine good fruit quality and disease resistance of both into F1 hybrids have been made by grape breeders for many years. Limited success was only reported when the V. vinifera was used as seed parents and it failed vice versa. This study extended the crosses between the V. rotundifolia and other Euvitis species originated from North America and East Asia to see if hybrids could be produced from any of these crosses. Results indicated that a limited success were achieved in a few crosses [muscadine (female) × Euvitis species] while failure occurred in most others. These hybrids may be used as bridges to carry the viticulturally important genes over to the muscadine grapes from V. vinifera. Microscopic study also revealed that the difficulty of hybridization between Muscadinia × Euvitis is due to the pre-fertilization barriers.