PRODUCTION OF TRIPLOID GRAPES BY IN OVULO EMBRYO CULTURE

Triploid grapes were produced by in ovulo embryo culture. Ovules were obtained from 5 crosses: Rosario Bianco (V. vinifera L. 2x) x Kyoho (V . vinifera x V. labrusca L. 4x), Katta Kourgan(V. vinifera L. 2x)x Kyo ho, Kyoho x Rosario Bianco, Kyoho x Sekirei (V. vinifera L. 2x) and Ky oho x Rizamat (V. vinifera L. 2x). Most embryos were obtained from ovu les cultured at veraison. The addition of indole-3-acetic acid (2.0 mg .l(-1)) and gibberellic acid (0.4 mg.l(-1)) to 1/2 MS (half strength m acro-elements) medium promoted the formation and growth of embryos. Al though only a few embryos germinated directly from ruptured ovules, em bryos excised from cultured ovules germinated successfully by in vitro culture. This paper demonstrates that in ovulo embryo culture is expe cted to be an efficient method to produce triploid grapes.