Shoot apical meristems were used to establish regenerative axillary bud cultures of 9 muscadine grape cultivars. Meristems taken from 10 cm long shoots had less contamination (3%) and a higher survival rate (94%) than those from shorter or longer shoots. Of media tested, MS, 1/2 MS, and CzD resulted in equivalent shoot proliferation rates, whereas, WPM produced stunted shoots. When pooling results for 3 cultivars, 5, 10 and 20/~M BA and 5/~M TDZ produced the highest average number of shoots per cultured apex (3.4-3.8). However, shoots produced with TDZ were stunted and did not root well. For rooting of shoots directly in potting mix, a rooting powder pretreatment significantly increased the number of roots per shoot but did not affect percent rooting or root length. For rooting in vitro, 1/~M NAA significantly increased all parameters measured. Although more shoots rooted in vitro than in vivo (77% vs. 46%), the latter was judged preferable since acclimatized plants were produced in less time and a major culture step was eliminated. Significant differences among cultivars were noted for measured responses in all experiments.

Ovules of seedless bunch grapes (Vitis spp.) fertilized by controlled pollination increased in size during berry development. More ovules cultured 10 days or 60 to 70 days after pollination became brown compared to those cultured at 20 to 40 days. Cultured ovules developed with and without endosperm. Globular to torpedo stage embryos were recovered. More embryos and plants were recovered from ovules cultured at 40 or 60 days than at 10 or 20 days after pollination. Pollen parent significantly affected both embryo and plant recovery at certain sampling times. BA incorporated into medium significantly increased embryo germination percentage. Electrophoretic analysis of glucosephosphate isomerase in progeny showed that 67% to 88% were hybrids of controlled crosses. Of four vines that fruited thus far, two were seedless. Seedless progeny had smaller seed traces than either parent. Chemical name used: N-(phenylmethyl) -1H-purin-6-amine (BA).

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