In Vitro Culture of Immature Embryo Obtained by Crossing between Tetraploid Grape 'Fujiminori' and Triploid 'Summer Black'

For the germination and differentiation of immature embryos obtained by artificial crossing between tetraploid grape 'Fujiminori' (Vitis vinifera x V. labruscana) and triploid 'Summer Black' (V. labruscana x V. vinifera), were incubated in vitro using MS medium supplemented with GA(3) or coconut water (CW) at various concentrations. The percentage of embryo formation of 'Fujiminori' x 'Summer Black' was 64.3%. Embryo germination percentage was higher than 95% in all the GA(3) treatments at the concentrations of 0.01, 0.05, 0.25, and 1.25 mg.L-1. However, only 15.8-31.6% of the germinated embryos successfully developed into normal plantlets. At higher concentration of GA(3), the plantlets developed infirm hypocotyls with over elongated and less enlarged structure. Among the treatments of CW at the concentrations of 5, 10, 15, and 20% (v/v), 10% and 15% were more effective and plantlet achievement percentage were 68.4 and 66.7%, respectively. The addition of 10% CW was most effective to obtain plantlets with optimal shoot length, node and root numbers. 15% CW was suitable to obtain plantlets with longer roots. Accordingly, the embryo culture using the MS medium supplemented with 10-15% CW was observed to be more efficient for germinating and growing the immature embryos produced from artificial crossing between tetraploid grape 'Fujiminori' and triploid 'Summer Black'.