Effect of growth regulators on indirect organogenesis of two grapevines (Vitis vinifera L.) cultivars

Abstract

Establishment of efficient protocol for high-frequency of indirect regeneration of plantlets has a vital role in the analysis of genetic material in mass propagated plants. The optimal levels of growth regulators and light conditions were investigated on callus induction and organogenesis of cultured grapevine from in vitro tissues. Maximum calluses and shoots were produced by using medium supplemented with four different growth regulators as alone or in combinations. An observation of maximum calluses (51%) were recorded when 0.5 mg/l thidiazuron (TDZ), was combined with 0.5 mg/l indole-3-butyric acid (IBA) for Chenin blanc cv. Produced calluses were observed with different size and nearly similar colors. In this experiment, shoot initiation was observed in dark condition. The light condition did not induce the shoot on the same dark treatment. Different concentrations of 6-benzylaminopurine (BAP) and TDZ tested alone were not induced at any shoots from callus, but re-callusing the explant. Thus, shoot induction was observed when different concentration of BAP and TDZ were combined with auxins. The calluses produced from leaf did not produce high percentages of shoots. Further studies are needed to optimize the maximum percentage of somatic embryogenesis.   Key words: Callus, growth regulators, organogenesis, grapevine, dark.