In vitro regeneration from leaf explants of Petunia hybrida L

Abstract

The effect of different levels of 6-benzylaminopurine (BAP) and α-naphthylacetic acid (NAA) on direct adventitious shoot induction was evaluated. Explant regeneration frequency, number of shoots, and rooting frequency were evaluated. Leaf explants of ‘Ramblin Nu Blue’ manifested significantly (p < 0.01) highest mean explant regeneration frequency (75.2%) with a highest mean number of adventitious shoots (4.4). ‘Purple Velvet’ and ‘Ramblin Nu Blue’ showed the highest explant regeneration frequency on culture medium supplemented with 0.8 mg l-1 BAP and 0.1 mg l-1 NAA, while growth regulators combination 0.4 mg l-1 BAP and 0.1 mg l-1 NAA promoted the explant regeneration at highest frequency from leaf discs of ‘Touha’. Studies have shown that the formation of adventitious shoots from leaf discs of studied Petunia hybrida cultivars depends not only on the combination of growth regulators and their interaction with genotype, but also on the position of explants on the culture medium. Leaf discs of investigated cultivars placed with adaxial side on the medium showed significantly higher (p < 0.01) explant regeneration frequency in comparison with these placed with abaxial side. It was established that for root induction MS medium should be supplemented by 0.5 mg l-1 NAA for ‘Purple Velvet’, 0.1 mg l-1 NAA or 0.1 mg l-1 IAA for ‘Ramblin Nu Blue’, and 0.1 mg l-1 IAA for ‘Touha’.