Callus production and somatic embryogenesis from white ash

Nonstratified white ash (Fraxinus americana L.) seeds, with one-third or one-half of their length excised, germinated 100% in vitro compared to 0% for noncut seeds on Driver and Kuniyuki walnut (DKW) medium with no plant growth regulators. Explants, therefore, consisted of one-third or one-half of the seeds containing the embryonic axis with portions of the cotyledons. More callus formed on the cut end of the cotyledons on media with 1 μM than 10 μM 2,4-D. More callus and somatic embryos formed on seedlings that remained on primary medium for 4 weeks with 5 μM BA and 2,4-D than when BA was not present