High frequency adventitious shoot regeneration from immature cotyledons of pea (Pisum sativum L.)

A procedure has been developed which allows high frequency adventitious shoot regeneration from immature cotyledons of pea. Prolific shoot regeneration occurred following an initial callus growth on a Murashige and Skoog (MS) medium containing 0.5 mg/l 6-benzylaminopurine (BAP) and 4 mg/l α-naphthaleneacetic acid (NAA). Cotyledon expiants proximal to the embryonic axis had the highest regeneration potential, however, the presence of an embryonic axis inhibited adventitious shoot regeneration. Addition of silver nitrate (AgNO3) to the medium did not promote the number of regenerated shoots but resulted in shoots with well developed tendrils and large stipules which had a reduced rooting capacity. Regenerated shoots rooted readily (80-90%) in half strength MS medium containing 1 mg/l indole-butyric acid (IBA) and further established well in compost.