Adenosine monophosphate enhances callus regeneration competence for de novo plant organogenesis

Dear Editor,Plant tissue culture involves callus formation and de novo shoot regeneration.First,explants from differentiated tissues are used to generate a pluripotent cell mass,called callus,on auxin-rich callus-inducing medium(CIM),followed by shoot regeneration on cytokinin-rich shoot-inducing medium(SiM).Callus results from division of pericycle-like cells(Atta et al.,2009;Sugimoto et al.,2010);its cellular identity resembles that of lateral root primordia(Atta et al.,2009;Sugimoto et al.,2010).Callus acquires cellular pluripotency by forming root stem cell niches on CIM(Sugimoto et al.,2010)。