Gh. Esmaeili - Department of Horticultural Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Islamic Republic of Iran.
M. Azizi - Department of Horticultural Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Islamic Republic of Iran.
H. Arouiee - Department of Horticultural Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Islamic Republic of Iran.
L. Samiei - Research Center of Plant Science, Ferdowsi University of Mashhad, Mashhad, Islamic Republic of Iran.

The aim of this study was to investigate the in vitro proliferation of Astragalus adscendens. Explants were taken from hypocotyl and cotyledon and were cultured on the basic medium of Murashige and Skoog (MS) complemented with various plant growth regulators, (NAA, BAP, KIN, ZEA), to induce direct shoot regeneration. Callus induction was significantly affected by different concentrations of PGRs. Callus formation was observed from hypocotyl explants, but they were not induced to adventitious shoot regeneration and most of them were turned into brown. Therefore, rapid multiplication, performed using shoot apical buds, and obtained from ۱۵-day old sterile seedlings. Apical buds were cultured on MS medium containing various levels of BAP, KIN and ZEA (۰.۵, ۱.۰, ۲.۰ and ۴.۰ mg L-۱) alone or in combination with ۰.۵ mg L-۱ NAA. The highest number of shoot regenerants (۸.۵/explants) and leaves (۲۲.۴/explants) obtained on MS medium with ۴ mg L-۱ BAP. The highest root induction (۱۰۰%) was obtained from MS media supplemented with ۰.۳ mg L-۱ NAA. Rooted plantlets were successfully acclimatized in pots with ۱:۱:۱ mixture of soil, peat, and perlite.

Apical buds, Callus induction, Clonal propagation, Gavan-e-Gaz-angabin, Proliferation