Improvement of shoot proliferation in the micropropagation of mulberry {Moms alba L.)

Abstract

Leaves of mulberry tree (Morus alba L.) are the only source of food for the silkworms (Bombyx mori L.). As the vegetative propagation of mulberry is strictly restricted to a single season (September-October) in Bangladesh, adequate production of leaves for silkworm rearing is interrupted every year. Efforts were made to search for an efficient protocol for year round mulberry propagation through in vitro techniques by single node culture. Among the media tested, Murashige and Skoog ( MS) medium was found to be best followed by Woody Plant (WP) medium. Highest percentage (93.2%) of shoot proliferation was achieved in MS+5.0 pM benzyladenine (BA). Synergistic action of BA and kinetin (5.0 pM each) produced good number (15.3) of microshoots per culture. Addition of tyrosine (100 mg l 1) coupled with synergistic action of cytokinins increased the number of microshoots (40.7%) remarkably. Best rooting was achieved in low concentration (1.0 pM) of indolebutyric acid (IBA) alone. In vitro derived plantlets were acclimatized conveniently and 85-90% survival of plants was observed without any abnormalities in soil.