EFFECT OF LIQUID CULTURE ON THE GROWTH AND DEVELOPMENT OF MINIATURE ROSE (ROSA-CHINENSIS JACQ MINIMA)

The growth of miniature rose (Rosa chinensis Jacq. 'Minima') shoots cultured on liquid medium was greater relative to those cultured on two-phase (solid + liquid) medium or solid medium alone. Shoot multiplication ratio (number of multiple shoots per explant per subculture) on liquid medium was higher with 17.8-26.6 muM 6-benzyladenine at compared to that at 0-8.9 muM. Shoots grown on 30 ml or more of liquid medium had a higher multiplication ratio than those grown on 10 or 20 ml. The growth and multiplication ratio increased when the culture period was extended from 3 to 6 weeks, although plantlets began to exhibit some chlorosis by the 6th week. These conditions were maintained over four subcultures for cultivars 'Baby Katie', 'Lavender Jewel', 'Red Sunblaze' and 'Royal Sunblaze', with no significant change in multiplication ratio over time.