Meios de cultivo e sacarose no crescimento inicial in vitro de Miltonia flavescens

Abstract

The in vitro culture has been widely used for the ornamental plants propagation. The choice of the best medium and organic products concentration, such as sucrose, are decisive in the protocols. Thus, the aim of this study was to evaluate the initial growth of Miltonia flavescens, grown for 90 and 180 days, in four culture media supplemented with different concentrations of sucrose. Plants aged 12 months were germinated in vitro and cultured on MS, MS ½ K and VW media each one supplemented with 1.5g L-1 of activated charcoal, 6.5g L-1 bacteriological agar and 25, 30 35, 40 and 45g L-1 sucrose. After 90 and 180 days, fresh mass, number of roots, leaves and shoots, length shoot and the largest root were evaluated. The highest average for number of roots, shoot, length and total fresh weight were obtained in plants grown for 180 days on MS ½ medium supplemented with 25g L-1 sucrose. The greater length of roots was observed in plants grown for 180 days on MS medium supplemented with 45g L-1 sucrose. M. flavescens showed higher growth of shoots and roots when cultivated for 180 days on MS ½ medium supplemented with 25g L-1 sucrose.