In vitro ORCHID SEEDLINGS (Laelia purpurata Lindl var venosa X Cattleya warneri T. Moore alba) GROWTH UNDER DIFFERENT CONCENTRATIONS OF SACCHAROSE AND FRUCTOSE

Current study aimed to evaluate the development of hybrid orchid seedlings of Laelia purpurata Lindl var venosa X Cattleya warneri T. Moore alba in Knudson "C" culture medium. Different concentrations of sucrose and fructose (10, 15, 20 and 25 g/L) were added to culture medium. Following criteria were assessed 180 days after seedlings transferences to different culture medium: number of leaves, number of buddings and roots, root size average (root’s length/diameter), seedlings length and, fresh and dry biomass. Data were submitted to variance analysis and averages were compared by Scott-Knott’s test with a significance of 5%. Reduction of evaluated characteristics was observed when fructose’s concentration was increased. Knudson traditional "C" medium (20 g/L sucrose) has improved results in hybrid Laelia purpurata var venous X Cattleya warneri alba growth. Superior development was observed in 10 g/L and 15 g/L Fructose’s concentrations.