Effect of Sucrose Concentrations and Incubation Periods on in Vitro Rooting of Moris Pineapple (Ananas comosus)

Abstract

The effect of 6 sucrose concentrations (5, 10, 15, 20, 25, 30 g/l) over 4 incubation periods (30, 45, 60, 75 days) on in vitro rooting of Moris pineapple cultured in liquid half strength MS medium enriched with IBA at 2.0 mg/l was investigated. At all incubation periods, all shoots in medium enriched with sucrose at 5 g/l failed to root, and no roots formed within the first 30 days in medium enriched with sucrose at 10 g/l. After 30 days of incubation, the highest rooting percentage (66 %), tallest plantlets (23 mm tall), highest (3.4 roots) and longest (5.3 mm) root per shoot were obtained in medium enriched with sucrose at 25, 10, 15, 15 g/l respectively, while after 45 days, the highest of all rooting aspects (75 %, 32.3 mm tall, 3.7 roots, 7 mm long), were obtained in medium enriched with sucrose at 15 g/l. After 60 days, the highest rooting percentage (91.7 %) and tallest plantlets (36.7 mm tall) were obtained in medium enriched with sucrose at 20 g/l while highest roots per shoot (3.7 roots) and longest root (10.7 mm) were obtained in medium enriched with sucrose at 15 g/l. After 75 days, all shoots rooted (100 %) in medium enriched with sucrose at 10 and 20 g/l, while sucrose at 25 g/l resulted in tallest plantlets (46.3 mm tall) and at 20 g/l resulted in highest (4.7 roots) and longest roots (27.3 mm). At each incubation period, there was a different optimum sucrose enrichment for different rooting parameters.