Effect of Gibberellic Acid on Sprouting of Arrowroot (Colocasia esculenta L.) Rhizomes in Different Media

Abstract

Arrowroot [Colocasia esculenta (L.) Schott] is traditionally propagated through headsets or suckers. However, initiating an arrowroot crop remains a challenge due to shortages of propagation materials. This study investigated the potential of nodal cuttings derived from rhizomes produced by arrowroot corms to develop into plantlets suitable for propagation. Potted arrowroot mother plants were treated with varying concentrations of gibberellic acid (GA3): 100, 250, 500, and 750 parts per million (ppm), leading to the development of corm-rhizomes. A pot experiment was conducted using a split-plot design nested within a completely randomized design (CRD) framework, with four replications to ensure statistical rigor. The sprouting media constituted the main plot, while the application of GA3 (gibberellic acid) was assigned to the sub-plots. The resulting rhizomes from the GA3 treatment were sliced into two-node cuttings and sown in either river sand or sawdust-filled pots. The pots were then placed in controlled sprouting chamber with ideal temperature and humidity conditions. The highest sprouting percentage of 96% was recorded for nodal cuttings propagated in river sand and treated with 500 ppm GA3, 250 ppm (81%), 750 ppm (79%), while 100 ppm yielded the lowest rate at 79%, with same GA3 concentrations in the sawdust demonstrating varying lower percentages. The interactions between GA3, Media and time were highly significant. Therefore, river sand emerged as the superior medium for initial growth. These findings underscore the potential of this propagation method, but further research into single-node cuttings and the evaluation of the resulting plantlets under field conditions is essential to evaluate the scalability and yield performance for arrowroot production.