EFFECTS OF SUBSTRATES AND PLANT GROWTH REGULATORS ON THE ROOTING PERFORMANCE OF UBI (Dioscorea alata L.) SETTS

Abstract

This study assessed the rooting performance and initial growth response of Ubi (Dioscorea alata L.) setts subjected to different rooting substrates and plant growth regulators (PGRs) under nursery condition.  A Completely Randomized Design (CRD) with three replications was conducted to test the most effective substrates (Factor A) and plant growth regulators PGRs (Factor B) Parameters were measured including days to root emergence, rooting success, root length, and survival percentage were analyzed using Analysis of Variance (ANOVA) and the Least Significant Difference (LSD) test. The Substrates were used are loam soil, pre decomposed rice hull, and cocopeat while in plant growth regulators applied were Distilled Water as negative control, Alpha Naphthalene Acetic Acid (ANAA), Aloe Vera Leaf extract, Banana Peel Extract and Green Coconut Water. Results revealed that there was no significant effect on root emergence during the first seven days among substrates but in plant growth regulators, Banana Peel Extract (BPE) significantly aided in breaking the tuber epidermis at the early growth of ubi setts. At the 30 days after planting there were significant differences emerged across all parameters. The Cocopeat substrates proved to be the most effective among treatment, providing optimal moisture retention and low mechanical resistance for root elongation. Among the PGRs, Green Coconut Water significantly performed compared to other treatments in increasing the average number of roots and total rooting success. Furthermore, the combination of cocopeat and green coconut water (S₃P₅) maximized the percent survival of setts. Based on economic perspective, using of green coconut water is recommended as cheap and locally available alternative to synthetic hormones, offering a high return on investment for small scale growers by producing high quality planting materials.