Evaluation of aloe vera gel as a commercial auxin replacement for in-vitro rooting of sour banana (Musa acuminata)

Abstract

In vitro propagation is a controlled, sterile method for growing and multiplying plant cells, tissues or organs using Murashige and Skoog (MS) medium, supplemented with growth regulators such as auxins. Indole-3-acetic acid (IAA), a synthetic auxin is widely used to promote in- vitro rooting in various plant species, including sour banana (Musa acuminata). However, concerns regarding the potential phytotoxicity and environmental impact of synthetic growth regulators have increased interest in natural, plant-based alternatives. This study investigates the potential of aloe vera (Aloe barbadensis Miller) gel as a natural substitute for commercial auxin in the in vitro rooting of sour banana. Aloe vera gel (AvG), known for its richness in bioactive compounds, including vitamins, enzymes, and phytohormones was incorporated into MS rooting medium at varying concentrations (120, 160, 200, 240, 280, 360, 440 and 520 g/L AvG). The experiment evaluated several parameters, including days to root initiation, number of roots, root length, plant growth rate, plant height, root dry weight and plant dry weight, compared to standard treatments with IAA. The study was conducted using a Completely Randomized Design (CRD) with 9 treatments, each replicated 15 times. Results revealed that supplementing the medium with AvG had a significant effect on growth parameters. The highest number of roots (7) and the shortest time to root formation (4 days) were recorded with 440 g/L AvG in full-strength MS medium. Increased AvG concentrations generally improved rooting ability. Notably, the 160 g/L AvG treatment was most effective in promoting root length (56.9 mm) and plant growth rate (6.8). The highest plant height (52.3) was observed with 280 g/L AvG in full- strength MS medium. Root dry weight (0.05g) was recorded with 0.1 mg/L IAA in full-strength MS medium, while plant dry weight (0.1g) was noted with 120 g/L AvG in full-strength MS medium. These findings suggest that aloe vera gel can be used as a viable natural alternative to synthetic auxin for in vitro rooting media used in growing sour bananas, improving multiple growth parameters.