In vitro propagation of Aegle marmelos (L.) Corrêa via nodal cultures: effects of auxin–cytokinin combinations and acclimatization substrates

Aegle marmelos (L.) Corrêa is an important medicinal and fruit tree with increasing demand for uniform planting material. This study aimed to optimize an in vitro propagation protocol using nodal explants by evaluating auxin–cytokinin combinations for shoot induction, auxin treatments for rooting, and substrate compositions for acclimatization. On Murashige and Skoog (MS) medium, 1.5 mg L⁻¹ BAP combined with 0.5 mg L⁻¹ IBA produced the highest shoot proliferation (4.90 shoots per explant after 8 weeks), significantly outperforming the hormone-free control. Rooting was most effective on MS medium supplemented with 1.0 mg L⁻¹ α-NAA and 1.5 mg L⁻¹ IBA, yielding the highest root number (3.23) and root length (1.49 cm). During acclimatization, plantlets grown on a rice husk: coconut fiber: loam substrate (1:2:2) showed 100% survival and vigorous growth. The protocol provides reproducible experimental data supporting efficient micropropagation and ex situ conservation of A. marmelos.