Basana Gouda S¹*, Nirmala KS², C Suneetha³, Nagesha N⁴ and P Venkatesha Murthy²

¹Ph.D. Scholar, Department of Horticulture, College of Agriculture, University of Agricultural Sciences, G.K.V. K, Bengaluru, Karnataka – 560065, India
²Professor, Department of Horticulture, College of Agriculture, University of Agricultural Sciences, G.K.V.K, Bengaluru, Karnataka – 560065, India
³Associate Professor, Department of Horticulture, College of Agriculture, University of Agricultural Sciences, G.K.V.K, Bengaluru, Karnataka – 560065, India
⁴Professor, Department of Plant Biotechnology, College of Agriculture, University of Agricultural Sciences, G. K.V.K, Bengaluru, Karnataka – 560065, India

*Corresponding Author: Basana Gouda S, Ph.D. Scholar, Department of Horticulture, College of Agriculture, University of Agricultural Sciences, G.K.V. K, Bengaluru, Karnataka – 560065, India.

Received: December 04, 2025; Published: December 11, 2025

Abstract

Eulophia nuda Lindl. is a medicinally important terrestrial orchid facing rapid population decline due to overharvesting, habitat degradation, and inherently poor natural regeneration, underscoring the need for efficient propagation strategies. This study developed an optimized and reproducible protocol for in vitro root induction and ex vitro acclimatization of E. nuda plantlets. Regenerated shoots were cultured on half-strength Orchimax medium containing different concentrations of indole-3-butyric acid (IBA) to identify the most effective auxin regime for rooting. Among all treatments, 2.0 mg/L IBA proved optimal, promoting the earliest root initiation (11.10 days), the highest number of roots (4.59), and the greatest root length (4.12 cm) at 90 days after culturing in rooting media. Rooted plantlets were subsequently subjected to a two-stage acclimatization process, wherein primary hardening in sterile cocopeat achieved survival rates exceeding 95%. During secondary hardening, three substrate mixtures were evaluated, and the combination of red soil, sand, cocopeat, and vermicompost (2:1:1:1) resulted in the highest survival rates (86% at 30 days and 83% at 60 days). The integrated rooting and hardening system established in this study significantly enhances plantlet vigour and ex vitro establishment, offering a reliable and scalable protocol for large-scale propagation, conservation, and potential reintroduction of this economically and therapeutically valuable orchid species.

Keywords: Acclimatization; Conservation; Hardening; In vitro Rooting; Orchimax Medium

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Citation

Citation: Basana Gouda S., et al. “In vitro Root Induction and Ex vitro Acclimatization of the Endangered Orchid Eulophia nuda Lindl. for Conservation and Large-Scale Propagation". Acta Scientific Agriculture 9.12 (2025): 29-36.

Copyright

Copyright: © 2025 Basana Gouda S., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.