Asymbiotic Seed Germination and In Vitro Propagation of the Thai Rare Orchid Species; <i>Eulophia bicallosa</i> (D.Don) P.F.Hunt & Summerh.

An efficient in vitro propagation protocol for <i>Eulophia bicallosa</i> was developed using asymbiotic seed germination and protocorm proliferation. The effect of light on seed germination and development was evaluated on Vacin and Went (VW) medium under five conditions: darkness, white...

Full description

Saved in:
Bibliographic Details
Main Authors: Thanakorn Wongsa, Jittra Piapukiew, Kanlaya Kuenkaew, Chatchaya Somsanook, Onrut Sapatee, Julaluk Linjikao, Boworn Kunakhonnuruk, Anupan Kongbangkerd
Format: Article
Language:English
Published: MDPI AG 2025-07-01
Series:Plants
Subjects:
Online Access:https://www.mdpi.com/2223-7747/14/14/2212
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:An efficient in vitro propagation protocol for <i>Eulophia bicallosa</i> was developed using asymbiotic seed germination and protocorm proliferation. The effect of light on seed germination and development was evaluated on Vacin and Went (VW) medium under five conditions: darkness, white, green, red, and blue light for 24 weeks. Blue and red light significantly accelerated seed development, allowing progression to stage 5 within 24 weeks. For protocorm proliferation, six semi-solid culture media were tested. Half-strength Murashige and Skoog (½MS) medium yielded the best results after 8 weeks, producing the highest numbers of shoots (1.0), leaves (1.1), and roots (4.2) per protocorm, with 100% survival. The effects of organic additives were also evaluated using coconut water and potato extract. A combination of 200 mL L<sup>−1</sup> coconut water and 50 g L<sup>−1</sup> potato extract enhanced shoot formation (1.7 shoots), while 150 mL L<sup>−1</sup> coconut water with 50 g L<sup>−1</sup> potato extract increased both leaf (1.9) and root (8.8) numbers. The effects of cytokinins (benzyladenine (BA), kinetin (6-furfurylaminopurine), and thidiazuron (TDZ)) and auxins (indole-3-acetic acid (IAA), α-naphthalene acetic acid (NAA), indole-3-butyric acid (IBA), and 2,4-dichlorophenoxyacetic acid (2,4-D)) were investigated using ½MS medium supplemented with each plant growth regulator individually at concentrations of 0, 0.1, 0.5, 1.0, and 2.0 mg L<sup>−1</sup>. Among the cytokinins, 0.1 mg L<sup>−1</sup> BA produced the highest survival rate (96%), while 1.0 mg L<sup>−1</sup> BA induced the greatest shoot formation (93%, 2.3 shoots). Among the auxins, 0.1 mg L<sup>−1</sup> IAA resulted in the highest survival (96%), and 1.0 mg L<sup>−1</sup> IAA significantly enhanced root induction (4.2 roots per protocorm). Acclimatization in pots containing a 1:1:1 (<i>v</i>/<i>v</i>) mixture of pumice, sand, and soil resulted in 100% survival. This protocol provides a reliable and effective approach for the mass propagation and ex situ conservation of <i>E</i>. <i>bicallosa</i>.
ISSN:2223-7747