Medium composition, developmental temperature, and pollen density enhanced in vitro pollen germination in Phalaenopsis
Journal
Scientia Horticulturae
Journal Volume
366
ISSN
0304-4238
Date Issued
2026-08
Author(s)
Abstract
In vitro pollen germination is a fundamental tool for assessing the viability of the parental lines in breeding. The conditions for in vitro germination require consistent improvement to ensure correlation with actual in vivo germination performance. However, research on the in vitro germination of Phalaenopsis pollen remains limited. This study investigated the effects of modifying the germination media, pollinia developmental temperature, and pollen population size on pollen germination. Compared with the standard Brewbaker and Kwack (BK) medium containing 100 mg·L⁻¹ H3BO3 and 300 mg·L⁻¹ Ca(NO3)2·4H2O, the modified BK medium supplemented with 125 mg·L⁻¹ H3BO3 and 100 mg·L⁻¹ Ca(NO3)2·4H2O significantly enhanced pollen germination, increasing rates from 29.4% to 51.8% in Phalaenopsis Hualien Pink Apple ‘Hualien No 1-Pink Apple’ and from 16.8% to 26.4% in Phalaenopsis Sogo Yukidian ‘V3’. Furthermore, extending the cooling period until pollinia development is critical for achieving high pollen viability. An extended period of cooler developmental temperature (21/17 °C day/night from 94 to 121 days) enhanced pollen viability, with germination rates improving by 45.4% and pollen tube length increasing. Notably, this study demonstrates a pollen population effect in Phalaenopsis Hualien Pink Apple ‘Hualien No 1-Pink Apple’, where increased pollen density promotes both germination and tube growth. These findings provide essential guidance for Phalaenopsis breeding programs, offering a potential framework to improve cross-pollination efficiency and reproductive success in commercial orchid production. © 2026 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC license. http://creativecommons.org/licenses/by-nc/4.0/
Subjects
Boron
Calcium
Modified BK medium
Orchid breeding
Pollen population effect
Pollen viability
Publisher
Elsevier BV
Description
Article number 115073
Type
journal article