Asymbiotic seed germination, in vitro seedling development, and greenhouse acclimatization of the threatened terrestrial orchid Bletia purpurea

• Published in: Plant cell, tissue and organ culture tissue and organ culture, 2008-07, Vol.94 (1), p.11-21
• Main Authors: Dutra, Daniela, Johnson, Timothy R, Kauth, Philip J, Stewart, Scott L, Kane, Michael E, Richardson, Larry
• Format: Article
• Language: English
• Subjects: acclimation; asymbiotic seed germination; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Bletia purpurea; corms; culture media; dry matter accumulation; Eukaryotic cell cultures; Fundamental and applied biological sciences. Psychology; greenhouse production; growing media; in vitro studies; leaves; Life Sciences; Methods. Procedures. Technologies; Miscellaneous; mortality; Orchidaceae; Original Paper; photoperiod; Plant cells and fungal cells; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant Sciences; roots; seed germination; seedling growth; shoots; soilless media; symbiosis; threatened species; wild plants
• ISSN: 0167-6857; 1573-5044
• DOI: 10.1007/s11240-008-9382-0

Procedures for asymbiotic seed germination and seedling acclimatization were developed for Bletia purpurea, a threatened North America native terrestrial orchid. Six asymbiotic orchid seed germination media (Knudson C, PhytoTechnology Orchid Seed Sowing Medium, Malmgren Modified Terrestrial Orchid Medium, Vacin & Went Modified Orchid Medium, [fraction one-half]-strengh Murashige & Skoog, and BM-1 Terrestrial Orchid Medium) were examined for their effectiveness in promoting seed germination and protocorm development of B. purpurea in either a 0/24 h or 16/8 h L/D photoperiod. Germination occurred regardless of medium or photoperiod treatment. However, advanced seedling development (Stage 6) only occurred on Vacin & Went Modified Orchid Medium in the 16/8 h L/D photoperiod. Further effects of photoperiod on in vitro seedling development were also examined. Shoot length, leaf width, root number and length, and fresh weight and dry weight in the 16/8 h L/D photoperiod were all significantly different when compared to the 8/16 h and 12/12 L/D photoperiods. In vitro seedlings were readily acclimatized to greenhouse conditions. Seedlings showed high survival all potting media. Seedlings acclimatized in Fafard Mix 4 potting medium developed significantly longer roots. Corm formation occurred regardless of potting media used.