Cryopreservation of Orchid Seeds, Protocorms, and Pollen

Abstract

The popularity of orchids has a worldwide reach, placing them as the top cut flower and potted plant in the international market. Last year, the United States Department of Agriculture upgraded orchids ranking first as flowering potted plant in the United States with wholesale value estimates of about $200 million. Orchids are indicator plants to the health of a habitat. Over collection and habitat destruction have promoted the reduction in wild orchid natural populations. Therefore, conservation of orchids needs immediate attention. Cryopreservation is an efficient technique for long-term storage of orchid plant material and can assist in the preservation of endangered orchids. Furthermore, it offers an alternative for long-term storage of orchid genetic material for breeding and genetic improvement programs. In this paper we summarize several studies with cryopreservation of orchid material, which have been developed in our laboratory over the past seven years at the University of Florida’s Tropical Research Center. We have developed an efficient protocol for cryopreservation of hybrid mature seeds, protocorms, and pollen of Dendrobium Sw. species and hybrids. Improved cryopreservation protocols were developed using phloroglucinol as a cryoprotectant. Seedlings from cryopreserved Oncidium flexuosum Lodd. seeds were also assessed for genetic stability after cryopreservation.