Understanding mycorrhizal fungi to propagate Australia’s imperilled leek orchids

Date: 22, Oct, 2021
Author(s): Marc Freestone   Noushka Reiter  
Publisher: TSR Hub

Leek-orchids (Prasophyllum) are at risk of extinction with 38 species currently listed as nationally threatened.  Many Critically Endangered species now remain only as a handful of plants from a single population, so habitat protection alone will not be sufficient to prevent their extinction. Despite ex-situ propagation being highlighted as a high priority for leek-orchid conservation and recovery, no previous breeding programs have been successful. We identified 26 species of mycorrhizal fungi growing in the roots of leek-orchids, most of which were new to science. Many were continentally widespread; some appeared to be habitat specialists. Some leek-orchids used just one species of fungi to germinate their seed, while others utilized up to six. We achieved repeatable germination of the Endangered Prasophyllum frenchii, and another 18 species of leek-orchid. Understanding orchid mycorrhizal fungi was an important step forward for leek-orchid propagation and conservation. These results will allow reintroduction programs for leek orchids to commence.