A new parental pool for edible orchids

In this study, a total of 203 orchid species were identified from literature of which the tubers, or other parts, such as pseudobulbs, are consumed all over the world. Examples include Lizard orchids (Himantoglossum comperianum) of which the tubers are harvested from the wild to produce hot beverages and ice cream, called ‘salep’, in Mediterranean countries. Cross-compatibility of these edible orchid species was checked by compiling a matrix of known artificially created hybrids in The International Orchid Register. Thousands of artificial orchid hybrids have been registered here, but mostly for ornamental purposes.

Predicting the success of a new cross 

The genetic distance between species is known to predict viability of crosses. When genetic distances among species increase, the chances of creating a viable hybrid among these species become smaller. DNA sequences of edible orchid species were compiled from web-based databases and used to calculate pairwise phylogenetic distances. With the help of registered intergeneric hybrids, a heatmap analysis was carried out to visualize the potential of creating viable new crosses. The warmer the color, the higher the chances of creating a successful cross.

Creating a new artificial edible orchid hybrid

New hybrid crossings were attempted with help of horticultural orchid hobbyist growers from the Dutch Vereniging Orchideeën Vermeedering (VOV). Orchid genera and species were selected for crosses for which the heatmap analyses predicted high success rates. Parents of the putative hybrids were chosen based on desirable traits, such as fragrant tubers. This resulted in a successful cross of Dactylorhiza x foliorella with D. maculata subsp. fuchsii, combining a species with fragrant tubers with a hybrid containing the germplasm of an endemic species not currently traded as edible orchid. The newly created hybrid was registered with the International Orchid Register. 

Creating horticultural hybrids to save endangered orchid species in the wild

Artificially created plant hybrids have previously been shown to help conserve endangered species in the wild and create more sustainable trade. This study is the first to show that such an approach could also be applied to edible orchids. To overcome the higher costs of growing edible orchids rather than collecting them from the wild, tissue cultivation could reduce the costs of purchasing juvenile plants for further propagation by small enterprises, to return benefits to local communities.

More information

• Curious about further details of this study? Read the full publication in the journal Frontiers in Sustainable Food Systems.

Text: Susanne Masters and Barbara Gravendeel, Hortus botanicus Leiden
Images: Rogier van Vugt, Hortus botanicus Leiden (lead photo: Lizard orchid (Himantoglossum comperianum) harvested for edible tuber in the wild, in Turkey)