Climate change may separate wild vanilla plants from pollinators, risking future supply

Vanilla aromas are widely used in food, pharmaceutical products and cosmetics. The main source, Vanilla Planningolia, is however vulnerable to diseases, drought and heat – stressors who should become more frequent under climate change. Species of wild vanilla offer a genetic reservoir of wild producers from parents ensuring the future of vanilla harvest. Scientists have now examined how climate change could cause discrepancies in the overlap of wild vanilla habitat and their pollinating insects.

“Climate Change May Lead to A Reduced Habitat Overlap Between Vanilla Orchid Species and Their Pollinators, Resulting in Plant-Pollinalator Decoupling That Negatively Affects The Survival of Wild Vanilla Populations,” Said Dr. Charlotte Watteyn, A Researcher at Ku Leuven and Lankester Botanical Garden Research Center at University of Costa Rica (UVR) and First Author of the Borders in plant science study.

“The conservation of natural populations of wild vanilla species and the enormous genetic diversity they hold is crucial to ensure the future of vanilla, a key tropical culture for the global food industry,” added the main author, Professor Bart Muys of Ku Leuven.

Incompatible habitats

The team modeled the distribution and overlapping of the habitat of 11 species of neotropical vanilla and seven pollinators previously observed in two climate change scenarios. The scenario “Middle of the Road” (SSP2.4-5) represents moderate challenges both at the attenuation and adaptation of climate change, and follows a balanced energy development path, while the “Rocky Road” scenario (SSP3-7.0) is characterized by many challenges, strongly connects on fossil combustibles, and there is less cooperation overall to the mititigation of climate change.

They found that for seven vanilla species, climatic conditions could become more favorable by 2050 in the two scenarios. These species could extend their habitats up to 140%, while the area with an appropriate habitat for the other four species should reduce up to 53%.

For pollinators, the future on a warming planet could be more disastrous. The habitat ability of all pollinators has proven to be decreasing, with a slightly higher negative change in the SSP3-7.0 scenario. “Despite the possible increase in habitat appropriate for certain species of vanilla, their dependence on pollinators can jeopardize the survival of natural populations,” said Watteyn.

It is not clear if other pollinators can replace those who could disappear from wild vanilla habitats. “Vanilla species are known for their specialized relationships with pollinators, therefore, they may have difficulty replacing pollinators,” said Watteyn. “The future may seem brighter for species that do not depend on a single pollination vector.”

Most species, however, generally depend on one or a few pollinators.

Robust cultures required

Maintaining wild vanilla plants is not only important for biodiversity but also for agriculture. The species of cultures used in trade are characterized by a low genetic diversity, which can negatively affect the yield, quality and stability of products, but agricultural resilience could be improved by the diversification of crops.

“Wild vanilla species have the potential to mitigate these problems while they continue to co-evolve in nature, in development of interest traits for the improvement of crops, for example, drought and heat tolerance and resistance to pathogens,” said Muys.

Many vanilla species are already threatened and natural pollination rarely occurs. Forest fragmentation, loss of habitat and extreme temperatures exacerbate an already disastrous scenario for the survival of the “queen of all flavors”.

“Collaborative research on the ecology and genetic diversity of wild vanilla through its natural distribution is essential if we want to take vanilla breeding in the future, using ethics and sustainably the local variation to meet global needs,” said the co-author of Professor Adam Karremans, director of the Lankester Botanical Research Center.

The results, have warned the authors, should be interpreted carefully as occurrence of occurrence for wild vanilla species and pollinators are rare. Habitat overlaps could move when ecological interactions such as the dispersion of seeds and interactions with microorganisms, or disturbances such as conversion of housing and illegal extraction are also included in the models.

“Like cocoa and coffee, vanilla is a world export culture with high international market value.” Culture benefits small agricultural communities through the tropics, there is therefore an urgent need to improve the resilience of vanilla systems. “