Biodiversity of plants of the Musa genus updated

Many species of the Musa genus are present in continental Southeast Asia, in the northern zone of its natural range of diversification. However, their distribution and intraspecific variability are still poorly understood. Collection missions in partnership with the MNHN and research institutes* in Vietnam, Laos and China made it possible to characterize morphologically and genetically more than 200 specimens belonging mainly to the species Musa balbisiana, M. itinerans, M. acuminata and M. yunnanensis. The scientific team coordinated by CIRAD in partnership with the Alliance of Bioversity International and CIAT thus confirms continental South-East Asia as the main center of diversification for the Musa genus.

A description of diversity on a scale never before equaled

“This is the first time that such diversity has been described between wild species of the genus Musabut also within each of these species. Until then, it was only very partially represented in major international ex situ collections”explains Christophe Jenny, geneticist at CIRAD and coordinator of the study.

For the geneticist, “it is urgent to be able to protect these species, which are now threatened, and preserve their potential exploitation as wild relatives of cultivated forms of banana trees”. Programs to safeguard this diversity have been put in place by the research teams in the countries surveyed.

Human impact on wildlife diversity

Although considered wild, the species studied are all affected to varying degrees by human exploitation.

Musa yunnanensis et M. acuminata subsp. Burmese are the most strictly wild forms and are harvested for livestock feed. They are rarely found outside their endemic areas.

M. itinerans is also not cultivated as such, but is actively collected in nature, leading over time to a form of selection, which has resulted in a geographically structured diversity.

The diversity of M. balbisianafor its part, is distributed on a very large scale and strongly structured geographically by human activities. This species whose fruits are eaten despite the presence of seeds, and whose vegetative parts are widely exploited, can be considered almost domesticated.

These different levels of human action on diversity and its organization, from simple opportunistic gathering to true domestication, make it possible to understand the successive stages ofevolutionary history of the banana tree. They allow us to better understand the diversity of cultivated banana varietiesbuilt among other things by the combined contribution of several of these species.

In the next part of the study, the scientific team will endeavor to describe and explain the diversity and originality of the cultivated forms observed during these collections.

* Institute of Tropical Biology, Northern Mountainous Agriculture and Forestry Science Institute (Vietnam) ; The Cabinet of the Lao Academy of Science and Technology, (Laos) ; Kunming Institute of Botany (Chine)

Reference

Jenny C, Sachter-Smith G, Breton C, Rivallan R, Jacquemoud-Collet J-P, Dubois C, et al. (2024) Musa species in mainland Southeast Asia: From wild to domesticate. PLoS ONE 19(10): e0307592. https://doi.org/10.1371/journal.pone.0307592