Lessons from the history of Agave: ecological and cultural context for valuation of CAM

Abstract

Background and scope: Crassulacean acid metabolism (CAM) is an intriguing physiological adaptation in plants that are widespread throughout many ecosystems. Despite the relatively recent mechanistic understanding of CAM in plant physiology, evidence from historical records suggests that ancient cultures in the Americas also recognized the value of CAM plants. Agave species, in particular, have a rich cultural legacy that provides a foundation for commercially valued products. Here, we review that legacy and potential relationships between ancient values and the needs of modern-day climate adaptation strategies.

Conclusions: There are many products that can be produced from Agave species, including food, sugar, fibre and medicines. Traditional knowledge about agricultural management and preparation of plant products can be combined with new ecophysiological knowledge and agronomic techniques to develop these resources in the borderland region of the southwestern USA and Mexico. Historical records of pre-Columbian practices in the Sonoran desert and remnants of centuries-old agriculture in Baja California and Sonora demonstrate the climate resilience of Agave agriculture. Commercial growth of both tequila and bacanora indicates the potential for large-scale production today, but also underscores the importance of adopting regenerative agricultural practices to accomplish environmentally sustainable production. Recent international recognition of the Appellation of Origin for several Agave species produced for spirits in Mexico might provide opportunities for agricultural diversification. In contrast, fibre is currently produced from several Agave species on many continents. Projections of growth with future climate change suggest that Agave spp. will be viable alternatives for commodity crops that suffer declines during drought and increased temperatures. Historical cultivation of Agave affirms that these CAM plants can supply sugar, soft and hard fibres, medicines and food supplements.

Keywords: Agave americana; Agave angustifolia; Agave tequilana; bacanora; climate change; crassulacean acid metabolism; mescal; pre-Columbian; pulque; resilient agriculture; tequila; traditional knowledge.

Fig. 1.

Time lines of documented uses of Agave species for food (pink); fibre (blue); pulque and medicines (yellow); and mescals and other spirits with an Appellation of Origin in Mexico (grey).

Fig. 2.

Regional Appellation of Origins denoted with a heat map of density of occurrences (plant counts per kilometre squared) indicating centres of cultivation (in red) for Agave tequilana used for tequila (A) and Agave angustifolia used for bacanora (B) throughout Mexico. (Data source: GBIF, 2022; map generated with GADM CC-BY, https://gadm.org/license.html.)

Fig. 3.

Agave angustifolia plantation (A) and Agave salmania plantation (B) in Sonora Mexico (Coahuilo). These plantations are well known for high-yielding plants that produce aguamiel (Agave sap). In B, Nazario Gonzalez (owner) and Professor Antonio Hernandez are pictured inspecting the plants. (Photographs courtesy of Dr Jose Antonio Hernandez Herrera, Universidad Antonio Narro.)

Fig. 4.

Commercial plantation for bacanora with agroforestry and conservation of Agave angustifolia populations supported by FOBADES and the Borderlands Restoration Network in Sonora, Mexico (sign pictured on the left). Dr Hector Ortiz-Cano (right) and Daniel Moroyoqui (centre and right) are pictured at the Javier Figueroa plantation in Alamos, Sonora, Mexico.