Introduction:

The Asparagaceae family includes several genera adapted to survive at high temperatures and with low water availability. These include Agave, Beaucarnea, Dasylirion, Nolina and Yucca. Mexico has a great biodiversity in these plant groups, as well as an ancestral tradition regarding its use. In vitro propagation systems are efficient for the production of these plants and can be used to perform various types of studies. Among these are the studies of tolerance to heavy metals, which can serve to determine which species are suitable for reforestation and regeneration of areas contaminated by mining activities.

Method:

In this work, 20 species of the family Asparagaceae were propagated in vitro and their rooting process was evaluated in culture media added with Cd, Cu, Cr, Fe, Mn, Pb and Zn. The development of roots in the presence of these metals was analyzed and its absorption capacity was determined by flame atomic absorption spectrophotometry. With these data, translocation and bioaccumulation factors were calculated in order to characterize the response of each species to heavy metals.

Results:

The highest number of shoots occurred in the species Beaucarnea recurvata, which generated 5.7 shoots per explant and Nolina durangensis with 5.6. Chromium treatment was toxic for most species. Agave celsii, A. chiapensis, A. obscura, A. palmeri and A. salmiana formed roots in all treatments. According to translocation and bioaccumulation factors, the analyzed species were classified as phytostabilizers, exclusors, bioaccumulators and indicators. The species A. chiapensis, A. obscura and A. palmeri were bioaccumulators for Mn. A. celsii and A. salmiana presented mechanisms of phytostabilization and exclusion.

Conclusion:

In vitro propagation allows to work and study a wide range of species in the presence of contaminants. The Agave genus is tolerant to metals and can be used to phytostabilize and remediate contaminated soils.

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