Sisal/Agave - Industrial Crops: Breeding for BioEnergy and Bioproducts - page 342

plant, typically on a 3-month cycle to provide a continuous supply of material for
processing [ 5 ]. Again, this has been dependent on manual labor, which could
benefit rural economies of the poorest potential producer countries. However,
elsewhere this is likely to be economically inefficient. As noted above, both
mechanical harvesters and mechanical aids to manual harvesting could be devel-
oped [ 21 , 22 ].
Another challenge for widespread adoption of Agave for bioenergy is the
establishment time. Agave plants take at least 5 years to mature. In the case of
those grown for fiber, harvesting of the leaves may occur annually (after ~3 years
establishment) for up to 15 years before replanting is required. In the case of Agave
that would be harvested for easily fermented sugars, however, the entire plants are
harvested and the field must be replanted following the harvest cycle of 5-7 years.

Opportunities

Despite the novelty and challenges associated with the agricultural production of
Agave for bioenergy, this genus has many traits desirable for feedstock and there is
a rare, perhaps unique, land opportunity associated with Agave. With 18 % of the
global land surface in semiarid land that does not intersect with prime agricultural
lands, and recent abandonment of agriculture for sisal production, there is an
opportunity to develop Agave feedstocks with less controversy than was experi-
enced for current ethanol feedstocks. Indeed, not only could Agave provide biofuel
if placed on semiarid abandoned land, without conflict with current food supply, but
it could aid in reversing the human-induced degradation of much of this land area,
by adding organic matter and stabilizing soil surfaces.

References

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Community. In: Fish SK, Fish PR, Madsen JH, editors. The Marana community in the
Hohokam world. Tucson: The University of Arizona Press; 1992. p. 73-81.
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ancestral hay futuro: del tequila, los mezcales y otros agaves. 1st ed. M´rida: Centro de
Investigaci´n Cient´fica de Yucat´n, A.C.; 2007.
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