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Producción de semillas de caoba en México Patrones de variación e implicaciones para la sostenibilidad1

Recursos Naturales y Ambiente 03/2005; 44:2005.

ABSTRACT Durante seis años se cuantificó la producción anual
de frutos de 82 árboles de caoba en la selva de
Quintana Roo, México; para ello, se contaron los
segmentos de frutos caídos debajo de las copas.
Los árboles muestreados medían de <20 cm a
≥100 cm dap. Los árboles de ≥75 cm dap produjeron
significativamente más frutos que los árboles
más pequeños, hasta >700 frutos/árbol. Los
árboles ≥75 cm también produjeron de manera
más consistente. Mientras que hasta 30% de los
árboles de <75 cm produjeron 0 frutos en un año
dado, en promedio, 90% de los árboles grandes
produjeron frutos cada año. Durante los seis años,
cada árbol de ≥75 cm dap produjo un total de 367
± 34 frutos, comparado con 91 ± 8 frutos/árbol
entre los árboles de <75 cm (un total de 61 ± 7
y 15 ± 2 frutos/árbol/año, respectivamente). La
producción varió entre años; en 1998 se obtuvo la
mayor producción y en 1999 y 2000 la más baja.
Los árboles grandes produjeron cinco veces más
frutos en los años de alta producción que en los
años de menor producción. Para asegurar que
haya fuentes de semilla para la regeneración de la
caoba, ya sea natural o por siembra o plantación,
hace falta proteger árboles semilleros grandes.
Esto es un reto, ya que el diámetro mínimo de corta
para la caoba en Quintana Roo es de 55 cm.
Palabras claves: Caoba; Swietenia macrophylla;
semillas; fructificación; regeneración; sostenibilidad;
México.
Production of mahogany seed in Mexico:
patterns of variation and implication for sustainability.
Fruit production by 82 mahogany trees
growing in natural forests was sampled by counting
woody fruit capsule segments that fell below their
crowns during each of 6 successive years. Sample
trees growing in central Quintana Roo, Mexico,
ranged from <20 cm to more than 100 cm DBH.
Trees ≥75 cm produced significantly more fruits
each year than did trees of smaller diameters. Large
trees could produce more than 700 fruits/year.
Trees ≥75 cm DBH were also more consistent
producers: while up to 30% of trees <75 cm DBH
produced <1 fruit/year in any year, an average of
90% of larger trees produced fruit every year. Over
the 6 years, individual trees ≥75 cm produced a
total of 367 ± 34 fruits, as compared to 91 ± 8 fruits
among trees <75 cm (an average of 61 ± 7 and 15
± 2 fruits/yr, respectively). Fruit production varied
among years, with the highest production in 1998
and the lowest in 1999 and 2000. The largest trees
produced 5 times more fruit in the year of highest
production than in the lowest. To ensure that seed
production potential is sustained, it is important
to protect mahogany trees ≥75 cm DBH as seed
sources. This represents a challenge, since the
minimum cutting diameter in the production forests
of the region is 55 cm DBH.
Keywords: Mahogany; Swietenia macrophylla;
seeds; fruiting; regeneration; sustainability; México.

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