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Contrasting herbivory patterns and leaf fluctuating asymmetry in Heliocarpus pallidus between different habitat types within a Mexican tropical dry forest

Published online by Cambridge University Press:  31 May 2011

Pablo Cuevas-Reyes ,
Ken Oyama ,
Antonio González-Rodríguez ,
G. Wilson Fernandes  and
Luis Mendoza-Cuenca
Pablo Cuevas-Reyes*
Affiliation:
Laboratorio de Ecología de Interacciones Bióticas, Facultad de Biología, Universidad Michoacana de San Nicolás de Hidalgo Ciudad Universitaria, Morelia, Michoacán, México, C.P. 58060 Ecologia Evolutiva & Biodiversidade/DBG, C P 486, ICB/Universidade Federal de Minas Gerais, UFMG, 31270 901 Belo Horizonte, MG, Brazil
Ken Oyama
Affiliation:
Centro de Investigaciones en Ecosistemas, Universidad Nacional Autónoma de México (UNAM), Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, Morelia, 58190, Michoacán, México
Antonio González-Rodríguez
Affiliation:
Centro de Investigaciones en Ecosistemas, Universidad Nacional Autónoma de México (UNAM), Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, Morelia, 58190, Michoacán, México
G. Wilson Fernandes
Affiliation:
Ecologia Evolutiva & Biodiversidade/DBG, C P 486, ICB/Universidade Federal de Minas Gerais, UFMG, 31270 901 Belo Horizonte, MG, Brazil
Luis Mendoza-Cuenca
Affiliation:
Laboratorio de Ecología de la Conducta, Facultad de Biología, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Morelia, Michoacán, México, C.P. 58060
*
1Corresponding author. Email: pcuevas@oikos.unam.mx
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Abstract:

Leaf fluctuating asymmetry (FA) is considered an important indicator of environmentally induced stress in plants, but the relationship between herbivory and FA levels is not clear. In this study we compared leaf size and shape, leaf area consumed by herbivorous insects, and FA levels between individuals of Heliocarpus pallidus (Tiliaceae) from two adjacent and contrasting habitat types (deciduous and riparian) in the Chamela–Cuixmala tropical dry-forest biosphere reserve. Ten individuals of H. pallidus were collected in each habitat type. Leaf shape was assessed using geometric morphometric techniques. Results indicated statistically significant differences in leaf shape between individuals from the two habitat types. In individuals from the riparian habitat leaf area (mean = 42.3 ± 1.2 cm2), herbivory levels (mean = 25.5% ± 1.8%) and FA levels (mean = 0.38 ± 0.04 cm) were significantly higher than in individuals from the deciduous habitat (17.2 ± 3.5 cm2; 9.6% ± 1.0% and 0.18 ± 0.04 cm, respectively). Within habitats, significant correlations were found between total leaf area and percentage leaf area removed by insects (R2 = 0.92 in riparian habitats, R2 = 0.9 in deciduous habitats), and between percentage leaf area removed and FA (R2 = 0.70 in riparian habitats, R2 = 0.79 in deciduous habitats). As has been suggested for other plant species, it is possible that the more favourable conditions in the riparian habitat enhance leaf growth, resulting in higher FA. Also, individuals in this habitat might be characterized by lower chemical defence and/or higher nutritional quality, which would explain the higher herbivory levels.

Keywords

fluctuating asymmetrygeometric morphometricsherbivoryleaf sizetropical dry forest
Type
Research Article
Information
Journal of Tropical Ecology , Volume 27 , Issue 4 , July 2011 , pp. 383 - 391
Copyright
Copyright © Cambridge University Press 2011

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References

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