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Sex ratio, size distribution and nitrogen resorption in the dioecious tree species Bursera morelensis (Burseraceae)

Published online by Cambridge University Press:  01 July 2008

Numa P. Pavón*
Affiliation:
Centro de Investigaciones Biológicas, Universidad Autónoma del Estado de Hidalgo, A.P. 69, Pachuca, Hidalgo, C.P. 42001, Mexico
Irving de Luna Ramírez
Affiliation:
Centro de Investigaciones Biológicas, Universidad Autónoma del Estado de Hidalgo, A.P. 69, Pachuca, Hidalgo, C.P. 42001, Mexico
*
1Corresponding author. Email: npavon@uaeh.edu.mx

Extract

Dioecious plant populations have generally been considered to maintain sex ratios of 1:1 (Allen & Antos 1993, Carroll & Mulcahy 1993, Charnov 1982). The sex ratio does, however, change if the plants are growing in a stressful environment, often being male-biased under these conditions (Ortiz et al. 1998, 2002). This pattern has been explained by differences in how the sexes resolve their respective energy requirements (Obeso et al. 1998). Females generally assign more resources to reproduction in comparison to growth and maintenance than do males, and they are smaller and longer-lived (Allen & Antos 1993, Nicotra 1999, Obeso et al. 1998, Willson 1983). Thus their higher reproductive costs take a toll on females, modifying the population sex ratio in favour of males (Allen & Antos 1993, Lovett-Doust & Lovett-Doust 1988). However, in order to determine the reproductive cost it is necessary to consider the compensatory mechanisms (Obeso 2002). These reduce the reproductive cost and include plastic response in terms of plant architecture and plant physiology. For example, nutrient resorption is a process that may help decrease dependence on nutrient intake, thereby constituting an important nutrient economy mechanism that can also reduce the reproductive cost if a significant proportion of the nutrients had been reassigned to reproduction (Killingbeck 1986, Obeso 2002).

Type
Short Communication
Copyright
Copyright © Cambridge University Press 2008

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References

LITERATURE CITED

AERTS, R. 1996. Nutrient resorption from senescing leaves of peren-nials: are there general patterns? Journal of Ecology 84:597608.CrossRefGoogle Scholar
ALLEN, G. A. & ANTOS, J. A. 1993. Sex ratio variation in the dioecious shrub Oemleria cerasiformis. American Naturalist 141:537553.CrossRefGoogle ScholarPubMed
BIERZYCHUDEK, P. & ECKHART, V. 1988. Spatial segregation of the sexes of dioecious plants. American Naturalist 132:3443.CrossRefGoogle Scholar
CAI, Z. & BONGERS, F. 2007. Contrasting nitrogen and phosphorus resorption efficiencies in trees and lianas from a tropical montane rain forest in Xishuangbanna, south-west China. Journal of Tropical Ecology 23:1118.CrossRefGoogle Scholar
CARDENAS, I. & CAMPO, J. 2007. Foliar nitrogen and phosphorus resorption and decomposition in the nitrogen-fixing tree Lysiloma microphyllum in primary and secondary seasonally tropical dry forests in Mexico. Journal of Tropical Ecology 23:1013.CrossRefGoogle Scholar
CARROLL, S. B. & MULCAHY, D. L. 1993. Progeny sex ratio in dioecious Silene latifolia (Caryophyllaceae). American Journal of Botany 80:5556.CrossRefGoogle ScholarPubMed
CHARNOV, E. L. 1982. The theory of sex allocation. Princeton University Press, Princeton. 355 pp.Google ScholarPubMed
CIPOLLINI, M. L. & STILES, E. W. 1991. Costs of reproduction in Nyssa sylvatica: sexual dimorphism in reproductive frequency and nutrient flux. Oecologia 86:585593.CrossRefGoogle ScholarPubMed
DAWSON, T. E. & EHLERINGER, J. R. 1993. Gender-specific physiology, carbon isotope discrimination, and habitat distribution in boxelder, Acer negundo. Ecology 74:798815.CrossRefGoogle Scholar
FREEMAN, D. C., MCARTHUR, E. D., SANDERSON, S. C. & TIEDEMAN, A. R. 1993. The influence of topography on male and female fitness components of Atriplex canescens. Oecologia 93:538547.CrossRefGoogle ScholarPubMed
KILLINGBECK, K. T. 1986. The terminological jungle revisited: making a case for use of the term resorption. Oikos 42:263264.CrossRefGoogle Scholar
KILLINGBECK, K. T. & COSTIGAN, S. A. 1988. Element resorption in a guild of understory shrub species: niche differentiation and resorption thresholds. Oikos 53:366374.CrossRefGoogle Scholar
LOVETT-DOUST, J. & LOVETT-DOUST, L. 1988. Modules of production and reproduction in a dioecious clonal shrub, Rhus typhina. Ecology 69:741750.CrossRefGoogle Scholar
NICOTRA, A. B. 1999. Reproductive allocation and the long-term costs of reproduction in Siparuna grandiflora, a dioecious neo-tropical shrub. Journal of Ecology 87:138149.CrossRefGoogle Scholar
OBESO, J. R. 1997. Costs of reproduction in Ilex aquifolium: effects at tree, branch and leaf level. Journal of Ecology 85:159166.CrossRefGoogle Scholar
OBESO, J. R. 2002. The costs of reproduction in plants. New Phytologist 155:3248.CrossRefGoogle ScholarPubMed
OBESO, J. R., ALVAREZ-SANTULLANO, M. & RETUERTO, R. 1998. Sex ratios, size distributions, and sexual dimorphism in the dioecious tree Ilex aquifolium (Aquifoliaceae). American Journal of Botany 85:16021608.CrossRefGoogle ScholarPubMed
ORTIZ, P. L., ARISTA, M. & TALAVERA, S. 1998. Low reproductive success in two subspecies of Juniperus oxycedrus L. International Journal of Plant Sciences 159:843847.CrossRefGoogle Scholar
ORTIZ, P. L., ARISTA, M. & TALAVERA, S. 2002. Sex ratio and reproductive effort in the dioecious Juniperus communis subsp. alpina (Suter) Celak. (Cupressaceae) along an altitudinal gradient. Annals of Botany 89:205211.CrossRefGoogle ScholarPubMed
PAVÓN, N. P., BRIONES, O. & FLORES-RIVAS, J. 2005. Litterfall production and nitrogen content in an intertropical semi-arid Mexican scrub. Journal of Arid Environments 60:113.CrossRefGoogle Scholar
PUIG, H. 1991. Vegetación de la Huasteca Mexico: estudio fitogeográfico y ecológico. ORSTOM, Instituto de Ecología, CEMCA, Mexico City. 625 pp.Google Scholar
RAMADAN, A. A., EL-KEBLAWY, A., SHALTOUT, K. H. & LOVETT-DOUST, J. 1994. Sexual polymorphism, growth, and reproductive effort in Egyptian Thymelaea hirsuta (Thymelaeaceae). American Journal of Botany 81:847857.CrossRefGoogle Scholar
RENTERÍA, L. Y., JARAMILLO, V. J., MARTÍNEZ-YRIZAR, A. & PÉREZ-JIMÉNEZ, A. 2005. Nitrogen and phosphorus resorption in trees of a Mexican tropical dry forest. Trees 19:431441.CrossRefGoogle Scholar
VASILIAUSKAS, S. A. & AARSSEN, L. W. 1992. Sex ratio and neighbor effects in monospecific stands of Juniperus virginiana. Ecology 73:622632.CrossRefGoogle Scholar
WILLSON, M. F. 1983. Plant reproductive ecology. Wiley, New York. 282 pp.Google Scholar
ZAR, J. H. 1999. Biostatistical analysis. Prentice Hall, New Jersey. 663 pp.Google Scholar