Keywords
photoinhibition
photosynthesis
psychotria limonensis
tropical forest
Panama
fluorescencia
clorofila
fotoinhibicion
fotosintesis
psychotria limonensis
bosque tropical
Panama
How to Cite
Abstract
We explored the short-term adjustment in photochemical efficiency (Fv/Fm) in adult and young leaves of the understory neotropical shrub Psychotria limonensis Krause (Rubiaceae) in response to rapid changes in the light environment. Leaves were collected from 20 individual plants growing under sun and shade conditions on Gigante Peninsula, Barro Colorado Natural Monument (Republic of Panama), during the wet season of 1996. Leaves were distributed in four sequences of light treatments (AB leaves were expanded under sun and were transferred to shade, BA leaves experienced the opposite transfer, and the controls AA and BB leaves that were expanded and maintained under sun or shade conditions). Adult and young leaves did not differ in overall photochemical efficiency. Instead, differences were found among light environments, for which leaves transferred from shade to sun showed the lowest Fv/Fm ratios. There was no relationship between photochemical efficiency and leaf temperature. In P. limonensis, understory plants are susceptible of photoinhibition independently of the leaf ontogenetic stage. The approach utilized in this experiment allowed the rapid exploration of this capacity, and could be applied to poorly studied understory speciesReferences
Araus, J.L. & K.P. Hogan. 1994. Leaf structure and patterns of photoinhibition in two neotropical palms in clearings and forest understory during the dry season. Am. J. Bot. 81: 726-738.
Avalos, G. 1999. Photosynthetic acclimation of canopy branches and seedlings of lianas to light changes in a tropical dry forest. Ph.D. Thesis. University of Missouri-St. Louis, St. Louis Missouri.
Avalos, G. & S.S. Mulkey. 1999. Photosynthetic acclimation of the liana Stigmaphyllon lindenianum to light changes in a tropical dry forest. Oecologia 120: 475-484.
Barone, J.A. 1998. Effects of light availability and rainfall on leaf production in a moist tropical forest in central Panama. J. Trop. Ecol. 14: 309-321.
Bauer, H. & W. Thöni. 1988. Photosynthetic light acclimation in fully developed leaves of the juvenile and adult life phases of Hedera helix. Physiol. Plant. 73: 31-37.
Bazzaz, F.A. & R.W. Carlson. 1982. Photosynthetic acclimation to variability in the light environment of early and late successional plants. Oecologia 54: 313-316.
Chazdon, R.L. & N. Fetcher. 1984. Photosynthetic light environments in a lowland tropical rain forest in
Costa Rica. J. Ecol. 72: 553-564.
Chazdon, R.L., R.W. Pearcy, D.W. Lee & N. Fetcher. 1996. Photosynthetic responses of tropical forest plants to contrasting light environments. p. 5-55. In S.S. Mulkey, R.L. Chazdon & A.P. Smith (eds.). Tropical Forest Plant Ecophysiology. Chapman & Hall, New York.
Croat, T.B. 1978. Flora of Barro Colorado Island. Stanford University Press, Stanford, CA.
Demmig, B. & O. Björkman. 1987. Comparison of the effect of excessive light on chlorophyll fluorescence (77 K) and photon yield of O2 evolution in leaves of higher plants. Planta 71: 171-184.
Denslow, J.S. 1980. Gap Partitioning among Tropical Rainforest Trees. Biotropica 12: 47-55.
Denslow, J. S. 1987. Tropical rainforest gaps and tree species diversity. Ann. Rev. Ecol. Syst. 18: 432-451.
Dickson, R.E. & J.G. Isebrands. 1991. Leaves as regulators of stress response. p. 3-34. In H.A. Mooney, W.E. Winner, E.J. Pell & E. Chu (eds.). Response of Plants to Multiple Stresses. Academic, New York.
Fernández, D. & N. Fetcher. 1991. Chlorophyll fluorescence and quantum yield in seedlings and saplings of tropical forest. Primer Congreso Venezolano de Ecología. Resúmenes, Sociedad Venezolana de Ecología, Caracas.
Fetcher, N., S.F. Oberbauer & R.L. Chazdon. 1994. Physiological Ecology of Plants. p. 128-141. In L.A.
McDade, K.S. Bawa, H.A. Hespenheide & G.S. Hartshorn (eds.). La Selva: Ecology and Natural
History of a Neotropical Rain Forest. University of Chicago, Chicago.
Field, C.B. 1991. Ecological Scaling of Carbon Gain to Stress and Resource Availability. p. 35-63. In H.A.
Mooney, W.E. Winner & E.J. Pell (eds.). Response of Plants to Multiple Stresses. Academic, New York.
Grubb, P.J. 1977. The maintenance of species richness in plant communities: the importance of the regeneration niche. Biol. Rev. 52: 107-145.
Gouallec, J.L.L., G. Cornic & P. Blanc. 1990. Relations between sunfleck sequences and photoinhibition of photosynthesis in a tropical rain forest understory herb. Amer. J. Bot. 77: 999-1006.
Gouallec, J.L.L., G. Cornic & J.M. Briantais. 1991. Chlorophyll fluorescence and photoinhibition in a tropical rainforest understory plant. Photosynthesis Res. 27: 135-142.
Kitajima, K., S.S. Mulkey & S.J. Wright. 1997. Seasonal leaf phenotypes in the canopy of tropical dry forest: photosynthetic characteristics and associated traits. Oecologia 109: 409-498.
Krause, G.H. 1988. Photoinhibition of photosynthesis. An evaluation of damaging and protective mechanisms. Physiol. Plantarum 74: 566-574.
Krause, G.H., A. Virgo & K. Winter. 1995. High susceptibility to photoinhibition of young leaves of tropical forest trees. Planta 197: 583-591.
Long, S.P., S. Humphries & P.G. Falkowski. 1994. Photoinhibition of photosynthesis in nature. Annu.
Rev. Plant Physiol. Mol. Biol. 45: 633-662.
Lovelock, C. E, M. Jebb & C.B. Osmond. 1994. Photoinhibition and recovery in tropical plant species:
response to disturbance. Oecologia 97: 297-307.
Mulkey, S.S. & R.W. Pearcy. 1992. Interactions between acclimation and photoinhibition of photosynthesis of a tropical forest understory herb: Alocasia macrorrhiza, during simulated canopy gap formation. Functional Ecol. 6: 719-729.
Osmond, C.B. 1981. Photorespiration and photoinhibition: some implications for the energetics of photosynthesis. Biochim. Biophys Acta. 639: 77-98.
Wright, S.J., J.L. Machado, S.S. Mulkey & A.P. Smith. 1992. Drought acclimation among tropical forest
shrubs (Psychotria, Rubiaceae). Oecologia 89: 457-463.
Wright , S.J. 1996. Phenological responses to sasonality in tropical forest plants. p. 440-60. In S.S. Mulkey, R. Chazdon & A. Smith (eds). Tropical Forest Plan Ecophysiology. Chapman & Hall, New York.
Comments
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright (c) 2004 Revista de Biología Tropical