DOI QR코드

DOI QR Code

Responses of different phytoelements to habitat light level and their dynamic convergence towards crown development of Aucuba japonica Thunb. var. japonica

  • Received : 2012.02.04
  • Accepted : 2012.06.07
  • Published : 2012.09.01

Abstract

We analyzed crown development in Aucuba japonica Thunb. var. japonica resulting from the responses of phytoelements to habitat light conditions over a long period of time. Over the years, the degree of extension unit (EU) dimorphism and the degree of anisophylly were higher under shaded conditions than in brighter conditions. An overall temporally increasing pattern in the degree of EU dimorphism was found while no clear-cut trend was found in the case of anisophylly. EU length and number of leaves per EU co-varied in a spatio-temporal context. The number of terminal buds and their sizes acted as the key initiators of morphological differences of phytoelements which were further amplified following bud break. Leaf area density was displayed mostly in the apex peripheral layer of the crown and the apex layer received most of the incident light. There was a tradeoff between annual leaf production and mean leaf size. Depending on the heterogeneity of irradiance level within a crown, correlative growth inhibition caused higher EU mortality at brighter sites. Due to high mortality, shorter EUs had a mere role in the construction of structural framework of the crown except for the formation of some gaps. There was a strong convergence of EU dimorphism, anisophylly, EU extension growth and variations in leaf size towards formation of functional crown to reduce potential self-shading. Depending on the irradiance level, Aucuba japonica Thunb. var. japonica showed two different modes of crown expansion. At the brighter sites, individual crown expansion was progressive while at the darker sites, individual crown expanded in a diminishing manner and maintained a stable size. A plant's "growth diminishing phase" appeared earlier at shaded sites than brighter sites.

Keywords

References

  1. Ali MS, Kikuzawa K. 2005a. Anisophylly in Aucuba japonica (Cornaceae): an outcome of spatial crowding in the bud. Can J Bot 83: 143-154. https://doi.org/10.1139/b04-157
  2. Ali MS, Kikuzawa K. 2005b. Plasticity in leaf-area density within the crown of Aucuba japonica growing under different light levels. J Plant Res 118: 307-316. https://doi.org/10.1007/s10265-005-0222-6
  3. Ali MS, Kikuzawa K. 2005c. Shoot morphology of Aucuba japonica incurred by anisophylly: ecological implications. J Plant Res 118: 329-338. https://doi.org/10.1007/s10265-005-0230-6
  4. Andersen PC, Knox GW, Norcini JG. 1991. Light intensity influences growth and leaf physiology of Aucuba japonica 'Variegata'. Hortscience 26: 1485-1488.
  5. Givnish TJ. 1984. Leaf and canopy adaptations in tropical forests. In: Physiological Ecology of Plants of the Wet Tropics (Medina E, Mooney HA, Vazquez-Yanes C, eds). W. Junk, The Hague, pp 51-84.
  6. Goebel K. 1900. Organography of Plants. Oxford University Press, Oxford.
  7. Halle F, Oldeman RAA, Tomlinson PB. 1978. Tropical Trees and Forests: An Architectural Analysis. Springer-Verlag, Berlin.
  8. Hara N. 1980. Shoot development of Aucuba japonica I. Morphological study. Bot Mag Tokyo 93: 101-116. https://doi.org/10.1007/BF02489117
  9. Hatakeyama I, Murata G, Tabata H. 1973. A list of plants in the botanical garden of Kyoto University and some ecological data. Mem Fac Sci Kyoto Univ Biol 6: 91-148.
  10. Hiura T. 1998. Shoot dynamics and architecture of sapling in Fagus crenata across its geographical range. Tress 12: 274-280.
  11. Ishihara M, Kikuzawa K. 2004. Species-specific variation in shoot production patterns of five birch species with respect to vegetative and reproductive shoots. Can J Bot 82: 1393-1401. https://doi.org/10.1139/b04-099
  12. Ishihara MI, Kikuzawa K. 2009. Annual and spatial variation in shoot demography associated with masting in Betula grossa: comparison between mature trees and saplings. Ann Bot 104: 1195-1205. https://doi.org/10.1093/aob/mcp217
  13. Ishii H, Asano S. 2010. The role of crown architecture, leaf phenology and photosynthetic activity in promoting complementary use of light among coexisting species in temperate forests. Ecol Res 25: 715-722. https://doi.org/10.1007/s11284-009-0668-4
  14. Isobe H, Kikuchi T. 1989. Differences in shoot form and age of Aucuba japonica Thunb. corresponding to the microlandforms on a hill slope. Ecol Rev 21: 277-281.
  15. Jones M, Harper JL. 1987. The influence of neighbours on the growth of trees. II. The fate of buds on long and short shoots in Betula pendula. Proc R Soc Lond B 232: 19-33. https://doi.org/10.1098/rspb.1987.0059
  16. Kikuzawa K, Yagi M, Ohto Y, Umeki K, Lechowicz MJ. 2009. Canopy ergodicity: can a single leaf represent an entire plant canopy? Plant Ecol 202: 309-323. https://doi.org/10.1007/s11258-008-9486-y
  17. Kume A, Ino Y. 2000. Differences in shoot size and allometry between two evergreen broad-leaved shrubs, Aucuba japonica varieties in two contrasting snowfall habitats. J Plant Res 113: 353-363. https://doi.org/10.1007/PL00013942
  18. Maillette L. 1982. Structural dynamics of silver birch. I. The fates of buds. J Appl Ecol 19: 203-218. https://doi.org/10.2307/2403005
  19. Muraoka H, Koizumi H, Pearcy RW. 2003. Leaf display and photosynthesis of tree seedlings in a cool-temperate deciduous broadleaf forest understorey. Oecologia 135: 500-509. https://doi.org/10.1007/s00442-003-1227-2
  20. Niinemets U. 2010. A review of light interception in plant stands from leaf to canopy in different plant functional types and in species with varying shade tolerance. Ecol Res 25: 693-714. https://doi.org/10.1007/s11284-010-0712-4
  21. Osada N, Takeda H, Furukawa A, Awang M. 2002. Changes in shoot allometry with increasing tree height in a tropical canopy species, Elateriospermum tapos. Tree Physiol 22: 625-632. https://doi.org/10.1093/treephys/22.9.625
  22. Seiwa K, Kikuzawa K, Kadowaki T, Akasaka S, Ueno N. 2006. Shoot life span in relation to successional status in deciduous broad-leaved tree species in a temperate forest. New Phytol 169: 537-548. https://doi.org/10.1111/j.1469-8137.2005.01608.x
  23. Stoll P, Schmid B. 1998. Plant foraging and dynamic competition between branches of Pinus sylvestris in contrasting light environments. J Ecol 86: 934-945. https://doi.org/10.1046/j.1365-2745.1998.00313.x
  24. Takenaka A. 2000. Shoot growth responses to light microenvironment and correlative inhibition in tree seedlings under a forest canopy. Tree Physiol 20: 987-991. https://doi.org/10.1093/treephys/20.14.987
  25. Takenaka A, Inui Y, Osawa A. 1998. Measurement of threedimensional structure of plants with a simple device and estimation of light capture of individual leaves. Funct Ecol 12: 159-165. https://doi.org/10.1046/j.1365-2435.1998.00171.x
  26. Tremmel DC, Bazzaz FA. 1993. How neighbor canopy architecture affects target plant performance. Ecology 74: 2114-2124. https://doi.org/10.2307/1940856
  27. van Volkenburgh E. 1999. Leaf expansion: an integrating plant behaviour. Plant Cell Environ 22: 1463-1473. https://doi.org/10.1046/j.1365-3040.1999.00514.x
  28. Whitney GG. 1976. The bifurcation ratio as an indicator of adaptive strategy in woody plant species. Bull Torrey Bot Club 103: 67-72. https://doi.org/10.2307/2484833
  29. Yagi T, Kikuzawa K. 1999. Patterns in size-related variations in current-year shoot structure in eight deciduous tree species. J Plant Res 112: 343-352. https://doi.org/10.1007/PL00013862
  30. Yamada T, Okuda T, Abdullah M, Awang M, Furukawa A. 2000. The leaf development process and its significance for reducing self-shading of a tropical pioneer tree species. Oecologia 125: 476-482. https://doi.org/10.1007/s004420000473
  31. Yamamura Y. 1986. Matter-economical roles of the evergreen foliage of Aucuba japonica, an understory shrub in the warm-temperate region of Japan. 1. Leaf demography, productivity and dry matter economy. Bot Mag Tokyo 99: 323-332. https://doi.org/10.1007/BF02488713
  32. Yano S, Terashima I. 2004. Developmental process of sun and shade leaves in Chenopodium album L. Plant Cell Environ 27: 781-793. https://doi.org/10.1111/j.1365-3040.2004.01182.x