TY - JOUR
T1 - Allocation to defense or growth in dipterocarp forest seedlings in Borneo
AU - Kurokawa, Hiroko
AU - Kitahashi, Yoshinori
AU - Koike, Takayoshi
AU - Lai, Julaihi
AU - Nakashizuka, Tohru
N1 - Funding Information:
Acknowledgements We express our thanks to Dr. H. S. Lee, Mr. A. A. Hamid, Ms. Lucy Chong, Mr. Ahamad and the staff of the Forest Research Center in Sarawak for kindly arranging this project. We also thank the Sarawak Biodiversity Center for permission to undertake this research in Sarawak. We appreciate Dr. M. Hori for teaching us the techniques of chemical analyses and Mr. D. Hembry for improving English in this manuscript. The Japan Science and Technology Corporation (CREST) and the Ministry of Education, Science, Sports, and Culture, Japan, (09NP1501) partly funded this study.
PY - 2004/7
Y1 - 2004/7
N2 - We quantified the allocation of net production to plant secondary metabolites (especially condensed tannins and lignins) to evaluate the investment into defense mechanisms of three tropical forest canopy species in Borneo vis-à-vis the resource availability hypothesis. In particular, we focused on Borneo ironwood (Eusideroxylon zwageri, Lauraceae), which seemed to employ an extreme defensive strategy. The wood of this species is extremely durable and has a high specific gravity with a very slow growth rate. The allocation to defense by Borneo ironwood was compared to two emergent species of Dipterocarpaceae, the dominant family in this forest community. We conducted shade-house experiments on seedlings under four controlled conditions (two light levels x two nutrient levels) and showed that the growth rate of E. zwageri was much lower than those of the other two species, and it allocated more of its net production to leaves and roots than to stems. The concentrations of condensed tannins and lignins were very high in the leaves and stems of this species, at about 20 and 30%, respectively. In total, E. zwageri allocated a maximum of about 35% of its net production to defensive substances (i.e., condensed tannins + lignins). In contrast, the two dipterocarp species allocated about 20-25% of their net production to defensive substances. The condensed tannins in E. zwageri help to prolong the lifespan of the leaves, and the lignins in the stems enhance the durability of the wood. Thus, although E. zwageri grows very slowly, the allocation to defensive substances seems to be an advantageous strategy for survival under dark conditions.
AB - We quantified the allocation of net production to plant secondary metabolites (especially condensed tannins and lignins) to evaluate the investment into defense mechanisms of three tropical forest canopy species in Borneo vis-à-vis the resource availability hypothesis. In particular, we focused on Borneo ironwood (Eusideroxylon zwageri, Lauraceae), which seemed to employ an extreme defensive strategy. The wood of this species is extremely durable and has a high specific gravity with a very slow growth rate. The allocation to defense by Borneo ironwood was compared to two emergent species of Dipterocarpaceae, the dominant family in this forest community. We conducted shade-house experiments on seedlings under four controlled conditions (two light levels x two nutrient levels) and showed that the growth rate of E. zwageri was much lower than those of the other two species, and it allocated more of its net production to leaves and roots than to stems. The concentrations of condensed tannins and lignins were very high in the leaves and stems of this species, at about 20 and 30%, respectively. In total, E. zwageri allocated a maximum of about 35% of its net production to defensive substances (i.e., condensed tannins + lignins). In contrast, the two dipterocarp species allocated about 20-25% of their net production to defensive substances. The condensed tannins in E. zwageri help to prolong the lifespan of the leaves, and the lignins in the stems enhance the durability of the wood. Thus, although E. zwageri grows very slowly, the allocation to defensive substances seems to be an advantageous strategy for survival under dark conditions.
KW - Condensed tannins
KW - Lignins
KW - Net production
KW - Resource availability
KW - Tropical rain forests
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U2 - 10.1007/s00442-004-1566-7
DO - 10.1007/s00442-004-1566-7
M3 - Article
C2 - 15179575
AN - SCOPUS:3843128517
VL - 140
SP - 261
EP - 270
JO - Oecologia
JF - Oecologia
SN - 0029-8519
IS - 2
ER -