Abstract
Rapid germination of non-dormant seeds is one adaptation plants have evolved to counter seed predation by rodents. Some rodent species have evolved behaviors that prevent or slow the seed germination process through seed embryo removal or seed pruning; however, no plant species is known to have successfully escaped embryo removal or seed pruning by rodents. Here, we report that the non-dormant seeds of Pittosporopsis kerrii Craib in tropical rain forests in China have a high regeneration capacity to counter seed pruning by rodents. We found seed pruning, instead of embryo removal, was commonly used by rodents to increase food storage time by slowing down the seed germination process, but that P. kerrii seeds have a high regeneration capacity to escape seed predation by rodents: all pruned seeds, pruned roots and embryo-removed seeds by rodents or people retain the ability to develop into seedlings. Seeds of P. kerrii also have other capacities (i.e. rapid seed decomposition and indigestible dormant taproots) to escape predation by reducing the plant’s attractiveness to rodents. The association between seed pruning behavior in rodents and high regeneration capacity of pruned seeds or roots in P. kerrii seeds are likely novel adaptation strategies adopted by seeds and rodents, respectively.
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Acknowledgments
This work was supported by the grant of National Natural Science Foundation (grant no. 30930016), the State Basic Research Program (grant no. 2007CB109102), and the CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences. We are grateful to the Xishuangbanna Station of Tropical Rainforest Ecosystem Studies for support in field work and for providing vegetation data of the study sites. We are thankful to Prof. Michael Steel, Wilkes University, and Prof. Stephen B. Vander Wall, University of Nevada, for providing valuable comments after reviewing an earlier version of this manuscript. Dr. Guangshun Jiang provided help in conducting statistical analysis.
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Communicated by Mark Chappell.
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Cao, L., Xiao, Z., Wang, Z. et al. High regeneration capacity helps tropical seeds to counter rodent predation. Oecologia 166, 997–1007 (2011). https://doi.org/10.1007/s00442-011-1908-1
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DOI: https://doi.org/10.1007/s00442-011-1908-1