Life-history constraints in grassland plant species: a growth-defence trade-off is the norm.

Plant growth can be limited by resource acquisition and defence against consumers, leading to contrasting trade-off possibilities. The competition-defence hypothesis posits a trade-off between competitive ability and defence against enemies (e.g. herbivores and pathogens). The growth-defence hypothesis suggests that strong competitors for nutrients are also defended against enemies, at a cost to growth rate. We tested these hypotheses using observations of 706 plant populations of over 500 species before and following identical fertilisation and fencing treatments at 39 grassland sites worldwide. Strong positive covariance in species responses to both treatments provided support for a growth-defence trade-off: populations that increased with the removal of nutrient limitation (poor competitors) also increased following removal of consumers. This result held globally across 4 years within plant life-history groups and within the majority of individual sites. Thus, a growth-defence trade-off appears to be the norm, and mechanisms maintaining grassland biodiversity may operate within this constraint.

[1]  P. Chesson.  Mechanisms of Maintenance of Species Diversity , 2000 .

[2]  M Henry H Stevens,et al.  The growth-defense trade-off and habitat specialization by plants in Amazonian forests. , 2006, Ecology.

[3]  B. Bolker,et al.  Spatial Moment Equations for Plant Competition: Understanding Spatial Strategies and the Advantages of Short Dispersal , 1999, The American Naturalist.

[4]  M. Wise,et al.  Effects of Resource Availability on Tolerance of Herbivory: A Review and Assessment of Three Opposing Models , 2007, The American Naturalist.

[5]  Helmut Hillebrand,et al.  Consumer versus resource control of producer diversity depends on ecosystem type and producer community structure , 2007, Proceedings of the National Academy of Sciences.

[6]  G. De’ath,et al.  CLASSIFICATION AND REGRESSION TREES: A POWERFUL YET SIMPLE TECHNIQUE FOR ECOLOGICAL DATA ANALYSIS , 2000 .

[7]  S. Sistla,et al.  Competition–defense tradeoffs and the maintenance of plant diversity , 2010, Proceedings of the National Academy of Sciences.

[8]  R Core Team,et al.  R: A language and environment for statistical computing. , 2014 .

[9]  A. Agrawal.  Current trends in the evolutionary ecology of plant defence , 2011 .

[10]  M. Westoby,et al.  Bivariate line‐fitting methods for allometry , 2006, Biological reviews of the Cambridge Philosophical Society.

[11]  P. Coley,et al.  The resource availability hypothesis revisited: a meta‐analysis , 2011 .

[12]  V. Eviner.  Plant trait responses to grazing – a global synthesis , 2006 .

[13]  M. Fischer,et al.  Tradeoffs associated with constitutive and induced plant resistance against herbivory , 2011, Proceedings of the National Academy of Sciences.

[14]  Daniel G. Milchunas,et al.  Plant trait responses to grazing – a global synthesis , 2007 .

[15]  F. S. Chapin,et al.  The Mineral Nutrition of Wild Plants , 1980 .

[16]  Andy Hector,et al.  Competition for Light Causes Plant Biodiversity Loss After Eutrophication , 2009, Science.

[17]  N. Stamp.  Out Of The Quagmire Of Plant Defense Hypotheses , 2003, The Quarterly Review of Biology.

[18]  T. Mitchell-Olds,et al.  COST OF DEFENSE IN THE CONTEXT OF PLANT COMPETITION: BRASSICA RAPA MAY GROW AND DEFEND , 2002 .

[19]  Joseph M. Craine,et al.  Reconciling plant strategy theories of Grime and Tilman , 2005 .

[20]  James P. Grover,et al.  The interaction between predation and competition: a review and synthesis , 2002 .

[21]  S. Sakai,et al.  Optimal defense strategy against herbivory in plants: conditions selecting for induced defense, constitutive defense, and no-defense. , 2009, Journal of theoretical biology.

[22]  William Hamilton,et al.  Jasmonate-Induced Responses of Nicotiana sylvestris Results in Fitness Costs Due to Impaired Competitive Ability for Nitrogen , 2000, Journal of Chemical Ecology.

[23]  J. P. Grime,et al.  Evidence for the Existence of Three Primary Strategies in Plants and Its Relevance to Ecological and Evolutionary Theory , 1977, The American Naturalist.

[24]  J. Rosenthal,et al.  Tolerating herbivory: does the plant care if the herbivore has a backbone? , 2000, Evolutionary Ecology.

[25]  F. Chapin,et al.  A safe operating space for humanity , 2009, Nature.

[26]  S. Meiners,et al.  Native and exotic plant species exhibit similar population dynamics during succession. , 2007, Ecology.

[27]  A. Agrawal,et al.  References and Notes Supporting Online Material Evolutionary Trade-offs in Plants Mediate the Strength of Trophic Cascades , 2022 .

[28]  D. Tilman.  Resource competition and community structure. , 1983, Monographs in population biology.

[29]  Helmut Hillebrand,et al.  Nutrient co-limitation of primary producer communities. , 2011, Ecology letters.

[30]  J. Sullivan,et al.  THE IMPACT OF HERBIVORY ON PLANTS IN DIFFERENT RESOURCE CONDITIONS: A META-ANALYSIS , 2001 .

[31]  William G. Lee,et al.  Absence of mammals and the evolution of New Zealand grasses , 2011, Proceedings of the Royal Society B: Biological Sciences.

[32]  E. Welk,et al.  Plant traits affecting herbivory on tree recruits in highly diverse subtropical forests. , 2012, Ecology letters.

[33]  F. Stuart Chapin,et al.  Resource Availability and Plant Antiherbivore Defense , 1985, Science.

[34]  D. Tilman.  Resource competition and plant traits: a response to Craine et al. 2005 , 2007 .

[35]  Mark Fishbein,et al.  Plant defense syndromes. , 2006, Ecology.

[36]  M. Crawley,et al.  Contrasting effects of insect and molluscan herbivores on plant diversity in a long-term field experiment. , 2011, Ecology letters.

[37]  Joy Bergelson,et al.  Surveying Patterns in the Cost of Resistance in Plants , 1996, The American Naturalist.

[38]  J. Terborgh,et al.  Enemies Maintain Hyperdiverse Tropical Forests , 2012, The American Naturalist.

[39]  J. Vivanco,et al.  NO EVIDENCE FOR TRADE‐OFFS: CENTAUREA PLANTS FROM AMERICA ARE BETTER COMPETITORS AND DEFENDERS , 2008 .

[40]  Peter B Adler,et al.  Productivity Is a Poor Predictor of Plant Species Richness , 2011, Science.

[41]  D. Herms,et al.  The Dilemma of Plants: To Grow or Defend , 1992, The Quarterly Review of Biology.

[42]  D. Tilman.  Competition and Biodiversity in Spatially Structured Habitats , 1994 .

[43]  Sean C. Thomas,et al.  The worldwide leaf economics spectrum , 2004, Nature.

[44]  Rebecca E. Irwin,et al.  Direct and ecological costs of resistance to herbivory , 2002 .

[45]  Jonathan M. Chase,et al.  Trade‐offs in community ecology: linking spatial scales and species coexistence , 2004 .

[46]  M. Wise,et al.  Beyond the compensatory continuum: environmental resource levels and plant tolerance of herbivory , 2005 .

[47]  J. P. Grime.  Plant strategy theories: a comment on Craine (2005) , 2007 .

[48]  P. A. Van Zandt.  Plant defense, growth, and habitat: a comparative assessment of constitutive and induced resistance. , 2007, Ecology.

[49]  D. Tilman.  Constraints and tradeoffs: toward a predictive theory of competition and succession , 1990 .

[50]  J. L. Parra,et al.  Very high resolution interpolated climate surfaces for global land areas , 2005 .