Plant preferential allocation and fungal reward decline with soil phosphorus: implications for mycorrhizal mutualism

Ecosphere - Tập 7 Số 5 - 2016
Bao‐Ming Ji1, James D. Bever2,3
1College of Forestry, Beijing Forestry University, Beijing 100083, China
2Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
3Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas 66045, USA

Tóm tắt

AbstractExplaining the persistence of mutualism remains a challenge in ecology and evolutionary biology. The evolutionary stability of arbuscular mycorrhiza, a most widespread and ancient mutualistic association, is particularly intriguing because plants lack apparent mechanisms to prevent cheaters from gaining competitive advantages over cooperators. We developed a triple isotopic labeling method (14C, 32P, and 33P) within a split‐root design to measure the exchange of carbon (C) and phosphorus (P) between the host plant and two mycorrhizal partners across a soil P gradient. Host plant preferentially allocated more C to the roots associated with the fungus delivering higher P per unit plant C, and the strength of preferential allocation decreased with increasing soil P availability. The host plant received more P per unit of allocated C from the better fungus and this advantageous exchange rate did not depend upon P availability. As a result, the level of preferential allocation was correlated with the differential delivery of P from the two fungi. Our findings suggest that plant preferential allocation to better mutualists can stabilize mutualisms in environments limiting in the traded resource, but as the availability of this resource increases, plant preferential allocation declines. This environmental dependence of preferential allocation generates predictions of declining levels in relative abundance of mutualistic fungi in high‐resource environments.

Từ khóa


Tài liệu tham khảo

10.1007/s00442-009-1345-6

10.1098/rspb.2002.2162

10.1111/nph.13239

10.2307/2261701

10.1111/j.1461-0248.2008.01254.x

10.1002/j.1537-2197.1990.tb13579.x

10.1668/0003-1569(2001)041[0825:TCOM]2.0.CO;2

10.1890/0012-9658(2003)084[0323:IAFVCT]2.0.CO;2

10.1111/j.1469-8137.2006.01861.x

10.2307/2259639

10.1146/annurev.micro.58.030603.123749

10.1093/biomet/56.3.635

10.1098/rspb.2002.2312

10.1111/j.1461-0248.2009.01430.x

10.1111/j.1469-8137.1992.tb01800.x

Janzen D. H., 1985, The biology of mutualism, 40

10.1890/09-1451.1

10.1111/mec.12268

10.2307/1942106

10.1111/j.1469-8137.2009.03110.x

10.1046/j.1469-8137.1997.00729.x

10.1073/pnas.0906710107

10.1139/b04-110

10.1126/science.1208473

10.1007/BF02181750

10.1046/j.1469-8137.2002.00429.x

10.1111/j.1469-8137.1993.tb03840.x

10.1126/science.289.5486.1920

10.1111/jipb.12155

Smith S. E., 2008, Mycorrhizal symbiosis

10.1046/j.1469-8137.2000.00695.x

10.1104/pp.103.024380

10.2136/sssaj1972.03615995003600060020x

10.2307/3793102

10.1111/j.1752-4571.2010.00145.x

10.1080/00103628709367806

10.1111/nph.13025

Thông tin
Thông tin xuất bản

Ecosphere

Tập 7 Số 5

Thông tin tác giả