Phosphorus facilitation and covariation of root traits in steppe species

• Published in: The New phytologist Vol. 226; no. 5; pp. 1285 - 1298
• Main Authors: Yu, Rui-Peng, Li, Xiao-Xi, Xiao, Zhi-Hua, Lambers, Hans, Li, Long
• Format: Journal Article
• Language: English
• Published: England Wiley 01.06.2020; Wiley Subscription Services, Inc
• Subjects: Acid phosphatase; Bromus inermis; Coexistence; Complementarity; diversity effect; enzyme activity; Greenhouses; Interspecific; interspecific phosphorus facilitation; Kengia squarrosa; Phenotype; Phosphatase; Phosphorus; phosphorus‐impoverished soil; phosphorus‐mobilizing species; Plant Roots; Plant species; Plants (botany); plasticity; Poaceae; Proliferation; Rhizosphere; rhizosphere process; roots; Soil; Species; species coexistence; Steppes; diversity effect; interspecific phosphorus facilitation; rhizosphere process; phosphorus-mobilizing species; plasticity; phosphorus-impoverished soil; species coexistence
• ISSN: 0028-646X; 1469-8137; 1469-8137
• DOI: 10.1111/nph.16499

• Different phosphorus (P)-acquisition strategies may be relevant for species coexistence and plant performance in terrestrial communities on P-deficient soils. However, how interspecific P facilitation functions in natural systems is largely unknown. • We investigated the root physiological activities for P mobilization across 19 coexisting plant species in steppe vegetation, and then grew plants with various abilities to mobilize sorbed P in a microcosm in a glasshouse. • We show that P facilitation mediated by rhizosphere processes of P-mobilizing species promoted growth and increased P content of neighbors in a species-specific manner. When roots interacted with a facilitating neighbor, Cleistogenes squarrosa and Bromus inermis tended to show greater plasticity of root proliferation or rhizosheath acid phosphatase activity compared with other non-P-mobilizing species. Greater variation in these root traits was strongly correlated with increased performance in the presence of a facilitator. The results also show, for the first time, that P facilitation was an important mechanism underlying a positive complementarity effect. • Our study highlights that interspecific P-acquisition facilitation requires that facilitated neighbors exhibit a better match of root traits with a facilitating species. It provides a better understanding of species coexistence in P-limited communities.