Carbon and nitrogen gain during the growth of orchid seedlings in nature. Issue 2 (21st January 2014)

• Record Type: Journal Article
• Authors: Stöckel, Marcus; Těšitelová, Tamara; Jersáková, Jana; Bidartondo, Martin I.; Gebauer, Gerhard
• Is Part Of: New phytologist. Volume 202:Issue 2(2014)
• Page Start: 606
• Page End: 615
• Publication Date: 2014-01-21
• Subjects: Botany -- Periodicals; 580
• DOI: 10.1111/nph.12688
• Languages: English
• ISSNs: 0028-646X

Abstract

<abstract abstract-type="main" id="nph12688-abs-0001"> <title>Summary</title> <p> <list id="nph12688-list-0001" list-type="bullet"> <list-item> <p>For germination and establishment, orchids depend on carbon (C) and nutrients supplied by mycorrhizal fungi. As adults, the majority of orchids then appear to become autotrophic. To compare the proportional C and nitrogen (N) gain from fungi in mycoheterotrophic seedlings and in adults, here we examined in the field C and N stable isotope compositions in seedlings and adults of orchids associated with ectomycorrhizal and saprotrophic fungi.</p> </list-item> <list-item> <p>Using a new highly sensitive approach, we measured the isotope compositions of seedlings and adults of four orchid species belonging to different functional groups: fully and partially mycoheterotrophic orchids associated with narrow or broad sets of ectomycorrhizal fungi, and two adult putatively autotrophic orchids associated exclusively with saprotrophic fungi.</p> </list-item> <list-item> <p>Seedlings of orchids associated with ectomycorrhizal fungi were enriched in <sup>13</sup>C and <sup>15</sup>N similarly to fully mycoheterotrophic adults. Seedlings of saprotroph‐associated orchids were also enriched in <sup>13</sup>C and <sup>15</sup>N, but unexpectedly their enrichment was significantly lower, making them hardly distinguishable from their respective adult stages and neighbouring autotrophic plants.</p> </list-item> <list-item> <p>We conclude that partial mycoheterotrophy among saprotroph‐associated orchids cannot be identified unequivocally based on C and N isotope compositions alone. Thus, partial mycoheterotrophy may be much more widely distributed among orchids than hitherto assumed.</p> </list-item> </list> </p> </abstract>