Title data
Zahn, Franziska E. ; Jiang, Hong ; Lee, Yung-I ; Gebauer, Gerhard:
Mode of carbon gain and fungal associations of Neuwiedia malipoensis within
the evolutionarily early-diverging orchid subfamily Apostasioideae.
In: Annals of Botany.
Vol. 134
(2024)
Issue 3
.
- pp. 511-520.
ISSN 1095-8290
DOI: https://doi.org/10.1093/aob/mcae097
Abstract in another language
• Background and Aims
The earliest-diverging orchid lineage, Apostasioideae, consists only of two genera: Apostasia and Neuwiedia. Previous reports of Apostasia nipponica indicated a symbiotic association with an ectomycorrhiza-forming Ceratobasidiaceae clade and partial utilization of fungal carbon during the adult stage. However, the trophic strategy of Neuwiedia throughout its development remains unidentified. To further improve our understanding of mycoheterotrophy in the Apostasioideae, this study focused on Neuwiedia malipoensis examining both the mycorrhizal association and the physiological ecology of this orchid species across various development stages.
• Methods
We identified the major mycorrhizal fungi of N. malipoensis protocorm, leafy seedling and adult stages using molecular barcoding. To reveal nutritional resources utilized by N. malipoensis, we compared stable isotope natural abundances (δ13C, δ15N, δ2H, δ18O) of different developmental stages with those of autotrophic reference plants.
• Key Results
Protocorms exhibited an association with saprotrophic Ceratobasidiaceae rather than ectomycorrhiza-forming Ceratobasidiaceae and the 13C signature was characteristic of their fully mycoheterotrophic nutrition. Seedlings and adults were predominantly associated with saprotrophic fungi belonging to the Tulasnellaceae. While 13C and 2H stable isotope data revealed partial mycoheterotrophy of seedlings, it is unclear to what extent the fungal carbon supply is reduced in adult N. malipoensis. However, the 15N enrichment of mature N. malipoensis suggests partially mycoheterotrophic nutrition. Our data indicated a transition in mycorrhizal partners during ontogenetic development with decreasing dependency of N. malipoensis on fungal nitrogen and carbon.
• Conclusions
The divergence in mycorrhizal partners between N. malipoensis and A. nipponica indicates different resource acquisition strategies and allows various habitat options in the earliest-diverging orchid lineage, Apostasioideae. While A. nipponica relies on the heterotrophic carbon gain from its ectomycorrhizal fungal partner and thus on forest habitats, N. malipoensis rather relies on own photosynthetic carbon gain as an adult, allowing it to establish in habitats as widely distributed as those where Rhizoctonia fungi occur.
Further data
Item Type: | Article in a journal |
---|---|
Refereed: | Yes |
Keywords: | Mycoheterotrophy; mycorrhiza; Orchidaceae; Apostasioideae; Neuwiedia; stable isotopes; carbon; nitrogen; hydrogen; Ceratobasidiaceae; Tulasnellaceae |
Institutions of the University: | Profile Fields Profile Fields > Advanced Fields Profile Fields > Advanced Fields > Ecology and the Environmental Sciences |
Result of work at the UBT: | Yes |
DDC Subjects: | 500 Science 500 Science > 580 Plants (Botany) |
Date Deposited: | 24 Sep 2024 05:23 |
Last Modified: | 24 Sep 2024 05:23 |
URI: | https://eref.uni-bayreuth.de/id/eprint/90476 |