Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa
Potential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40,...
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PeerJ Inc.
2015-06-01
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| author | Edison A. Díaz-Álvarez Roberto Lindig-Cisneros Erick de la Barrera |
| author_facet | Edison A. Díaz-Álvarez Roberto Lindig-Cisneros Erick de la Barrera |
| author_sort | Edison A. Díaz-Álvarez |
| collection | DOAJ |
| description | Potential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40, and 80 kg N ha−1 yr−1) in order to assess the potential risk facing this orchid given impending scenarios of nitrogen deposition. Lower doses of nitrogen of up to 20 kg N ha yr−1, the dose that led to optimal plant performance, acted as fertilizer. For instance, the production of leaves and pseudobulbs were respectively 35% and 36% greater for plants receiving 20 kg N ha yr−1 than under any other dose. Also, the chlorophyll content and quantum yield peaked at 0.66 ± 0.03 g m−2 and 0.85 ± 0.01, respectively, for plants growing under the optimum dose. In contrast, toxic effects were observed at the higher doses of 40 and 80 kg N ha yr−1. The δ13C for leaves averaged −14.7 ± 0.2‰ regardless of the nitrogen dose. In turn, δ15N decreased as the nitrogen dose increased from 0.9 ± 0.1‰ under 2.5 kg N ha−1yr−1 to −3.1 ± 0.2‰ under 80 kg N ha−1yr−1, indicating that orchids preferentially assimilate NH4+ rather than NO3− of the solution under higher doses of nitrogen. Laelia speciosa showed a clear response to inputs of nitrogen, thus, increasing rates of atmospheric nitrogen deposition can pose an important threat for this species. |
| first_indexed | 2024-03-09T06:30:17Z |
| format | Article |
| id | doaj.art-b08891753d124e298701149214ea2018 |
| institution | Directory Open Access Journal |
| issn | 2167-8359 |
| language | English |
| last_indexed | 2024-03-09T06:30:17Z |
| publishDate | 2015-06-01 |
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| spelling | doaj.art-b08891753d124e298701149214ea20182023-12-03T11:07:00ZengPeerJ Inc.PeerJ2167-83592015-06-013e102110.7717/peerj.10211021Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosaEdison A. Díaz-Álvarez0Roberto Lindig-Cisneros1Erick de la Barrera2Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, Distrito Federal, MexicoInstituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, MexicoInstituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, MexicoPotential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40, and 80 kg N ha−1 yr−1) in order to assess the potential risk facing this orchid given impending scenarios of nitrogen deposition. Lower doses of nitrogen of up to 20 kg N ha yr−1, the dose that led to optimal plant performance, acted as fertilizer. For instance, the production of leaves and pseudobulbs were respectively 35% and 36% greater for plants receiving 20 kg N ha yr−1 than under any other dose. Also, the chlorophyll content and quantum yield peaked at 0.66 ± 0.03 g m−2 and 0.85 ± 0.01, respectively, for plants growing under the optimum dose. In contrast, toxic effects were observed at the higher doses of 40 and 80 kg N ha yr−1. The δ13C for leaves averaged −14.7 ± 0.2‰ regardless of the nitrogen dose. In turn, δ15N decreased as the nitrogen dose increased from 0.9 ± 0.1‰ under 2.5 kg N ha−1yr−1 to −3.1 ± 0.2‰ under 80 kg N ha−1yr−1, indicating that orchids preferentially assimilate NH4+ rather than NO3− of the solution under higher doses of nitrogen. Laelia speciosa showed a clear response to inputs of nitrogen, thus, increasing rates of atmospheric nitrogen deposition can pose an important threat for this species.https://peerj.com/articles/1021.pdfAcid rainBiodiversity lossCAMConservation physiologyδ15NNitrogen pollution |
| spellingShingle | Edison A. Díaz-Álvarez Roberto Lindig-Cisneros Erick de la Barrera Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa PeerJ Acid rain Biodiversity loss CAM Conservation physiology δ15N Nitrogen pollution |
| title | Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa |
| title_full | Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa |
| title_fullStr | Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa |
| title_full_unstemmed | Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa |
| title_short | Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa |
| title_sort | responses to simulated nitrogen deposition by the neotropical epiphytic orchid laelia speciosa |
| topic | Acid rain Biodiversity loss CAM Conservation physiology δ15N Nitrogen pollution |
| url | https://peerj.com/articles/1021.pdf |
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