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Worthy FR, Schaefer DA, Wanasinghe D, Xu JC, Wang LS, Wang XY. Acquisition of green algal photobionts enables both chlorolichens and chloro-cyanolichens to activate photosynthesis at low humidity without liquid water. AOB PLANTS 2024; 16:plae025. [PMID: 38770101 PMCID: PMC11102867 DOI: 10.1093/aobpla/plae025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Accepted: 04/23/2024] [Indexed: 05/22/2024]
Abstract
Cyanobacteria require liquid water for photosynthesis, whereas green algae can photosynthesise with water vapour alone. We discovered that several Lobaria spp. which normally have cyanobacteria as the sole photobiont, in some regions of the trans-Himalayas also harboured green algae. We tested whether green algal acquisition was: limited to high elevations; obtained from neighbouring chloro-Lobaria species; enabled photosynthesis at low humidity. Lobaria spp. were collected from 2000 to 4000 m elevation. Spectrophotometry quantified green algal abundance by measuring chlorophyll b (absent in cyanobacteria). Thalli cross-sections visually confirmed green algal presence. We sequenced gene regions: Lobaria (ITS-EF-1α-RPB2), green algae (18S-RBC-L) and Nostoc (16S). Phylogenetic analysis determined myco-photobiont associations. We used a custom closed-circuit gas exchange system with an infrared gas analyser to measure CO2 exchange rates for desiccated specimens at 33%, 76%, 86% and 98% humidity. Cross-sections revealed that the photobiont layers in putative cyano-Lobaria contained both cyanobacteria and green algae, indicating that they should be considered chloro-cyanolichens. Chloro-Lobaria had no visible cephalodia nor cyanobacteria in the photobiont layer. Chloro-Lobaria and chloro-cyano-Lobaria had comparable levels of chlorophyll b. Chloro-Lobaria usually contained Symbiochloris. Chloro-cyano-Lobaria mainly associated with Parachloroidium and Nostoc; infrequently with Symbiochloris, Apatococcus, Chloroidium, Pseudochlorella, Trebouxia. Sequences from two green algal genera were obtained from within some thalli. Desiccated specimens of every Lobaria species could attain net photosynthesis with light exposure and 33% humidity. CO2 exchange dynamics over a five-day period differed between species. At all elevations, chloro-cyano-Lobaria spp. had abundant green algae in the photobiont layer, but green algal strains mostly differed to those of chloro-Lobaria spp. Both chloro-Lobaria and chloro-cyano-Lobaria were capable of conducting photosynthesis without liquid water. The data strongly suggest that they attained positive net photosynthesis.
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Affiliation(s)
- Fiona Ruth Worthy
- Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Douglas Allen Schaefer
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Dhanushka Wanasinghe
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Department of Soil Science, College of Food and Agriculture Sciences, King Saud University, Riyadh 11362, Saudi Arabia
| | - Jian Chu Xu
- Honghe Centre for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Li Song Wang
- Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
| | - Xin Yu Wang
- Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, Yunnan 650201, China
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Yang M, Werth S, Wang L, Scheidegger C. Phylogeographic analyses of an epiphytic foliose lichen show multiple dispersal events westward from the Hengduan Mountains of Yunnan into the Himalayas. Ecol Evol 2022; 12:e9308. [PMID: 36177127 PMCID: PMC9475131 DOI: 10.1002/ece3.9308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 08/24/2022] [Accepted: 08/26/2022] [Indexed: 11/09/2022] Open
Abstract
Lobaria pindarensis is an endemic species of the Himalayas and the Hengduan Mountains. Little information is available on the phylogeography genetics and colonization history of this species or how its distribution patterns changed in response to the orographic history of the Himalayas and Hengduan Mountains. Based on samples covering a major part of the species' distribution range, we used 443 newly generated sequences of nine loci for molecular coalescent analyses in order to reconstruct the evolutionary history of L. pindarensis, and to reconstruct the species' ancestral phylogeographic distributions using Bayesian binary MCMC analyses. The results suggest that current populations originated from the Yunnan region of the Hengduan Mountains in the middle Pliocene, and that the Himalayas of Bhutan were colonized by a lineage that diverged from Yunnan ca. 2.72 Ma. The analysis additionally indicates that the Nepal and Xizang areas of the Himalayas were colonized from Yunnan as well, and that there was later a second dispersal event from Yunnan to Bhutan. We conclude that the change in climate and habitat related to the continuous uplift of the Himalayas and the Hengduan Mountains in the late Pliocene and middle Pleistocene influenced the geographic distribution pattern of L. pindarensis.
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Affiliation(s)
- Mei‐Xia Yang
- Biodiversity and Conservation BiologySwiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
- Institute of Plant SciencesUniversity of BernBernSwitzerland
- Division of Life Science and Center for Chinese MedicineThe Hong Kong University of Science and TechnologyHong KongChina
| | - Silke Werth
- Systematics, Biodiversity and Evolution of Plants, Ludwig Maximilian University MunichMunichGermany
| | - Li‐Song Wang
- Key Laboratory for Plant Diversity and Biogeography of East AsiaKunming Institute of Botany, Chinese Academy of SciencesKunmingChina
| | - Christoph Scheidegger
- Biodiversity and Conservation BiologySwiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorfSwitzerland
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