1
|
Phillips RD, Bohman B, Peakall R. Pollination by nectar-foraging pompilid wasps: a new specialized pollination strategy for the Australian flora. PLANT BIOLOGY (STUTTGART, GERMANY) 2021; 23:702-710. [PMID: 33998761 DOI: 10.1111/plb.13286] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 04/15/2021] [Indexed: 06/12/2023]
Abstract
The Pompilidae is a cosmopolitan and diverse group of wasps, which commonly feed on nectar. However, pollination systems specialized on pompilids have not been documented in detail outside of southern Africa. Here, we studied Caladenia drummondii (Orchidaceae) where, based on floral traits and preliminary field observations, we predicted pollination by sexual deception of male pompilid wasps. Detailed pollinator observations were undertaken using floral baiting experiments at sites spanning 375 km. Following evidence for nectar on some flowers of C. drummondii, the sugar content on the labellum was analysed by GC-MS. Floral spectral reflectance was measured and compared with Caladenia using other pollination strategies. Males of a single species of pompilid wasp (Calopompilus sp.) were the only visitors capable of pollinating C. drummondii. Attempts to feed from the surface of the labellum were frequent and were associated with removal and deposition of pollinia. GC-MS analysis revealed larger quantities of sugar on the labellum than reported in other Caladenia species. While no sexual or courtship behaviour was observed, the zig-zag and circling flight on approach to the flower is suggestive of odour-based attraction. Floral spectral reflectance was similar to sexually deceptive Caladenia. This study represents the first confirmation of a specialized pompilid pollination system outside of Africa. Although pollination occurs during nectar-foraging, long-distance sexual attraction cannot be ruled out as an explanation for the exclusive male visitation. The similarity in floral spectral reflectance to other Caladenia indicates colour may not impose a constraint on the evolution of pollination by pompilids.
Collapse
Affiliation(s)
- R D Phillips
- Department of Ecology, Environment & Evolution, La Trobe University, Bundoora, VIC, Australia
- Department of Biodiversity Conservation and Attractions, Kings Park Science, Kings Park, WA, Australia
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - B Bohman
- Department of Plant Protection Biology, Swedish University of Agricultural Science, Alnarp, Sweden
- School of Molecular Sciences, The University of Western Australia, Crawley, WA, Australia
| | - R Peakall
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| |
Collapse
|
2
|
Oktalira FT, May TW, Dearnaley JDW, Linde CC. Seven new Serendipita species associated with Australian terrestrial orchids. Mycologia 2021; 113:968-987. [PMID: 34338610 DOI: 10.1080/00275514.2021.1919848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Serendipita is one of the main fungal genera that form mutualistic associations with species of orchids (Orchidaceae). Here, seven new Serendipita species associated with various Australian orchid genera are described. These Serendipita species were originally characterized by multilocus DNA sequence species delimitation analyses (three mtDNA and four nuclear genes) and confirmed as distinct with addition of further isolates and reanalysis of nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and nuc 28S rDNA (28S). Culture morphology and microscopic features are presented for each species, three of which are binucleate and four multinucleate. For the ITS region, the seven species have within-species sequence divergence between 1.07% and 4.31%, and all but one of the species pairs is separated by interspecific divergence of at least 4.35%. The newly described Serendipita species, S. australiana, S. communis, S. occidentalis, S. rarihospitum, S. secunda, S. talbotii, and S. warcupii, are shown to be separate species from S. vermifera on the basis of comparison against a sequence from the type. Isolates originally identified by Warcup as Sebacina "vermifera" from Caladenia orchids are revised and shown to belong to three of the species newly described here. Some non-Caladenia isolates identified by Warcup as S. "vermifera" are also shown to be non-conspecific with the type of S. vermifera. On the basis of ITS sequences, 346 isolates from 26 other studies, previously identified under provisional designations, are accommodated under the novel species. The species of Serendipta described here associate with the Australian orchid genera Caladenia, Cyanicula, Elythranthera, Ericksonella, Eriochilus, Glossodia, and Pheladenia. Most of the novel Serendipita species occur widely across Australia, often with widely distributed hosts, but one species, Serendipita rarihospitum, associates with narrowly distributed orchid species.
Collapse
Affiliation(s)
- Fitria T Oktalira
- Ecology and Evolution, Research School of Biology, College of Science, The Australian National University, Canberra, ACT 2601, Australia
| | - Tom W May
- Royal Botanic Gardens Victoria, Birdwood Avenue, Melbourne, VIC 3004, Australia
| | - John D W Dearnaley
- Centre for Crop Health, The University of Southern Queensland, Toowoomba, Queensland 4350, Australia
| | - Celeste C Linde
- Ecology and Evolution, Research School of Biology, College of Science, The Australian National University, Canberra, ACT 2601, Australia
| |
Collapse
|
3
|
Peakall R, Wong DCJ, Phillips RD, Ruibal M, Eyles R, Rodriguez-Delgado C, Linde CC. A multitiered sequence capture strategy spanning broad evolutionary scales: Application for phylogenetic and phylogeographic studies of orchids. Mol Ecol Resour 2021; 21:1118-1140. [PMID: 33453072 DOI: 10.1111/1755-0998.13327] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/22/2020] [Accepted: 01/05/2021] [Indexed: 11/30/2022]
Abstract
With over 25,000 species, the drivers of diversity in the Orchidaceae remain to be fully understood. Here, we outline a multitiered sequence capture strategy aimed at capturing hundreds of loci to enable phylogenetic resolution from subtribe to subspecific levels in orchids of the tribe Diurideae. For the probe design, we mined subsets of 18 transcriptomes, to give five target sequence sets aimed at the tribe (Sets 1 & 2), subtribe (Set 3), and within subtribe levels (Sets 4 & 5). Analysis included alternative de novo and reference-guided assembly, before target sequence extraction, annotation and alignment, and application of a homology-aware k-mer block phylogenomic approach, prior to maximum likelihood and coalescence-based phylogenetic inference. Our evaluation considered 87 taxa in two test data sets: 67 samples spanning the tribe, and 72 samples involving 24 closely related Caladenia species. The tiered design achieved high target loci recovery (>89%), with the median number of recovered loci in Sets 1-5 as follows: 212, 219, 816, 1024, and 1009, respectively. Interestingly, as a first test of the homologous k-mer approach for targeted sequence capture data, our study revealed its potential for enabling robust phylogenetic species tree inferences. Specifically, we found matching, and in one case improved phylogenetic resolution within species complexes, compared to conventional phylogenetic analysis involving target gene extraction. Our findings indicate that a customized multitiered sequence capture strategy, in combination with promising yet underutilized phylogenomic approaches, will be effective for groups where interspecific divergence is recent, but information on deeper phylogenetic relationships is also required.
Collapse
Affiliation(s)
- Rod Peakall
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Darren C J Wong
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Ryan D Phillips
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia.,Department of Ecology, Environment and Evolution, La Trobe University, Melbourne, Vic., Australia
| | - Monica Ruibal
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Rodney Eyles
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Claudia Rodriguez-Delgado
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Celeste C Linde
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| |
Collapse
|
4
|
Basist G, Dyer AG, Garcia JE, Raleigh RE, Lawrie AC. Why Variation in Flower Color May Help Reproductive Success in the Endangered Australian Orchid Caladenia fulva. FRONTIERS IN PLANT SCIENCE 2021; 12:599874. [PMID: 33633758 PMCID: PMC7899986 DOI: 10.3389/fpls.2021.599874] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/15/2021] [Indexed: 05/27/2023]
Abstract
Caladenia fulva G.W. Carr (Tawny Spider-orchid) is a terrestrial Australian endangered orchid confined to contiguous reserves in open woodland in Victoria, Australia. Natural recruitment is poor and no confirmed pollinator has been observed in the last 30 years. Polymorphic variation in flower color complicates plans for artificial pollination, seed collection and ex situ propagation for augmentation or re-introduction. DNA sequencing showed that there was no distinction among color variants in the nuclear ribosomal internal transcribed spacer (ITS) region and the chloroplast trnT-trnF and matK regions. Also, authentic specimens of both C. fulva and Caladenia reticulata from the reserves clustered along with these variants, suggesting free interbreeding. Artificial cross-pollination in situ and assessment of seed viability further suggested that no fertility barriers existed among color variants. Natural fruit set was 15% of the population and was proportional to numbers of the different flower colors but varied with orchid patch within the population. Color modeling on spectral data suggested that a hymenopteran pollinator could discriminate visually among color variants. The similarity in fruiting success, however, suggests that flower color polymorphism may avoid pollinator habituation to specific non-rewarding flower colors. The retention of large brightly colored flowers suggests that C. fulva has maintained attractiveness to foraging insects rather than evolving to match a scarce unreliable hymenopteran sexual pollinator. These results suggest that C. fulva should be recognized as encompassing plants with these multiple flower colors, and artificial pollination should use all variants to conserve the biodiversity of the extant population.
Collapse
Affiliation(s)
- Georgia Basist
- School of Science, RMIT University, Bundoora, VIC, Australia
| | - Adrian G. Dyer
- Bio-inspired Digital Sensing Lab, School of Media and Communication, RMIT University, Melbourne, VIC, Australia
- Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Jair E. Garcia
- Bio-inspired Digital Sensing Lab, School of Media and Communication, RMIT University, Melbourne, VIC, Australia
| | - Ruth E. Raleigh
- School of Science, RMIT University, Bundoora, VIC, Australia
- Royal Botanic Gardens Melbourne, South Yarra, VIC, Australia
| | - Ann C. Lawrie
- School of Science, RMIT University, Bundoora, VIC, Australia
| |
Collapse
|
5
|
Arifin AR, May TW, Linde CC. New species of Tulasnella associated with Australian terrestrial orchids in the Cryptostylidinae and Drakaeinae. Mycologia 2020; 113:212-230. [PMID: 33146586 DOI: 10.1080/00275514.2020.1813473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Many orchids have an obligate relationship with Tulasnella mycorrhizal fungi for seed germination and support into adulthood. Despite the importance of Tulasnella as mycorrhizal partners, many species remain undescribed. Here, we use multiple sequence locus phylogenetic analyses to delimit and describe six new Tulasnella species associated with Australian terrestrial orchids from the subtribes Cryptostylidinae and Drakaeinae. Five of the new species, Tulasnella australiensis, T. occidentalis, T. punctata, T. densa, and T. concentrica, all associate with Cryptostylis (Cryptostylidinae), whereas T. rosea associates with Spiculaea ciliata (Drakaeinae). Isolates representing T. australiensis were previously also reported in association with Arthrochilus (Drakaeinae). All newly described Tulasnella species were delimited by phylogenetic analyses of four loci (nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 [ITS], C14436 [ATP synthase], C4102 [glutamate synthase], and mt 16S rDNA [mtLSU]). The pairwise sequence divergence between species for the ITS region ranged from 5.6% to 25.2%, and the maximum sequence divergence within the newly described species ranged from 1.64% to 4.97%. There was a gap in the distribution of within- and between-species pairwise divergences in the region of 4-6%, with only one within-species value of 4.97% (for two T. australiensis isolates) and one between-species value of 5.6% (involving an isolate of T. occidentalis) falling within this region. Based on fluorescence staining, all six new Tulasnella species are binucleate and have septate, cylindrical hyphae. There was some subtle variation in culture morphology, but colony diameter as measured on 3MN+vitamin medium after 6 wk of growth did not differ among species. However, T. australiensis grew significantly (P < 0.02) slower than others on ½ FIM and ¼ potato dextrose agar (PDA) media. Formal description of these Tulasnella species contributes significantly to documentation of Tulasnella diversity and provides names and delimitations to underpin further research on the fungi and their relationships with orchids.
Collapse
Affiliation(s)
- Arild R Arifin
- Ecology and Evolution, Research School of Biology, The Australian National University , Canberra, ACT 2601, Australia
| | - Tom W May
- Royal Botanic Gardens Victoria, Birdwood Avenue, Melbourne , VIC 3004, Australia
| | - Celeste C Linde
- Ecology and Evolution, Research School of Biology, The Australian National University , Canberra, ACT 2601, Australia
| |
Collapse
|
6
|
Evaluating multilocus Bayesian species delimitation for discovery of cryptic mycorrhizal diversity. FUNGAL ECOL 2017. [DOI: 10.1016/j.funeco.2016.11.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
7
|
Convergent evolution of sexual deception via chromatic and achromatic contrast rather than colour mimicry. Evol Ecol 2016. [DOI: 10.1007/s10682-016-9863-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|