Abstract:
:The biological nature of some symbioses is unclear because it is often not easy to discern whether the symbionts obtain any benefits from the association. Mastodia tessellata, a symbiosis between a leafy green alga and a fungus of uncertain phylogenetic position, is among the most investigated, controversial, and poorly understood associations. Because it has been difficult to determine whether this association is mutually beneficial or parasitic, not all scientists accept M. tessellata as a true lichen symbiosis. Mastodia tessellata is thus an interesting model to illustrate the interactions and processes that occur in fungal-algal symbioses. To improve our understanding of this association, we address the phylogenetic positions of the bionts involved and examine their interactions at the ultrastructural level. Examining the nuLSU and nuSSU gene regions of the mycobiont and the rbcL gene region of the photobiont, we found the fungus to be related to a group of marine species in the genus Verrucaria, family Verrucariaceae, despite its present ascription to the family Mastodiaceae. In addition, the photobiont of the symbiosis emerged as closely related to the North American species Prasiola borealis. Our electron microscopy observations provide new information on the process of fungal colonization of the algal thalli, as well as on relationships between the symbionts during different stages of colonization. The special features of this lichen symbiosis are discussed and compared with other examples of fungal symbioses in nature.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Pérez-Ortega S,Ríos Ade L,Crespo A,Sancho LGdoi
10.3732/ajb.0900323subject
Has Abstractpub_date
2010-05-01 00:00:00pages
738-52issue
5eissn
0002-9122issn
1537-2197pii
ajb.0900323journal_volume
97pub_type
杂志文章abstract::Bennettitales is an extinct group of seed plants with reproductive structures that are similar in some respects to both Gnetales and angiosperms, but systematic relationships among the three clades remain controversial. This study summarizes characters of bennettitalean plants and presents new evidence for the structu...
journal_title:American journal of botany
pub_type: 杂志文章
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2012-11-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2009-08-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.2007342
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更新日期:2007-05-01 00:00:00
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pub_type: 杂志文章
doi:10.3732/ajb.91.10.1582
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400145
更新日期:2014-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800380
更新日期:2009-05-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.4.709
更新日期:2005-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-08-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200359
更新日期:2013-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1000289
更新日期:2011-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/j.1537-2197.1986.tb09673.x
更新日期:1986-01-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1143
更新日期:2018-09-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.8.1197
更新日期:2002-08-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400466
更新日期:2015-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800102
更新日期:2009-06-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100392
更新日期:2012-03-01 00:00:00
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pub_type: 杂志文章
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更新日期:2012-06-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1049
更新日期:2018-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.9.1485
更新日期:2002-09-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600166
更新日期:2016-06-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100040
更新日期:2011-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2000-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500452
更新日期:2016-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:1992-10-01 00:00:00