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An evolutionary view - vegetative desiccation tolerance in plants |
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| Order/ |
Tolerance characteristics |
Developmental complexity |
Mechanisms of tolerance |
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| Liverworts/ |
Rapid desiccation tolerated; |
Anatomically primitive |
Cell integrity maintained during drying |
| hornworts/ |
Some protection mechanisms |
No vasculature |
Rehydration leads to damage |
| mosses |
focus on repair mechanisms |
Rapid recovery |
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| photosynthetic-apparatus maintained |
Presence of non-reducing sugars, dehydrins and |
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| rehydrins appear |
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| Pre-stress existence of mRNA in RNPs |
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| Selaginellales, |
Slower desiccation required; |
Vascular tissues develop |
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| Isoetales, |
photosynthetic-apparatus maintained |
Scarcity of data |
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| Lycopodiales |
Epidermis appears |
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| Equisetum/ |
Slow desiccation required |
Increasing anatomical and |
Scarcity of data |
| Ferns |
developmental complexity |
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| Epidermis appears |
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| Gymnosperms |
No vegetative desiccation |
Beginning seed desiccation |
Scarcity of data |
| tolerance |
tolerance |
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| Angiosperms |
(Re)-discovery of vegetative |
Established seed desiccation |
Transcripts for proteins typical for drying |
| desiccation tolerance |
tolerance |
seeds induced in vegetative tissues |
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| Monocots |
Slow desiccation required |
Transcripts of unknown function homologous |
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| Poaceae |
Focus on protection of |
to constitutively expressed moss genes |
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| Liliaceae |
existing structures |
are induced |
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| Dicots |
Photosynthetic-apparatus either maintained |
LEA proteins, sugars and oligosaccharides, |
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| Hamamelidaceae |
or reduced during desiccation |
Dehydrins and rehydrins in complex gene families |
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| Labiatae |
Tolerance inducible, ABA influence, sugars may be |
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| Gesneriaceae |
present or inducible |
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| Scrophulariaceae |
Transcription factors, vesicular traffic |
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Included are major systematic orders of plants in increasing organizational complexity and following plant appearance during evolution. Monocots - plants with a single cotyledon (for example, grasses [Poaceae]; Sporobolus stapfianus is a desiccation tolerant species in the Poaceae family); dicots - two cotyledons (for example, Arabidopsis thaliana; Craterostigma plantagineum is in this class). Tortula ruralis is, among the mosses, the best studied desiccation tolerant species. ABA, abscisic acid; LEA, late embryogenesis abundant. | |||
Bohnert Genome Biology 2000 1:reviews1010.1 doi:10.1186/gb-2000-1-2-reviews1010 |
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