| Registro completo |
| Provedor de dados: |
Acta Botanica
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| País: |
Brazil
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| Título: |
Pollen has higher water content when dispersed in a tricellular state than in a bicellular state
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| Autores: |
Williams,Joseph H.
Brown,Chandler D.
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| Data: |
2018-09-01
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| Ano: |
2018
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| Palavras-chave: |
Desiccation stress
Evolution of development
Pollen dispersal
Pollen germination
Pollen hydration
Spore dormancy
Trade-off
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| Resumo: |
ABSTRACT Pollen is generally dispersed in a sexually immature and somewhat dehydrated, metabolically quiescent state. Yet, in some species, pollen at anthesis is well-hydrated and metabolically active, and in 30 % of angiosperms pollen is dispersed after having formed its sperm cells. Pollen water content and sexual maturity may be correlated, either because both are subject to trade-offs between dispersal viability and post-pollination performance, or because the traits display developmental linkages. We inferred relative water content of sexually immature (“bicellular”) and sexually mature (“tricellular”) pollen of 30 species of angiosperms using a hydration index (HI) that ranges from zero to one, based on how near fresh pollen volume is to its minimal (dehydrated) or maximal (hydrated) volume. Tricellular pollen had 30 % higher HI than bicellular pollen (P < 0.005), after controlling for initial pollen size (larger pollen had higher HI; P < 0.05). A literature survey of 344 species indicated that the tricellular and hydrated states were strongly associated, although all four trait state combinations were present (P < 0.0001). Our results suggest that a common mechanism for the repeated origins of tricellular pollen has been via the loss of controlled pollen dehydration, which enables either accelerated or extended pollen development.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062018000300454
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| Editor: |
Sociedade Botânica do Brasil
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| Relação: |
10.1590/0102-33062018abb0129
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| Formato: |
text/html
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| Fonte: |
Acta Botanica Brasilica v.32 n.3 2018
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| Direitos: |
info:eu-repo/semantics/openAccess
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