The adaptive value of cued dispersal in desert plants: seed retention and release in Mammillaria pectinifera, a small globose cactus

Serotiny, or delayed seed dispersal, is common in fluctuating environments because it hedges the risks of establishment. Mammillaria pectinifera (Cactaceae) facultatively expels fruits in the year they are produced or retains them to disperse the seed over several years. We tested whether M. pectini...

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Detalhes bibliográficos
Autores: Peters, EM, Martorell-Delgado, Carlos, Ezcurra, E
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:México
Recursos:Universidad Nacional Autónoma de México
Repositorio:Sistema de Información de la Facultad de Ciencias, UNAM
OAI Identifier:oai:repositorio.fciencias.unam.mx:11154/141152
Acesso em linha:http://hdl.handle.net/11154/141152
Access Level:acceso abierto
Palavra-chave:Bet-hedging
Cactaceae
environmental triggers
Mammillaria
Mexico; serotiny
Tehuacán Valley
Descrição
Resumo:Serotiny, or delayed seed dispersal, is common in fluctuating environments because it hedges the risks of establishment. Mammillaria pectinifera (Cactaceae) facultatively expels fruits in the year they are produced or retains them to disperse the seed over several years. We tested whether M. pectinifera increased fruit expulsion as a response to increased rainfall. While no fruit expulsion was observed in 1997, a dry year, in the wetter 1998 around 20% of all fruits formed were expelled from the maternal plant. A greenhouse experiment showed that high moisture results in the plants expelling all their fruits. Because in 1998 establishment was five times higher than in 1997, this response seems to be highly adaptive: Active fruit expulsion and consequent seed release increases the probability of establishment during pulses of high precipitation.