Among-species differences in pollen quality and quantity limitation: implications for endemics in biodiverse hotspots

Insufficient pollination is a function of quantity and quality of pollen receipt, and the relative contribution of each to pollen limitation may vary with intrinsic plant traits and extrinsic ecological properties. Community-level studies are essential to evaluate variation across species in quality...

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Detalles Bibliográficos
Autores: GERARDO ARCEO GOMEZ, VICTOR PROSPERO PARRA TABLA
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:México
Institución:Universidad Autónoma de Yucatán
Repositorio:Repositorio Digital Institucional de la Universidad Autónoma de Yucatán
Idioma:inglés
OAI Identifier:oai:redi.uady.mx:123456789/1490
Acceso en línea:http://redi.uady.mx:8080/handle/123456789/1490
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/cti/2
info:eu-repo/classification/cti/3
Co-flowering community
Mediterranean
Piecewise regression
Pollen limitation
Pollen tubes
Pollination
Stigmatic pollen load
Yucatan
Descripción
Sumario:Insufficient pollination is a function of quantity and quality of pollen receipt, and the relative contribution of each to pollen limitation may vary with intrinsic plant traits and extrinsic ecological properties. Community-level studies are essential to evaluate variation across species in quality limitation under common ecological conditions. This study examined whether endemic species are more limited by pollen quantity or quality than non-endemic co-flowering species in three endemic-rich plant communities located in biodiversity hotspots of different continents (Andalusia, California and Yucatan). Methods: Natural variations in pollen receipt and pollen tube formation were analysed for 20 insect-pollinated plants. Endemic and non-endemic species that co-flowered were paired in order to estimate and compare the quantity and quality components of pre-zygotic pollination success, obtained through piecewise regression analysis of the relationship between pollen grains and pollen tubes of naturally pollinated wilted flowers. Key Results: Pollen tubes did not frequently exceed the number of ovules per flower. Only the combination of abundant and good quality pollen and a low number of ovules per flower conferred relief from pre-zygotic pollen limitation in the three stochastic pollination environments studied. Quality of pollen receipt was found to be as variable as quantity among study species. The relative pollination success of endemic and non-endemic species, and its quantity and quality components, was community dependent. Conclusions: Assessing both quality and quantity of pollen receipt is key to determining the ovule fertilization potential of both endemic and widespread plants in biodiverse hotspot regions. Large natural variation among flowers of the same species in the two components and pollen tube formation deserves further analysis in order to estimate the environmental, phenotypic and intraindividual sources of variation that may affect how plants evolve to overcome this limitation in different communities worldwide.