Selenium accumulation in flowers and its effects on pollination.

Autor: Quinn CF; Department of Biology, Colorado State University, Fort Collins, CO 80532, USA., Prins CN, Freeman JL, Gross AM, Hantzis LJ, Reynolds RJ, Yang Si, Covey PA, Bañuelos GS, Pickering IJ, Fakra SC, Marcus MA, Arathi HS, Pilon-Smits EA
Jazyk: angličtina
Zdroj: The New phytologist [New Phytol] 2011 Nov; Vol. 192 (3), pp. 727-37. Date of Electronic Publication: 2011 Jul 27.
DOI: 10.1111/j.1469-8137.2011.03832.x
Abstrakt: • Selenium (Se) hyperaccumulation has a profound effect on plant-arthropod interactions. Here, we investigated floral Se distribution and speciation in flowers and the effects of floral Se on pollen quality and plant-pollinator interactions. • Floral Se distribution and speciation were compared in Stanleya pinnata, an Se hyperaccumulator, and Brassica juncea, a comparable nonhyperaccumulator. Pollen germination was measured from plants grown with varying concentrations of Se and floral visitation was compared between plants with high and low Se. • Stanleya pinnata preferentially allocated Se to flowers, as nontoxic methyl-selenocysteine (MeSeCys). Brassica juncea had higher Se concentrations in leaves than flowers, and a lower fraction of MeSeCys. For B. juncea, high floral Se concentration impaired pollen germination; in S. pinnata Se had no effect on pollen germination. Floral visitors collected from Se-rich S. pinnata contained up to 270 μg g(-1), concentrations toxic to many herbivores. Indeed, floral visitors showed no visitation preference between high- and low-Se plants. Honey from seleniferous areas contained 0.4-1 μg Se g(-1), concentrations that could provide human health benefits. • This study is the first to shed light on the possible evolutionary cost, through decreased pollen germination in B. juncea, of Se accumulation and has implications for the management of seleniferous areas.
(© 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.)
Databáze: MEDLINE
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