Title: | Physical dormancy in seeds: a game of hide and seek? |
Author(s): | Paulsen TR; Colville L; Kranner I; Daws MI; Hogstedt G; Vandvik V; Thompson K; |
Address: | "Department of Biology, University of Bergen, Postboks 7803, 5020, Bergen, Norway. Department of Molecular Biology, University of Bergen, Postboks 7803, 5020, Bergen, Norway. Seed Conservation Department, Royal Botanic Gardens Kew, Wakehurst Place, Ardingly, West Sussex, RH17 6TN, UK. Institute of Botany, University of Innsbruck, Sternwartestrasse 15, A-6020, Innsbruck, Austria. Alcoa of Australia Limited, PO Box 172, Pinjarra, WA, 6208, Australia. Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK" |
ISSN/ISBN: | 1469-8137 (Electronic) 0028-646X (Linking) |
Abstract: | "Historically, 'physical dormancy', or 'hard seededness', where seeds are prevented from germinating by a water-impermeable seed coat, is viewed as a dormancy mechanism. However, upon water uptake, resumption of metabolism leads to the unavoidable release of volatile by-products, olfactory cues that are perceived by seed predators. Here, we examine the hypothesis that hard seeds are an anti-predator trait that evolved in response to powerful selection by small mammal seed predators. Seeds of two legume species with dimorphic seeds ('hard' and 'soft'), Robinia pseudoacacia and Vicia sativa, were offered to desert hamsters (Phodopus roborovskii) in a series of seed removal studies examining the differences in seed harvest between hard and soft seeds. Volatile compounds emitted by dry and imbibed soft seeds were identified by headspace gas chromatography-mass spectrometry (GC-MS). Fourteen main volatile compounds were identified, and hamsters readily detected both buried imbibed seeds and an artificial 'volatile cocktail' that mimicked the scent of imbibed seeds, but could not detect buried hard or dry soft seeds. We argue that physical dormancy has evolved to hide seeds from mammalian predators. This hypothesis also helps to explain some otherwise puzzling features of hard seeds and has implications for seed dispersal" |
Keywords: | Animals Cricetinae Plant Dormancy/*physiology Seeds/*physiology Smell/physiology Volatile Organic Compounds/metabolism; |
Notes: | "MedlinePaulsen, Torbjorn Rage Colville, Louise Kranner, Ilse Daws, Matthew I Hogstedt, Goran Vandvik, Vigdis Thompson, Ken eng England 2013/02/21 New Phytol. 2013 Apr; 198(2):496-503. doi: 10.1111/nph.12191. Epub 2013 Feb 20" |