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The necessity for testing germination of fresh seeds in studies on diaspore heteromorphism as a life-history strategy

Published online by Cambridge University Press:  10 May 2013

Jerry M. Baskin
Affiliation:
Xinjiang Key Laboratory of Grassland Resources and Ecology and Ministry of Education Key Laboratory for Western Arid Region Grassland Resources and Ecology, College of Grassland and Environment Sciences, Xinjiang Agricultural University, Urümqi 830052, China Department of Biology, University of Kentucky, Lexington, KY 40506, USA
Juan J. Lu
Affiliation:
Xinjiang Key Laboratory of Grassland Resources and Ecology and Ministry of Education Key Laboratory for Western Arid Region Grassland Resources and Ecology, College of Grassland and Environment Sciences, Xinjiang Agricultural University, Urümqi 830052, China
Carol C. Baskin*
Affiliation:
Xinjiang Key Laboratory of Grassland Resources and Ecology and Ministry of Education Key Laboratory for Western Arid Region Grassland Resources and Ecology, College of Grassland and Environment Sciences, Xinjiang Agricultural University, Urümqi 830052, China Department of Biology, University of Kentucky, Lexington, KY 40506, USA Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546, USA
Dun Y. Tan
Affiliation:
Xinjiang Key Laboratory of Grassland Resources and Ecology and Ministry of Education Key Laboratory for Western Arid Region Grassland Resources and Ecology, College of Grassland and Environment Sciences, Xinjiang Agricultural University, Urümqi 830052, China
*
*Correspondence Fax: 1-859-257-1717 E-mail: ccbask0@uky.edu

Abstract

Many studies have compared diaspore dispersal ability and degree of dormancy in the two diaspores of dimorphic plant species. A primary goal of these studies was to determine if germination and dispersal characteristics of the two morphs fit within a high risk–low risk (bet-hedging) life-history strategy, i.e. high dispersal/low dormancy in one morph versus low dispersal/high dormancy in the other one. In a survey of 26 papers on 28 diaspore dimorphic species, we found that in 12 of the studies, which were published between 1978 and 2008, seeds were stored, and thus possibly afterripened, before they were tested for germination. The 14 papers that tested fresh seeds were published between 1963 and 2010. Failure to test fresh seeds likely resulted in misinterpretation of the diaspore dispersal/dormancy strategy in some of the species investigated. We conclude that it is imperative that fresh seeds be tested for germination in order to be certain that the correct relationship between dispersal and dormancy is elucidated, and thus that the correct interpretation is made concerning life-history strategy and bet-hedging, in dimorphic species.

Type
Research Opinion
Copyright
Copyright © Cambridge University Press 2013 

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