Authors: María E Amat Pablo Vargas José M Gómez
Publish Date: 2014/03/28
Volume: 300, Issue: 9, Pages: 2127-2134
Abstract
Many seeds are dormant when shed from the mother plant This unique characteristic of plants poses challenges in conservation and many different treatments have traditionally been used to break dormancy When germination only occurs under certain circumstances recruitment may be insufficient and the viability of plant populations may be threatened A marked dormancy was previously identified in the Iberian critically endangered species Pseudomisopates rivasmartinezii The present study aimed to determine the magnitude of dormancy by estimating seed viability under different germination treatments heat ash stratification gibberellin addition and darkness Our results indicate that there were significant differences in viability across plant populations and treatments Maximum seed germination was obtained under ash addition although cold stratification alone gave a considerable enhancement However gibberellic acid did not improve germination and darkness had a diminishing effect In conclusion a cold period is required for the species to germinate coupled with the effects of fire 1 ash 2 vegetation clearings and 3 resprouting which are major factors triggering seed germination Although these conditions are widely found in the field we hypothesize that a more dramatic situation may have tackled this species before the increase of humanmediated fires in the past millenniaWe thank Bernardo García Muñoz for information on populations and Juan Lorite for technical advice The Consejería de Medio Ambiente of the Junta de Castilla y León granted permission to work in Gredos Regional Park This research was supported by the Spanish General Direction of Scientific and Technical Research DGICYT through the projects CGL20091003 and FGCSIC2010 and a Spanish MARM grant 078/2007 MEA was supported by an FPU fellowship AP20050160 from the Spanish Ministry of Education
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