Format: ORAL

Tejero P1,2, Calvo J3, Otamendi M2, Hermosilla B4, Urquiola L2, Ruiz A3, Martinez N2, Asiain M4, Aguinako I4, Zabala J4, Ferrndez JV, Ezquerra V, Villagrasa E5, Jon Zulaika6, Arrieta M2, Garmendia J2, Etxeberria M2, Agut A4, Navarro L7, Martnez-Ortega, M3 Palacio S1.

1 Instituto Pirenaico de Ecología-CSIC. Jaca. Spain. 2 Botanika Saila. Sociedad de Ciencias Aranzadi Zientzia Elkartea. Donostia. Spain. 3 Departamento de Botánica y Fisiología Vegetal, Facultad de Biología, Universidad de Salamanca. Spain. 4 Jardín botánico de olárizu. Ayuntamiento de Vitoria-Gasteiz. Spain. 5 Parque Nacional de Ordesa y Monte Perdido. Huesca. Spain. 6 Diputación de Gipuzkoa-Gipuzkoako Foru Aldundia. 7 Departamento de Biología Vegetal y Ciencias del Suelo, Universidad de Vigo. Vigo. Spain

Existing plant lineages may have experienced several climate changes during their evolution and they may have acquired strategies to cope with them. According to many indicators, our planet currently undergoes a very intense warming, which might accelerate extinction rates if plant species cannot adjust fast enough by either migration or adaptation. Cliff environments and their specialist plants are particularly relevant in this context, because they often have limited migration capacity, so their adaptive response might be intense. In this contribution, we present data derived from several experiments conducted with 11 taxa of the chasmophitic Iberian endemic genus Petrocoptis (CARYOPHYLLACEAE) investigating seed morphology, germination and their interaction with climate. All the species included in the genus showed high viability and in vitro germination rate, a couple of traits that might be adaptive in limiting substrates for plant stablishment such as cliffs. In general, warm temperatures decreased in vitro germination rate, except for species and populations from warmer climates. We detected a significant mother plant effect on the response of seed germination to temperature, and seeds from mothers behaving contrary to the main population trend were recurrently found. Interestingly, Petrocoptis seeds have a hygroscopic strophiole whose size in natural populations is associated with climate. We also conducted common garden and reciprocal ex situ cultures of P. crassifolia in a 1000-meter altitudinal gradient with contrasting climate. We confirmed the germination dependence on humidity but detected a high tolerance of the species to dry climates once plants were established in the pots. Overall, these results point at population level plasticity as one of the key drivers of cliff plant survival to changes in climatic conditions.