Phenomics of Picea abies: characterization of phenotypic traits involved in long-term adaptation to climate change and their genetic base

Norway spruce (Picea abies (L.) Karst) is one of the ecologically and economically (timber, tourism) most important tree species in the Trentino-Alto Adige region as well as in the whole of Europe. Considered the current climate change scenarios, a full understanding of the functioning of given complex traits and their genetic base appears to be the only effective way to cope with effects that may be a menace to the performance and the survival of this species. Adaptation to drought stress is among the greatest challenges to forest trees in the current climate change scenario. In spring 2013, a Norway spruce common garden was established at the Casteller (Trento) nursery run by the Forest service of the Provincia Autonoma di Trento. In early May seeds from 520 certified families covering the entire Alpine range (in cooperation with WSL Switzerland, BFW Vienna, INRA Avignon) seeds were planted as to obtain a half-sib population of 7750 individuals, 15 individuals per family. Mother trees were selected so as to best capture the ecological and specific diversity of Alpine P. abies ecosystems. Growth and phenology traits assessed were: germination time, bud burst and bud set, height at the end of the vegetation period. Parallel to the establishment of the common garden, DNA was extracted from needles and from mega gametophytes (IGV- CNR, Sesto Fiorentino) so as to perform the genotyping of a chip of 384 single-nucleotide polymorphisms (SNP) designed from previous work on Picea spp. (Chen et al. 2011; Canadian Arborea Project (http://www.arborea.ulaval.ca); Scalfi et al. submitted). A candidate gene-based approach will be then used to search for genetic association between single-nucleotide polymorphisms (SNP) markers detected in candidate genes putatively involved in the control of the measured adaptive traits and the observed phenotypic variation. The discovery of polymorphisms that underlie adaptive phenotypic traits is a fundamental goal of molecular genetics. Elucidation of the genetic components for ecologically relevant traits through association mapping at markers in candidate genes has been achieved for a variety of adaptive phenotypes in other tree species, and it has important putative applications ranging from marker assisted breeding to gene conservation in the face of climate change