Quantitative trait loci controlling water use efficiency and related traits in Quercus robur L

• Published in: Tree genetics & genomes 2008-04, Vol.4 (2), p.263-278
• Main Authors: Brendel, Oliver, Le Thiec, Didier, Scotti-Saintagne, Caroline, Bodénès, Catherine, Kremer, Antoine, Guehl, Jean-Marc
• Format: Article
• Language: English
• Subjects: Agricultural sciences; Biomedical and Life Sciences; Biotechnology; Carbon isotope composition; Forestry; Gas exchange; Gene mapping; Genetic diversity; Genetics; Genomics; Life Sciences; Nitrogen; Original Paper; Plant Breeding/Biotechnology; Plant Genetics and Genomics; QTL; Quercus robur; Silviculture, forestry; Stable isotopes; Stomatal conductance; Tree Biology; Vapor pressure; Water use; Water use efficiency; Water vapor; δ ¹³C
• ISSN: 1614-2942; 1614-2950
• DOI: 10.1007/s11295-007-0107-z

Genetic variation for intrinsic water use efficiency (W i) and related traits was estimated in a full-sib family of Quercus robur L. over 3 years. The genetic linkage map available for this F1 family was used to locate quantitative trait loci (QTL) for W i, as estimated by leaf carbon stable isotope composition (δ ¹³C) or the ratio of net CO₂ assimilation rate (A) to stomatal conductance to water vapour (g w) and related leaf traits. Gas exchange measurements were used to standardize estimates of A and g w and to model the sensitivity of g w to leaf-to-air vapour pressure deficit (sgVPD). δ ¹³C varied by more than 3[per thousand] among the siblings, which is equivalent to 40% variation of W i. Most of the studied traits exhibited high clonal mean repeatabilities (>50%; proportion of clonal mean variability in global variance). Repeatabilities for δ ¹³C, leaf mass per area (LMA) and leaf nitrogen content were higher than 70%. For δ ¹³C, ten QTLs were detected, one of which was detected repeatedly for all 3 years and consistently explained more than 20% of measured variance. Four genomic regions were found in which co-localizing traits linked variation in W i to variations in leaf chlorophyll and nitrogen content, LMA and sgVPD. A positive correlation using clonal means between δ ¹³C and A/g w, as well as a co-localisation of QTL detected for both traits, can be seen as validation of the theoretical model linking the genetic architecture of these two traits.