Genome Size Study in the Valerianaceae: First Results andNew Hypotheses

[摘要] The purpose of this study is to provide a new focus to contribute, from the perspective of genomic evolution, towards a better understanding of the Valerianaceae evolutionary history. Chromosome numbers were determined by Feulgen staining in 24 populations of 18 species (first count forValerianella multidentata,2n=2x=14–16), and DNA contents were assessed by flow cytometry in 74 populations of 35 species (first assessments in all taxa butCentranthus ruber). A molecular phylogeny based on thetrnL-trnF and including 41 new sequences was established, with the first DNA sequence forCentranthus nevadensis,Valeriana rotundifolia,V. saxatilis,Valerianella multidentata, andV. turgida. This work is the first large genome size study devoted to the Valerianaceae, showing a range of DNA amounts from2C=0.39 pg (Valerianella turgida) to2C=8.32 pg (Valeriana officinalis). At the family level, changes in basic chromosome number and genome size coincide with or precede major shifts in the evolutionary history of the group, such as those concerning stamen number and floral symmetry.

[学科分类] 植物学