Genome size:

Simonovik B, Ivancic A, Jakse J, Bohanec B. Production and genetic evaluation of interspecific hybrids within the genus Sambucus. Plant Breeding (2007) 126:628-633
Besnard G, Garcia-Verdugo C, Rubio De Casas R, Treier UA, Galland N, Vargas P. Polyploidy in the Olive complex (Olea europaea): evidence from flow cytometry and nuclear microsatellite analyses. Annals of Botany (2008) 101: 25-30

Ploidy level:
Schönswetter P, Lachmayer M, Lettner C, Prehsler D, Rechnitzer S, Reich DS, Sonnleitner M, Wagner I, Hülber K, Schneeweiss GM, Trávnícek P, Suda J. Sympatric diploid and hexaploid cytotypes of Senecio carniolicus (Asteraceae) in the Eastern Alps are separated along an altitudinal gradient. Journal of Plant Research (2007) 120:721-725
Tiébré MS, Bizoux JP, Hardy OJ, Bailey JP, Mahy G. Hybridization and morphogenetic variation in the invasive alien Fallopia (Polygonaceae) complex in Belgium. American Journal of Botany (2007) 94:1900–1910

Abel S, Becker HC. The effect of autopolyploidy on biomass production in homozygous lines of Brassica rapa and Brassica oleracea. Plant Breeding (2007) 126:642-643

Kao RH. Origins and widespread distribution of co-existing polyploids in Arnica cordifolia (Asteraceae). Annals of Botany (2008) 101:145–152
Mráz P, Singliarová B, Urfus T, Krahulec F. Cytogeography of Pilosella officinarum (Compositae): altitudinal and longitudinal differences in ploidy level distribution in the Czech Republic and Slovakia and the general pattern in Europe. Annals of Botany (2008) 101:59-71