title: Selection for production-related traits inPelargonium zonale: improved design and analysis make all the difference.
abstract: Ornamental plant variety improvement is limited by current phenotyping approaches and neglected use of experimental designs. The present study was conducted to show the benefits of using an experimental design and corresponding analysis in ornamental breeding regarding simulated response to selection inPelargonium zonalefor production-related traits. This required establishment of phenotyping protocols for root formation and stem cutting counts, with which 974 genotypes were assessed in a two-phase experimental design. The present paper evaluates this protocol. The possibility of varietal improvement through indirect selection on secondary traits such as branch count and flower count was assessed by genetic correlations. Simulated response to selection varied greatly, depending on the genotypic variances of the breeding population and traits. A varietal improvement of over 20% is possible for stem cutting count, root formation, branch count and flower count. In contrast, indirect selection of stem cutting count by branch count or flower count was found to be ineffective. The established phenotypic protocols and two-phase experimental designs are valuable tools for breeding ofP. zonale.
authors.affiliation: University of Hohenheim, Institute of Crop Science, Biostatistics Unit , Stuttgart 70599, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Molenaar
authors.affiliation: Klemm+Sohn GmbH & Co. KG , Stuttgart 70378, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Glawe
authors.affiliation: Klemm+Sohn GmbH & Co. KG , Stuttgart 70378, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Boehm
authors.affiliation: University of Hohenheim, Institute of Crop Science, Biostatistics Unit , Stuttgart 70599, Germany.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Piepho