Congruence between theory and practice: reduced contamination rate following phenotypic pre-selection within the Breeding without Breeding framework

Abstract

Wind-pollinated seed orchards are often subjected to pollen intrusion from outside pollen sources. When wind-pollinated seed orchards seed are used to establish progeny trials, the offspring is expected to harbour varying proportion sired by outside sources. Theoretically the magnitude of selection differential between the orchard's population and the contaminant pollen sources will affect the proportion of offspring resulting from outside pollen sources matings. If phenotypic pre-selection is implemented through selecting the top phenotypically ranked individuals from these progeny trials, then it is expected that the proportion of individuals sired by outside pollen sources will be lower within the pre-selected vs. unselected individuals. Here, we present empirical data from two Scots pine progeny trials supporting these theoretical expectations. The observed reduced contamination rate among fingerprinted elite offspring was 3.9 and 4.2%, suggesting a significant reduction in comparison to reported contamination rates between 21 and 70% in Scots pine. Results provide support to the proposed phenotypic pre-selection during the implementation of Breeding without Breeding scheme.

Keywords:

• contamination rate
• phenotypic pre-selection
• Scots pine

Funding

This work was supported by the National Agency for Agriculture Research (NAZV, [grant number QJ1320013]; J. Korecký, M. Lstibůrek) as well as by the University-wide internal grant agency of CULS Prague – CIGA, project No. 20144301 (J. Korecký) and the Natural Sciences and Engineering Research Council of Canada (Discovery and IRC grants) and the Johnson's Family Forest Biotechnology Endowment to Y.A. El-Kassaby are highly appreciated.

Additional information

Funding

Funding: This work was supported by the National Agency for Agriculture Research (NAZV, [grant number QJ1320013]; J. Korecký, M. Lstibůrek) as well as by the University-wide internal grant agency of CULS Prague – CIGA, project No. 20144301 (J. Korecký) and the Natural Sciences and Engineering Research Council of Canada (Discovery and IRC grants) and the Johnson's Family Forest Biotechnology Endowment to Y.A. El-Kassaby are highly appreciated.