Abstract
Self-pollen seldom results in vital genotypes and can thus be regarded as unimportant. Large-sized clones (clones with many ramets) are more exposed to self-pollen and spread more self-pollen and thus contribute relatively less than small-sized clones. The size of clones required to maximize genetic gain at given diversity, considering that only outcrossing contributes to successful gametes, was derived for tested clones intended to establish a Norway spruce (Picea abies) seed orchard. The derived optimal deployment was compared with linear deployment according to Lindgren and Matheson (Silvae Genet 35:173–177, 1986), where the size of a clone is deployed proportional to its breeding value. The study covered a range of effective numbers between 5 and 50. The results suggest that linear deployment is a good approximation to optimal deployment when only outcrossing is considered. The difference between the two strategies is decreased by increasing clone number and is negligible except at low effective numbers.
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Acknowledgements
This study was supported by “Föreningen Skogsträdsförädling” (FP and DL) and NSERC-IRC Grant (YAE). “Brödema Edlunds Fond” supported the visit of YAE to Umeå.
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Prescher, F., Lindgren, D. & El-Kassaby, Y.A. Is linear deployment of clones optimal under different clonal outcrossing contributions in seed orchards?. Tree Genetics & Genomes 2, 25–29 (2006). https://doi.org/10.1007/s11295-005-0027-8
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DOI: https://doi.org/10.1007/s11295-005-0027-8