Summary
The relative fitnes of genotypes is a function of the genotypic frequencies of two consecutive generations and of the rate of outcrossing. The use of mean values for cross-fertilization can lead to wrong estimates of fitness values if the mating system depends on the genotype. Using experimentally obtained genotypic frequencies, the infuence of mistaken estimates of outcrossing rates on the fitness value are investigated and discussed in this paper. These results showed that a very cautious interpretation is necessary if one uses pooled values of outcrossing rather than those pertaining to each individual genotype, especially when there are small differences between the relative fitness values and large genetic variability in the mating systems.
Zusammenfassung
Die relative „fitness” von Genotypen ist eine Funktion der Genotypenfrequenzen zweier aufeinander folgender Generationen und der Fremdbefruchtungsrate. Die Berücksichtigung von Durchschnittswerten rate. Die Berücksichtigung von Durchschnittswerten für die Fremdbefruchtung kann bei vom Genotyp abhängendem Befruchtungssystem zu Fehlschätzungen der Fitnesswerte führen. Unter Verwendung von experimentell ermittelten Genotypenhäufigkeiten wird in vorliegender Arbeit der Einfluß einer Feschätzung der Fremdbefruchtungshäufigkeit auf den Fitnesswert untersucht und diskutiert. Dabei ergab sich, daß vor allem bei geringen Differenzen zwischen den relativen Fitnesswerten sowie großer genetisch bedingter Variabilität des Befruchtungssystems eine vorsichtige Interpretation notwendig ist, wenn anstelle der dem Genotyp eigenen Fremdbefruchtungs-rate lediglich ein gemeinsamer Wert berücksichtigt wird.
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Wöhrmann, K. Fremdbefruchtungsrate und genotypische „fitness”. Züchter / Genet. Breed. Res. 37, 142–145 (1967). https://doi.org/10.1007/BF02440098
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DOI: https://doi.org/10.1007/BF02440098