The effect of inbreeding in Cyclamen

Abstract

In order to establish the effect of inbreeding in Cyclamen, one motherplant of ‘Rose van Aalsmeer’ was used to produce successively five inbred generations, I₁, I₂, I₃, I₄, and I₅. Similarly, one motherplant of ‘Wit met oog fimbriata’ was used for the production of an I₁, an I₂ and an I₃. By keeping the motherplants alive, plants could be obtained which, although belonging to different generations, were of the same age. Comparison of the numbers of flowers formed by these plants during their first flowering season showed a clear effect of inbreeding, especially in the I₃, I₄ and I₅, consisting of a significant reduction of the mean number of flowers. When two inbred lines, either of one variety or belonging to the two different ones, were crossed, the F₁ reached the level of the I₁. In both cultivars there were rather large differences among individual lines, some showing a strong effect of inbreeding, while in others the effect was only slight or sometimes even absent.