22 different types of the glutamat-oxaloacetate-transaminase (GOT) have been identified in European populations of three species of the Genus Capsella with the aid of gel electrophoresis. 17 of them were found in Capsella bursa-pastoris, 17 in Capsella grandiflora, and 19 in Capsella rubella. The frequency of six of the 22 bandings was smaller than one percent in all studied populations occurring between Greece and Scandinavia, while the six others had frequencies of more than 10 percent. Combinations of different types occur in the single populations. Each pattern represents a certain genotype. All in all, 214 different genotypes were found. Some of them appeared in all three species, while others are typical for one species each. 80 of the 214 different genotypes, for example, exist only in Capsella bursa-pastoris. Geographic differences in the distribution of certain GOT-bandings were identified (H. HURKA, University of Osnabrück, 1983).
This type of analysis shows that the variation of genotypes does not necessarily coincide with species boundaries. The intraspecific variation is just as big as the interspecific variation. These results can be compared to the already discussed situation of Clarkia speciosa , where a distribution boundary of two subspecies does not correspond with that of their caryotypes.
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