Knopmutatie bij den aardappel : en hare beteekenis voor den landbouw

Gradual deterioration during vegetative propagation had never been demonstrated in the potato but sudden changes which remain constant had repeatedly been described. However, erroneous conclusions might result from admixtures, modifications and diseases. A collection of bud mutations, mainly from the varieties Eigenheimer (18 items), and Roode Star (12 items), contained several morphological types as well as colour.
Experimental proof of bud mutations was by separate propagation from different sectors of chimeric plants. Thus, with blue/yellow chimeric tubers of Eigenheimer, eyes from the blue and yellow sectors gave plants with blue and yellow tubers, respectively. Similarly, tubers from normal and raspberry-leaf stems gave normal and raspberry-leaf plants, respectively. In total 7 bud mutations were studied in this way. Some of the bud mutations reverted.

No definite conclusions could be reached about the origin of bud mutations. Where the character was not transmitted through potato seeds, it was tentatively suggested that the subepidermal layer did not contain the mutation. Induction of adventitious buds in different layers may lead to a better understanding.

The importance was emphasized of clonal selection to remove bud mutations to maintain uniformity, and to propagate and test types of possible agricultural value.