Footnote

f Mutation experiments repeatedly found that the number of new mutants steadily declined, while the same type of mutants regularly appeared. Lönnig deduced from this phenomenon the “law of recurrent variation.” In addition, less than 1 percent of plant mutations were chosen for further research, and less than 1 percent of this group were found suitable for commercial use. The results of mutation breeding in animals were even worse than for plants, and the method was abandoned entirely.