Autogamy depression

[2] Any deleterious mutations that appear during mitotic growth are filtered out through cell lineage selection, in which deleterious mutations that are subject to developmental selection during mitotic growth are replaced by vigorous cell lineages, however, somatic mutations that are not expressed will not be subject to selection during growth of the plant and will accumulate in the apical meristem.

[4] There is evidence of the phenotypic effects of somatic mutations in increased chlorophyll mutants of some long-lived plants.

Because of the highly conserved nature of photosynthetic processes, these chlorophyll mutation rates can be generalized to most angiosperms.

[5] Somatic mutations accumulating during vegetative growth have also been found to affect the fitness of seedlings in the next generation.

[3] Individual crowns are treated as "independent mitotic mutation-accumulation lines"[1] and so the appearance of deleterious somatic mutations in the autogamous crosses will be heterozygous or homozygous at the same locus (~25% homozygous)[4] and the appearance of deleterious somatic mutations in the geitonogamous crosses will be heterozygous.