Coevolution of apomixis and genome size within the genus Hypericum

摘要: Trends concerning coevolution of mode reproduction and genome size were elucidated by screening both components in 71 species/subspecies the genus Hypericum. Two independent agamic complexes identified (sections Ascyreia with ten, Hypericum five apomictic species). In phylogenetically younger section Hypericum, relative DNA content apomicts is increased solely polyploidy. The evolutionarily older have significantly larger genomes than all other species due to polyploidization higher per chromosome. An accumulation retroelements might be one reason for genomes. male fertility was reduced compared sexuals, although facultative pseudogamous, forming gametes. Another form apomixis (obligate pseudogamous unreduced gametes), probably indicating an escape from interspecific sterility, found H. scabrum, only case asexual seed formation outside sections described scenario evolution relation deserves consideration harnessing apomixis.