A review is given of some advances in the genetics of Rubus during the last decade. Particular attention is paid to fruit and seed anatomy, germination, the paucity of genes, and the distribution and instability of chromosome numbers. The embryology of sexual and apomictic species is described, and the possibility is suggested of using apomixis to produce virus-free raspberry stocks. Factors influencing the breeding system are discussed.
It is suggested that the present-day heterozygous polyploid apomicts may carry within them (but 'genetically imprisoned') the original diploid genomes that have survived the last glaciation. If they could be released, diploid forms would be obtained that have biologically survived since this era, and might not be too different from the extinct primary diploids.