Abstract

The first section of this review examines the taxonomy of the genus. Of 12 recognized subgenera, only Idaeobatus, Eubatus, Cylactis and Chamaemorus contain species which produce edible fruit, the last mentioned containing only one species, R. chamaemorus. The other subgenera, however, are seen as potential sources of germplasm for Rubus breeding. The most important commercial species are the red raspberries, widespread in North America, Europe, Australia and Chile, and the black raspberries in North America. Blackberries and blackberry-raspberry hybrids are important only in western North America and New Zealand. Arctic raspberries are confined to parts of Sweden and Finland. The major cultivars and hybrids of each of these types are noted. The main problems which could be solved by breeding are seen as lack of environmental adaptation (to cold, heat, drought and low winter chilling), excess vigour, spininess, unsuitability for machine harvesting, poor fruit quality, low yield and susceptibility to pests and diseases. The wild and cultivated genetic resources available for solving these problems are extensively reported. The amount of genetic diversity in the crop is considered and efforts being made to preserve Rubus genetic resources are briefly noted.