ABSTRACT
Beets have been cultivated for more than 2000 years in the eastern Mediterranean region, which is their center of origin. Beta vulgaris L. is an extraordinarily variable taxon, in which cultivated and wild forms are often difficult to distinguish (5,38). This is mainly due to the extensive use of sea beet (B. vulgaris ssp. maritima ARCANG.) gene resources in conventional breeding programs (36). Sea beet is primarily a coastal plant growing in drift line vegetation with a wide distribution from Cape Verde and the Canary Islands in the west, northward along the Atlantic coast to the North and Baltic Seas. It also extends eastward from the Mediterranean region into Asia with occurrences in Asia Minor, the central and outer Asiatic steppes, and desert areas as far as western India (31,51). Sea beet varies from self-compatible annuals to self-incompatible, polycarpic (repeatedly fruiting) perennials with a life span of 1 to 11 years (41,73). Cultivated B. vulgaris forms, including Swiss chard, red garden beet, and sugar beet, are biennial. The latter is partially selfincompatible due to the extensive use of male sterility genes in sugar beet breeding (49). All cultivated and wild subspecies of B. vulgaris are mostly wind-pollinated, although some insect pollination has been noted (8).
