Transgenic Gerbera

Abstract

Gerbera (family Asteraceae), comprising ca. 30 species, extends to Africa, Madagascar, tropical Asia, and South America (Hansen 1985; Bremer 1994). The first official description of the South African species Gerbera jamesonii, also know as Transvaal daisy or Barberton daisy, was made by J.D. Hooker in 1889 in the Curtis Botanical Magazine (Penningsfeld and Forchthammer 1980). It bears a large capitulum with prominent, yellow, orange, white, pink, or various red-colored ray florets (Hansen 1985). The breeding of gerbera started at the end of the 19th century in Cambridge, England, when two South African species. G. jamesonii and G. viridifolia, were crossed by R.I. Lynch. He named the hybrid Gerbera × cantebrigiensis, known today also as Gerbera hybrida. The majority of the present commercially cultivated varieties originate from the crossing progenies of these two species. Natural hybrids of the two species have not been found (Hansen 1985). It is possible that also other wild gerbera species have been used in breeding, but hardly any information exists (Penningsfeld and Forchthammer 1980). Already at the turn of the century, gerbera was cultivated in England, Belgium, the USA, Germany, and Italy (Penningsfeld and Forchthammer 1980). Today, gerbera is known as an important article of trade and it belongs to the most important ornamental plant species in the world, together with rose, chrysanthemum, carnation, and tulip. In 1991 gerbera was ranked sixth in sales through Dutch flower auctions (Anonymous 1992) and it is sold both as cut flowers and pot plants.