Submitted to: Crop Science
Publication Type: Abstract Only
Publication Acceptance Date: October 25, 2001
Publication Date: N/A
Technical Abstract: Sunflower (Helianthus annuus L.) is one of the few native crops of North America. The genus Helianthus consists of 50 species, 14 annual and 36 perennial, and 19 subspecies. Having the wild relatives of the crop available within the boundaries of the USA has facilitated the collection of wild sunflower germplasm. Ten explorations covering the USA and Canada have been undertaken since 1980. Since the establishment of the wild sunflower germplasm collection in 1976, over 2200 accessions have been added to the collection, which is located at the North Central Regional Plant Introduction Station at Ames, Iowa. It is now the largest and most complete wild sunflower collection in the world having representative populations of all extant species. The sunflower crop has a long history of utilizing wild germplasm to increase its genetic diversity and economic value. The economic impact of the sunflower industry in the USA alone is 2.6 billion dollars annually, of which the wild species contribute an estimated 269.2 million dollars. Wild species are the source of the male sterile cytoplasm used in most commercial hybrids, and of several resistance genes for prevalent sunflower pathogens. Germplasm from the wild sunflower collection has been used extensively to diversify the genetics of sunflower to make it an adaptable, viable, and sustainable crop.