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A 10-day trip, encompassing 4600 km in the southeastern USA states of Tennessee, North Carolina, South Carolina, Georgia and Alabama, was made in October, 2003. Our primary objective was to locate populations of Helianthus eggertii, then on the USDI, Fish and Wildlife Service Threatened and Endangered Species list, and H. verticillatus, a candidate for endangered species status. Helianthus eggertii has since been de-listed (August 2005). An additional objective was to collect seeds of H. porteri, a species reclassified from Viguiera porteri, which is endemic to granite rock outcrops in Georgia. We collected seeds from 27 populations of the above three species plus three additional species, H. angustifolius, H. atrorubens, and H. smithii. Seed was deposited with the USDA-ARS North Central Regional Plant Introduction Station at Ames, Iowa (NCRPIS) from which 24 of the 27 collections are available for distribution. The three 'target' species were represented by 13 collections of H. eggertii, eight of H. porteri, and two of H. verticillatus; none of the three species were previously available from the NCRPIS sunflower collection. The availability of seed of these three species will allow researchers around the world the opportunity to investigate the potential of these wild Helianthus species to contribute useful traits to cultivated sunflower. Complete collection data has been loaded into the USDA-ARS Germplasm Resource Information Network (GRIN), and is available on the internet (www.ars-grin.gov). [ABSTRACT FROM AUTHOR]

The article presents the registration of two maintainer and three restorer Sclerotinia-tolerant oilseed sunflower germplasms. The two maintainers include HA 451 and HA 452. Two maintainer and three restorer oilseed sunflower germplasms were developed and released by the Agricultural Research Service of the U.S. Department of Agriculture and the North Dakota Agriculture Experiment Station. These germplasms were selected for their tolerance to Sclerotinia head and stalk rot which is a major sunflower disease. They also provide diversity for agronomic characteristics and oil quality. These germplasms are available for use by industry and public researchers to create hybrids, parental lines, or germplasms with increased tolerance to Sclerotinia head and stalk rot.

The article presents the registration of three maintainer oilseed sunflower germplasms. The three maintainers include HA 456, HA 457 and HA 412 HO. The germplasms were developed and released by the Agricultural Research Service of the U.S. Department of Agriculture, and the North Dakota Agricultural Experiment Station. These high-oleic germplasms are available for use by industry and public researchers to create hybrid, parental lines, or germplasms with a midoleic or high-oleic fatty acid concentration in the oil.

The article presents the registration of a sunflower germplasm resistant to rust, downy mildew, and virus, developed and released by the U.S. Department of Agriculture-Agricultural Research Service and the North Dakota Agricultural Experiment Station.

Sclerotinia head rot is a major disease of sunflower in the world, and quantitative trait loci (QTL) mapping could facilitate understanding of the genetic basis of head rot resistance and breeding in sunflower. One hundred twenty-three F2:3 and F2:4 families from a cross between HA 441 and RHA 439 were studied. The mapping population was evaluated for disease resistance in three field experiments in a randomized complete block design with two replicates. Disease incidence (DI) and disease severity (DS) were assessed. A genetic map with 180 target region amplification polymorphism, 32 simple sequence repeats, 11 insertion-deletion, and 2 morphological markers was constructed. Nine DI and seven DS QTL were identified with each QTL explaining 8.4 to 34.5% of phenotypic variance, suggesting the polygenic basis of the resistance to head rot. Five of these QTL were identified in more than one experiment, and each QTL explained more than 12.9% of phenotypic variance. These QTL could be useful in sunflower breeding. Although a positive correlation existed between the two disease indices, most of the respective QTL were located in different chromosomal regions, suggesting a different genetic basis for the two indices.