Author
HENSON, ROBERT - NORTH DAKOTA STATE UNIV | |
Gulya Jr, Thomas | |
Radi, Scott | |
RAU, JACOB - NORTH DAKOTA STATE UNIV |
Submitted to: Proceedings Sunflower Research Workshop
Publication Type: Proceedings Publication Acceptance Date: 2/1/2004 Publication Date: 2/1/2004 Citation: Henson, R.A., Gulya Jr, T.J., Radi, S.A., Rau, J.J. 2004. Sunflower Sclerotinia head rot screening nursery. Sunflower Research Workshop Proceedings. 26th Sunflower Research Workshop, January 14-15, 2004, Fargo, ND. Available: http://www.sunflowernsa.com/research/research-workshop/documents/129.pdf Interpretive Summary: Evaluation of sunflower commercial hybrids at the NDSU Research and Extension Center in Carrington, ND for resistance to Sclerotinia head rot is now in its fourth year. Artificial inoculation with Sclerotinia spores, coupled with an automated mist irrigation system, ensures that each plant is subjected to a severe test for resistance. In 2003, companies entered 35 hybrids in this trial. Disease incidence at the end of the growing season ranged from 0% infection to 73%, illustrating that commercial hybrids have a wide range of susceptibility/resistance to this important disease. In a companion nursery, USDA breeding material are also evaluated, prior to being released. The ultimate goal of the USDA Sunflower Unit breeding program is to combine resistance to both Sclerotinia head rot and stalk rot into the same lines, and couple this resistance with good agronomic characters, including high oil content, high oleic acid, downy mildew resistance, and tolerance to IMI herbicides. Technical Abstract: The NDSU Research and Extension Center has had an automated mist irrigation system in place for four years, which has enabled their personnel and USDA scientists to artificially inoculate sunflower heads with Sclerotinia to evaluate their resistance to head rot. This screening nursery has been used to evaluate both commercial hybrids and USDA breeding material. In 2003, private seed companies submitted 35 hybrids for head rot testing. Head rot incidence at the end of the growing season ranged from 0% to 73% infection, illustrating that good progress has been made in the private sector to incorporate head rot resistance. The most resistant hybrids are being tested in multiple locations in subsequent years to substantiate their reactions to head rot. |