While Sclerotinia head and basal stalk rot and downy mildew have long caused problems for the sunflower (Helianthus annuus L.) production industry, Phomopsis stem canker is a disease that is a growing issue in the United States. Our goal was to provide germplasms that contain resistance to one or more of these problematic fungi while also upholding necessary agronomic traits, including high yield and tolerance to imidazolinone herbicides. RHA 485 (Reg. no. GP-356, PI 690018) and RHA 486 (Reg. no. GP-357; PI 690019) are restorer inbred germplasms developed by pedigree method and testcross evaluation. RHA 485 has high-yield potential with high-oil content and low Phomopsis and Sclerotinia head rot incidences in the field. RHA 486 possesses high-yield potential, resistance to Phomopsis (average incidence near 0%), and low incidence of Sclerotinia basal stalk rot. HA 487 (Reg. no. GP-358, PI 690442) is a maintainer inbred line that has potential for high yield, with Sclerotinia head rot scores that are comparable to the best available checks. These lines were released by the USDA-ARS, Fargo, ND, to fill the need for germplasms with resistance to multiple diseases in addition to other important agronomic traits.

Necrotropic pathogens such as Sclerotinia sclerotiorum (Lib.) de Bary (causing Sclerotinia head and stalk rots) and Diaporthe spp. (causing Phomopsis stem cankers) have resulted in yield loss for the sunflower (Helianthus annuus L.) industry. The combination of durable disease resistance and high yield potential is needed for increasing crop productivity and resilience. Our goal is to develop public inbred germplasms with high yield potential, tolerance to imidazolinone herbicides, and enhanced oilseed traits while adding genes for improved resistance to necrotrophic pathogens. RHA 478 (Reg. no. GP-359, PI 688040), RHA 479 (Reg. no. GP-360, PI 688041), and RHA 480 (Reg. no. GP-361, PI 688042) are restorer inbred germplasm lines, and HA 481 (Reg. no. GP-362, PI 688037) is a maintainer inbred germplasm developed with the pedigree breeding method and testcross hybrid trials for agronomic and disease evaluation. RHA 478, RHA 479, RHA 480, and HA 481 have high yield potential combined with disease resistance, and RHA 478 and HA 481 have high oleic acid in the seed oil. The lines were released by the USDA-ARS in Fargo, ND, to provide germplasms with resistance to multiple diseases while also containing valuable agronomic traits.

Sclerotinia diseases and Phomopsis stem canker, among the most serious diseases threatening the success of sunflower (Helianthus annuus L.) production across the world, have been of increasing concern in recent history, and there is a need for additional inbred lines with resistance to these diseases. While breeding new lines capable of thriving in agricultural landscapes riddled with these widespread diseases, it is essential that lines also exhibit other desirable traits such as high yield potential, satisfactory fatty acid composition (e.g., high oleic acid), and herbicide tolerance (e.g., to imidazolinones), along with overall agronomic performance suitable to the northern Great Plains climate in the United States, and similar climates across other continents. A maintainer inbred germplasm line, HA 482 (Reg. no. GP-364, PI 690015), and two restorer inbred germplasms, RHA 483 (Reg. no. GP-365, PI 690016) and RHA 484 (Reg. no. GP-366, PI 690017), have been developed with the pedigree breeding method, evaluated through the use of testcross hybrid trials for both disease resistance and agronomic traits, and released by the USDA-ARS, Fargo, ND. All three lines have high oleic acid composition in the seed oil and exhibit resistance to Sclerotinia and Phomopsis stem canker, and both RHA 483 and RHA 484 are imidazolinone tolerant.

The banded sunflower moth is one of the most pervasive insect pests of sunflower (Helianthus annuus L.) in North America, in large part due to its ability to overwinter in cold climates. The goal of this research is to provide germplasm containing resistance to infestation by the banded sunflower moth while retaining valuable traits, such as imidazolinone herbicide tolerance and high oleic acid content in the seed oil, along with suitable agronomic performance for the northern Great Plains climate and other similar climates where the banded sunflower moth is prevalent. HA 489 (Reg.no. GP-370, PI 691858) is a maintainer inbred germplasm developed by pedigree selection and testcross evaluation that can fill this need. HA 489 has high oleic acid composition, exhibits tolerance to imidazolinones, and provides resistance to banded sunflower moth infestation. This line was released by the USDA-ARS, Fargo, ND, to fill the need for sources of host-plant resistance to important insect pests.

Sunflower (Helianthus annuus L.), as a native crop, has numerous insect pests that cause economic damage to producers in the United States. The red sunflower seed weevil is a notable seed‐infesting insect pest throughout the U.S. sunflower growing region that is controlled only by insecticides; therefore, growers would benefit from host‐plant resistance to help mitigate the economic costs associated with infestation. HA 488 (Reg. no. GP‐369, PI 691857) is a maintainer inbred germplasm developed by pedigree selection that provides resistance to the red sunflower seed weevil. HA 488 is as resistant to red sunflower seed weevil as the donor parent PI 431542, an open‐pollinated variety that was previously shown to be one of the most resistant sunflower varieties in a diversity panel. HA 488 was released by the USDA‐ARS, Fargo, ND, to fill the need for sources of host‐plant resistance to important insect pests.