Location: Sunflower and Plant Biology Research
Project Number: 3060-21000-047-000-D
Project Type: In-House Appropriated
Start Date: Mar 12, 2023
End Date: Mar 11, 2028
Objective 1. Conduct research to develop high yielding sunflower germplasm and inbred lines with adaptation to a wide range of production environments and resistance or tolerance to abiotic and biotic stressors. Subobjective 1A: Investigate genetic basis of Phomopsis resistance and introduce new disease resistance genes from wild sunflower species into cultivated sunflower. Subobjective 1B: Characterize mechanisms of sunflower resistance to Phomopsis stem canker pathogens and responses to necrosis-inducing culture filtrates. Subobjective 1C: Evaluate diverse interspecific germplasm for resistance to Phomopsis, rust, and downy mildew. Subobjective 1D: Develop advanced sunflower inbred line germplasm with novel traits or combinations of agronomically important traits. Objective 2. Conduct research to elucidate the effects of environmental variation on economically important sunflower traits and/or genes related to host plant resistance of insect pests and provision of resources for pollinators such as superior pollen nutrition and nectar quality for use in breeding. Subobjective 2A: Evaluate planting date and hybrid effects on damage by the red sunflower seed weevil and test host plant resistance under extremely high weevil populations. Subobjective 2B: Evaluate plant genetic and environmental effects on nectar and pollen rewards.
Sunflowers are a source of heart-healthy oil and other products with low saturated fats and no trans fats. In farming rotations, sunflower is considered a low-input crop that helps limit problems with weeds or diseases in other crops. However, sunflower growers are challenged to find hybrids that use elite germplasm with proven adaptation to their growing regions, incorporating host plant resistance to the pathogens and insects that reduce average yields and consistency of yields. In particular, increasing problems with Phomopsis stem canker (PSC) and red sunflower seed weevil (RSSW) in the U.S. have not been adequately addressed by a seed industry that has been moving research and breeding out of North America. The proposed research will advance sunflower production by (1) developing genetic markers for resistance to major sunflower diseases, (2) investigating specific mechanisms of resistance to PSC, (3) identifying new sources of genetic resistance to sunflower diseases, (4) evaluating resistance and early-maturity as tools to manage RSSW, (5) examining factors that influence sunflowers’ nectar and pollen rewards to pollinating insects (which support crop yields), and (6) combining desired traits to create superior germplasm that is adapted to the major North American growing environments. Success in the Project Plan components will provide improved genetic resources for commercial sunflower breeders, new options for growers to manage biotic and abiotic stresses to their crop, and support a stable, affordable supply of sunflower products to consumers.