Our laboratory maintains operations of a 6 decades old sunflower breeding program, to make new traits of importance to consumers and producers available to breeding companies and other public sector breeders. Our released inbred lines are available by “public release”, meaning that we do not enter into contracts for exclusive rights to our new sunflower lines or demand royalty payments for their use. This free and open policy has resulted in our lines being the center of genomics research in sunflower. Currently, we have programs focusing on the following traits:
- High-oleic, low-saturated fat oils
- Resistance to diseases, such as Sclerotinia, Phomopsis stalk canker, downy mildew, and rust
- Resistance to insects, especially red sunflower seed weevil, sunflower head moth, and sunflower banded moth
- Herbicide resistance, especially imidazolinone resistance
- Increased yield and oil content
- Greater yield stability over environmental gradients
Sunflower is a hybrid crop, meaning that finished varieties grown by producers are the result of a cross between two highly inbred lines, accomplished on a field-scale with the help of insect pollinators. Unlike some major crops, such as wheat and soybean, sunflower varieties have high heterozygosity but low heterogeneity as a result of the hybrid breeding process. In the field, sunflower varieties are as uniform as other crops, but benefit to some degree by hybrid vigor (aka “heterosis”).
The success story of sunflower genetic improvement since becoming a hybrid crop in the early 1970s is not as noteworthy as success stories in other crops with the same hybrid system. Some believe that this is the result of too many (and sometimes conflicting) breeding goals, lack of resources to achieve all the goals, and reliance on a cytoplasmic male sterility system on the female side of the hybrid cross, which requires technically inefficient backcross breeding on a massively parallel scale. Our lab has academic interest in addressing these issues, which is about half of our total effort. Here are some of the main projects we are involved in:
- Doubled haploid method development to reduce inbred line production to about one year
- Development of genomics-assisted methods to predict yield and other traits in new inbred lines, given data on ancestors (so-called genomic selection or genomic prediction)
- Development of marker-based models for Sclerotinia and Phomopsis resistance, as well as abiotic stresses including flood, drought, salt, and low-nutrient.
We collaborate extensively with other public and private groups throughout the world on sunflower and sunflower-like species. An interesting new collaboration involves domestication of Silphium integrifolium, a sunflower-like species that has very high kernel : hull ratio and oil quality/quantity similar to landrace sunflower, making it an ideal oilseed crop candidate. It is also perennial and extremely drought resistant, which may make it an important species in certain marginal environments prone to drought and soil erosion.
If you have an interest in the research we do, or are looking for graduate study or postdoctoral opportunities, please feel free to contact Dr. Brent Hulke and ask!