Progress 03/01/10 to 02/28/14

Outputs
Target Audience: Nothing Reported Changes/Problems: PROJECT MODIFICATIONS: Dr. William Berzonsky, former project PI, left the employ of South Dakota State University in May, 2013 for a position in industry, and Dr. Jose Gonzalez assumed responsibilities as project PI. What opportunities for training and professional development has the project provided? Students who completed PS741 over this period of the study acquired skills and learned breeding strategies that are unique to both self and cross-pollinated crops, but they also learned of breeding techniques that are applied to both types of crops, but for different outcomes. For example, line breeding strategies and techniques are still characteristic of self-pollinated crops; whereas, hybrid breeding strategies and techniques are still characteristic of cross-pollinated crops. Doubled-haploid lines are produced in self-pollinated crops to hasten the development of pure-lines and the release of varieties, and doubled-haploid lines are produced in cross-pollinated crops to hasten the production of inbred parents for hybrids. Also, few haploid-inducers are used to produce the haploids in the self-pollinated crops, while haploid-inducers are the more the norm for cross-pollinated crops. The exposure of students to both private and public breeding programs is expected to have a deep and lasting impact on them. Many students, particularly the undergraduate students, are still forming ideas about what career to pursue. We expect that some of these students will change their career path, or at least consider plant breeding as a career, which likely would not have happened had they not seen professionals in both private industry and academia who have made a career out of plant breeding. We estimate that as many as 40 to 50 students, both graduate and undergraduate have enrolled and taken PS741 since its inception as a result of this project. Several manuscripts will be prepared in 2014 to publish results and to demonstrate the contributions of this study to the scientific literature. One publication is expected to illustrate why breeders and geneticists should anticipate some difficulty in trying to pyramid with markers for such host resistance genes as Lr10 and Lr21. To our knowledge, there have heretofore been no publications to describe this obstacle and enable breeders and geneticists to strategize about how to overcome this obstacle. Other publications are expected to describe the impact of allopurinol treatments on ROS disease and disease-like reactions, such as hybrid necrosis and lesion mutations in wheat. Current theory, as published in the scientific literature, is that hybrid necrosis is a ROS-dependent reaction, or an autoimmune type of reaction when one parent of a cross reacts to something in the opposite parent as if it is being challenged by a pathogen. Our initial results suggest this theory is correct, and we expect to demonstrate this with a publication that shows that wheat plants expressing hybrid necrosis improve in the production of tillers and seed in an almost linear fashion to allopurinol treatments. Similarly, initial results suggest the leaf lesions expressed by wheat mutants can be reduced with allopurinol treatments. If this is quantified, the published results will support the more general theory that ROS are critical to various cell death mechanisms in wheat. Furthermore, such proof will argue for the use of these mutants and the suppression of ROS mechanisms as a way to model disease reactions and the cost of these disease reactions to wheat. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Plant Breeding Techniques (PS741) was established as a new course at South Dakota State University since the initial year of project funding. The course is offered each fall and has continued to offer students hands-on experience in hybridizing both self and cross-pollinated crops. Videos and training modules on hybridizing crops were recorded and offered to students in 2012, and these remain as instruction resources for the course. The course has averaged approximately 10 students per semester that it has been taught and it has been offered to approximately 40 to 50 undergraduate and graduate students at South Dakota State University. Over the course of the project and since 2009, virtually every plant breeding graduate student in matriculated into the Plant Science Department has enrolled and taken the course. taught for the second time. Students have been provided the opportunity to interact with breeders and staff personnel working with both cross and self-pollinated crops, such as; corn, soybean, sunflower, and wheat. In addition, students have been offered a balanced perspective on the crop breeding activities that take place in private companies, by visiting companies, such as; Pioneer and Monsanto, as well as public breeding programs, such as; the North Dakota State University Corn Breeding Program (Fargo, ND), and the USDA-ARS Sunflower Breeding Program (Fargo, ND). One MS student will be graduating in the spring of 2014, and her thesis title will be "Characterizing the Fitness Cost to Wheat (Triticum aestivum L.) Genotypes with Multiple Leaf Rust Resistance Genes". She has produced various 'Thatcher' spring wheat NILs that have combinations of leaf rust resistance genes; Lr10, Lr21, Lr34. Her research has demonstrated that the non-host specific oat crown rust pathogen might be useful in invoking a leaf rust response in wheat without the formation of rust pustules. Thus, the crown rust pathogen/wheat host might be a feasible system to assess the cost of expressing resistance in wheat. As they are very similar in their genetic composition and in expressing hypersensitivity, Lr10 and Lr21 may exact similar fitness costs in wheat compared with Lr34. The slow-rusting gene Lr34 is relatively different than Lr10 and Lr21 in its genetic composition and in its response to a pathogen challenge. It may be these differences and differences in the energy it takes to express the different genes that can cause differences in the cost to the fitness of the plant. This student's research also demonstrated that genes Lr10 and Lr21 are so similar that breeders and geneticists must use caution in applying markers to pyramid the genes into a single genotype. It proved difficult to distinguish the genes even using perfect markers developed from the cloned genes, since Lr21 in particular, also produces mutations that lead to pseudogenes and paralogs. Hence, the similarity of Lr10 and Lr21 as well as the mutations for Lr21 make it more difficult that might be anticipated to follow with markers pyramiding these genes into a single genotype. Two additional students are using allopurinol to disrupt hypersensitive reactions in wheat and sunflower to assess the cost of resistance to these crops. Hybrid necrosis in wheat is thought to involve ROS and cell death in a similar fashion to a hypersensitive disease reaction. First trial results with allopurinol show an almost linear increase in reproductive traits for wheat plants expressing hybrid necrosis and treated with increasing amounts of allopurinol. Similarly, when treated with allopurinol, a lesion mutant in wheat seems to express lesions of reduced size, which possibly results in an improvement in seed yield and other reproductive characteristics. These trials are being repeated, and inoculated trials using sunflower and allopurinol treatments are also being conducted. Several publications are expected from expected outcomes from each of these trials. Sunflower lines with unique leaf rust resistance genes have been hybridized, and for the first time, hybrids genotypes putatively having several of these genes are expected to be available to breeders and geneticists for the first time. As with the wheat NILs, one outcome will be the release of these lines as unique germplasm for additional studies addressing leaf rust resistance.

Publications

• Type: Conference Papers and Presentations Status: Published Year Published: 2013 Citation: Berzonsky, W.A., K.D. Glover, J.L. Gonzalez-Hernandez, and K.A. Grady. 2013. Assessing the cost to pyramiding host resistance to biotic stress in crop species. Oral presentation, USDA-NIFA Project Director Meeting, Jan. 11, preceding PAG XX Meetings, Jan. 12-16, San Diego, CA.

Progress 03/01/11 to 02/28/12

Outputs
OUTPUTS: In the fall of 2011 (Aug. to Dec. 2011), Plant Breeding Techniques (PS741) was taught for the second time. Eleven students were enrolled in the course, and two students were undergraduates. Students were provided the opportunity to interact with breeders and staff personnel working with both cross and self-pollinated crops, such as; corn, soybean, sunflower and wheat. Compared to the first year of the project and as a consequence of visiting Pioneer and Monsanto corn and soybean breeding programs, students were exposed to a more balanced perspective on public and private breeding programs. Examples of breeding programs and plant breeders who interacted with PS741 students included; the NDSU Corn Breeding Program (Fargo, ND), the USDA-ARS Sunflower Breeding Program (Fargo, ND), the Pioneer SoybeanBreeding Program (Volga, SD) and the Monsanto Corn and Soybean Breeding Programs (Harrisburg, SD). Hybridizations were made to pyramid host leaf rust genes in both wheat and sunflower. A total of 164 crosses putatively combining Lr10 and Lr21, 191 crosses combining Lr10 and Lr34, and 201 crosses putatively combining Lr21 and Lr34 are now complete for wheat. A graduate student is validating the pyramided combinations in wheat using the appropriate Lr gene markers, and pyramided genotypes are being inoculated with non-host specific oat crown rust to help assess the cost of host resistance in the near-isogenic wheat lines. A second graduate student is treating a lesion mutant of wheat (Ning 7840) with allopurinol to attempt to inhibit lesion formation. If the allopurinol inhibits lesion formation, a comparison of lesion-forming and non-lesion forming plants is expected to simulate resistant and non-resistant plants, and thus, provide an estimate of the cost of resistance. PARTICIPANTS: Drs. William Berzonsky, Karl Glover, and Jose Gonzalez as well as Ms. Kathleen Grady served as project PIs. These PIs designed, directed, and provided oversight for the details of the research component of project. Additionally, as part of the teaching component, Dr. Berzonsky organized and taught PS 741 (Plant Breeding Techniques). Collaborators for the teaching portion included, Dr. Marcelo Carena, NDSU Corn Breeder and Dr. Brent Hulke, USDA-ARS Sunflower Breeder. Several breeders from Monsanto and Pioneer collaborated with Dr. Berzonsky in helping to teach PS 741. Ms. Christine Lubenow conducted project related research as a MS graduate student as did Mr. Thumbiko Mkandawire, who is a PhD graduate student. TARGET AUDIENCES: Both undergraduate and graduate students represented the target audience for PS741. The class combined formal learning and experiential learning from direct interactions with plant breeders. Skills which are not learned from textbooks were developed from "hands-on" demonstrations. These demonstrations included hybridizations for both cross and self-pollinated crops. Students also learned molecular techniques as applied to breeding, and how various plant breeding techniques are combined to rapidly develop new crop varieties. The research component mainly targeted graduate students. Graduate students were able to develop molecular genetic skills, plant breeding, and plant pathology skills as well as learn how to apply these techniques and skills to a practical variety development project. PROJECT MODIFICATIONS: Dr. Shaukat Ali was hired by SDSU as a cereal pathologist, and he will assume the project responsibilities of Dr. Jeff Stein, who left the employ of SDSU since the last reporting period.

Impacts
One outcome of the experiential learning that was fostered in PS741 is that students were able to acquire skills and learn breeding techniques that are applicable to both self and cross-pollinated crops. This results in more well-rounded students prepared to be next-generation plant breeders. For example, students learned the different skills needed to hybridize wheat, a self-pollinated crop, as well as the skills required to hybridize sunflower, a cross-pollinated crop. They also learned the different approaches and techniques being used by wheat compared with sunflower breeders to produce doubled-haploid breeding lines, even though the purpose of producing the doubled-haploid lines for both crops is essentially the same. Students learned that doubled-haploids are produced in wheat through wide-hybridization and chromosome elimination, whilst they are produced in sunflower from intra-specific hybridizations involving a haploid-inducing genotype. The sunflower technique is similar to a technique generally employed to produce doubled-haploids in corn. To validate the production of breeding lines, which we expect to have combined genes for Lr10, Lr21, and Lr34, lines were genotyped by a student supported by this NIFA project and by the USDA-ARS Genotyping Lab in Manhattan, KS. Several pyramided lines were identified, and these are expected to positively impact the transfer of new Lr genes to adapted breeding lines and varieties as well as help assess any fitness cost associated with pyramiding. We found that one published Lr21 molecular marker may also be indicative of Lr10, and we continue genotyping to confirm these results. If confirmed, the marker may have added utility in marker-assisted selection for resistance to leaf rust. Thatcher spring wheat genotypes with Lr21 and Lr34 and treated with crown rust generally expressed lower seed weight and produced fewer seeds compared with Thatcher genotypes with Lr21 and Lr34 and not treated with crown rust. This could be an indication that there is a cost to responding to exposure to even a non-specific rust pathogen.

Publications

• No publications reported this period

Progress 03/01/10 to 02/28/11

Outputs
OUTPUTS: Plant Breeding Techniques (PS741), a course established to partially achieve the education objective was taught for the second time. Eleven students were enrolled in the course, and two students were undergraduates. Students were provided the opportunity to interact with breeders and staff personnel working with both cross and self-pollinated crops, such as; corn, soybean, sunflower and wheat. Compared to the first year of the project and as a consequence of visiting Pioneer and Monsanto corn and soybean breeding programs, students were exposed to a more balanced perspective on public and private breeding programs. Examples of breeding programs and plant breeders who interacted with PS741 students included; the NDSU Corn Breeding Program (Fargo, ND), the USDA-ARS Sunflower Breeding Program (Fargo, ND), the Pioneer Soybean Breeding Program (Volga, SD) and the Monsanto Corn and Soybean Breeding Programs (Harrisburg, SD). Hybridizations were made to pyramid host leaf rust genes in both wheat and sunflower. A total of 164 crosses putatively combining Lr10 and Lr21, 191 crosses combining Lr10 and Lr34, and 201 crosses putatively combining Lr21 and Lr34 are now complete for wheat. A graduate student is validating the pyramided combinations in wheat using the appropriate Lr gene markers, and pyramided genotypes are being inoculated with non-host specific oat crown rust to help assess the cost of host resistance in the near-isogenic wheat lines. We expect the crown rust to elicit a hypersensitive reaction in wheat plants, but not to cause the production of rust pustules. Five sunflower hybrids and three backcrosses were produced, and crosses are expected to carry R1, R4b, or R5 for resistance to leaf rust. PARTICIPANTS: Drs. William Berzonsky, Karl Glover, and Jose Gonzalez as well as Ms. Kathleen Grady served as project PIs. Dr. Jeff Stein left the employ of South Dakota State University and was removed as a project PI. The remaining PIs designed, directed, and provided oversight for the details of the research component of project. Additionally, as part of the teaching component, Dr. Berzonsky organized and taught PS 741 (Plant Breeding Techniques). Collaborators for the teaching portion included, Dr. Marcelo Carena, NDSU Corn Breeder and Dr. Brent Hulke, USDA-ARS Sunflower Breeder. Several breeders from Monsanto and Pioneer collaborated with Dr. Berzonsky in helping to teach PS 741. Ms. Christine Lubenow conducted project related research as a MS graduate student as did Mr. Thumbiko Mkandawire, who is a PhD graduate student. Mr. David Boehm of AgriPro Wheat, Dr. John Davies of WestBred, Dr. Marcelo Carena (NDSU), and Dr. Brent Hulke (USDA-ARS) served on the project Advisory Board and made teaching and research recommendations to Dr. Berzonsky. TARGET AUDIENCES: With the offering of PS 741, primarily graduate students, but also undergraduate students were targeted for formal classroom instruction in teaching the techniques and methods of plant breeding. This is a newly designed course, and for the first time, it was added to the curriculum in its present form as a result of the funded award. PS 741 features experiential learning, and as part of this effort, students benefited from learning breeding techniques and approaches to problems that are only learned from practice, and not from textbooks. Examples of the skills and techniques learned by students in PS 741 include; learning various crop hybridization techniques (for cross and self-pollinated crops), learning molecular techniques as applied to breeding, and learning how various plant breeding techniques are combined to rapidly develop new crop varieties. The research component mainly targeted graduate students. Graduate students were able to develop molecular genetic skills, plant breeding, and plant pathology skills as well as learn how to apply these techniques skills to a practical variety development project. PROJECT MODIFICATIONS: Dr. Jeff Stein left the employ of South Dakota State University and has been removed as a PI for the project. In 2012, new faculty Cereal Research Pathologist, Dr. Shaukat Ali is expect to support the project in the the capacity Dr. Stein once did.

Impacts
An outcome of the PS741 experiential learning is that students began to comprehend nuances of breeding programs that are otherwise not understood from reading textbooks. Because they were able to compare their experiences between public and private breeding programs, students recognized important differences. As an example, students learned that there is substantial collaboration between all soybean breeding programs within Pioneer, regardless of their physical proximity. The strength of this approach is that the interchange of germplasm enables the company to maintain a broader genetic base, which consequently, helps sustain genetic gain within their breeding programs. A major difference students also recognized between public and private breeding programs is that private programs follow a rigid schedule of standard operating procedures compared with public programs. Such rigidity results in the most efficient use of resources, but it also limits the ability of the breeder to rapidly change breeding approaches in response to emerging producer problems. In pyramiding genes for resistance to leaf rust in wheat, we realized testing for the cost of resistance would be difficult if we utilized virulent, race-specific leaf rust pathogens to produce incompatible host reactions to disease. Consequently, an important outcome was developing a non-host, race non-specific model to test for host resistance. Genotypes with different pyramided host leaf rust gene combinations have been produced. These are expected to be invaluable in impacting assessments of pyramiding genes for resistance, and ultimately, they will help breeders determine the value of taking this approach to develop wheat and sunflower genotypes with more durable disease resistance.

Publications

• Berzonsky, W.A., K.D. Glover, J.L. Gonzalez-Hernandez, and K.A. Grady. 2012. Assessing the cost to pyramiding host resistance to biotic stress in crop species. Poster presentation, USDA-NIFA Project Director Meeting, Jan. 14, preceding PAG XX Meetings, Jan. 14-18, San Diego, CA.
• Berzonsky, W.A., K.D. Glover, J.L. Gonzalez-Hernandez, K.A. Grady, and J.M. Stein. 2011. Assessing the cost to pyramiding host resistance to biotic stress in crop species. Poster presentation, USDA-NIFA Project Director Meeting, Jan. 14, preceding PAG XIX Meetings, Jan. 15-19, San Diego, CA.