iTAG: Interactive laboratory exercises to explore genotype and phenotype using Oregon Wolfe barley

Authors: Wise, Roger; Fuerst, Gregory; PETERS, NICK - Iowa State University; BOURY, NANCY - Iowa State University; MCGHEE, LAURIE - Colfax-Mingo High School; GREENE, MELISSA - Albia Community School District; MICHAELSON, SARAH - Lake Forest Academy; GONZALEZ, JULIE - Des Moines Area Community College (DMACC); HAYES, NICK - Cedar Rapids Kennedy High School; SCHUCK, RON - Ames Community High School; MAFFIN, LANCE - Bondurant-Farrar High School; HALL, GARRETT - Burr And Burton Academy; HUBBARD, TAYLOR - Ankeny High School; WHIGHAM, EHREN - Creighton University

Submitted to: The Plant Health Instructor
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/21/2024
Publication Date: 5/9/2024
Citation: Wise, R.P., Fuerst, G.S., Peters, N., Boury, N., McGhee, L., Greene, M., Michaelson, S., Gonzalez, J., Hayes, N., Schuck, R., Maffin, L., Hall, G., Hubbard, T., Whigham, E. 2024. iTAG: Interactive laboratory exercises to explore genotype and phenotype using Oregon Wolfe barley. The Plant Health Instructor. 24. https://doi.org/10.1094/PHI-E-2023-09-0009.
DOI: https://doi.org/10.1094/PHI-E-2023-09-0009

Interpretive Summary: Most young people decide to pursue STEM careers in secondary school rather than college. Thus, there is a need to help these students, and their teachers, better understand the important impact and satisfaction that comes from “doing good science”. One of the basic concepts in biology is that an organism’s physical traits are controlled by genes that are encoded in DNA. In other words, one’s genotype for a particular trait controls the phenotype that is expressed. Students and novice researchers often struggle understanding this connection between DNA and physical characteristic. To address this challenge, we have created an inquiry-based curriculum of lab and classroom activities to make the connection from genotype to phenotype, a core foundation for modern genomics. This curriculum is designated “Inheritance of Traits and Genes” (iTAG) barley. iTAG uses the Oregon Wolfe Barley (OWB) population, a model resource for genetics research and instruction, to connect visible traits (phenotype) to identifiable differences in DNA sequence of genes. The curriculum demonstrated here focuses on three traits to illustrate concepts in plant development, domestication, and disease resistance. Students learn basic molecular biology techniques of DNA extraction, polymerase chain reaction, and gel electrophoresis and document DNA polymorphisms among plants with different phenotypes. Teachers can then lead a discussion of cosegregation and how researchers associate genotype and phenotype. Impact: Utilization of state-of-the-art genomic resources to their full potential requires a well-educated and well-trained research workforce. To promote USDA Strategic Goal 6, we have established iTAG barley, an NSF and NIFA-funded Research Experience for Teachers (RET), using the diverse Oregon Wolfe Barley population as the model. iTAG "Inheritance of Traits and Genes”, connects plant pathology, microbiology, genetics and development with active learning exercises that teachers train as summer RETs, and then engage with their students during the school year to illustrate how doing good science impacts food security.

Technical Abstract: One of the basic concepts in biology is that an organism’s physical traits are controlled by genes that are encoded in DNA. In other words, one’s genotype for a particular trait controls the phenotype that is expressed. Students and novice researchers often struggle understanding this connection between DNA and physical characteristic. “Inheritance of Traits and Genes” (iTAG) uses the Oregon Wolfe Barley population (OWB) in a series of laboratory and classroom activities designed to connect visible traits (phenotype) to identifiable differences in DNA sequence of genes. This workbook focuses on three traits to illustrate basic concepts in plant development, domestication, and disease resistance. Using the iTAG Barley module, students can observe the OWB spikes for seed-coat color, two row vs. six row (encoded by Vrs1, a domestication trait), hooded vs. non-hooded (encoded by BKn3 - a homoeotic mutation where the awn is replaced by a duplicate spikelet), and long awn vs. short awn (encoded by Lks2). Lastly, the OWB population segregates for resistance or susceptibility to powdery mildew disease, due to different alleles of Mildew locus a (Mla). Students will learn basic molecular biology techniques of DNA extraction, polymerase chain reaction, and gel electrophoresis and document DNA polymorphisms among plants with different phenotypes. Teachers can then lead a discussion of cosegregation and how researchers associate genotype and phenotype.