Discipline: Biological Sciences
Subcategory: Plant Research
Session: 2
Room: Exhibit Hall
Anaya Arnold - Fort Valley State University
Co-Author(s): Hallie Wright, Katrien Devos, Institute of Plant Breeding, Genetics and Genomics, University of Georgia, Athens, GA 30602, USA
Pearl millet (Cenchrus americanus) is a diploid crop grown for its tolerance to harsh, warm climates and its high grain nutrient content. It is a highly nutritious cereal crop that is consumed by humans and forage by livestock that can withstand semi-arid regions where crops often fail. At least four dwarfing genes have been observed in pearl millet, including D4. The D4 mutants are extreme dwarfs and have low seed yield. The wild-type (tall) pearl millet lines experience lodging, resulting in preharvest yield loss. In mapping d4, the Devos lab observed that d4 mutants coupled with long bristles on pearl millet panicles exhibit an intermediate height. An intermediate height is beneficial for farmers because such lines would not experience lodging not extreme dwarfism, resulting in an adequate seed yield. The Devos’s lab has cloned the d4 gene, but to better understand the interaction between d4 and Br1, we identified the informative recombinant plants from an F2 mapping population segregating for panicle bristle length using already established markers which flank the gene and created and tested new molecular markers to narrow down the interval the Br1 gene lies. To do this, 264 F2 progeny from a bi-parental mapping population segregating for panicle bristle length were genotyped using High Resolution Melting Curve Analysis (HRMCA) for IGV9 and XIPES126 genotypes. The progeny which has different genotype scores for IGV9 and XIPES126 are classified as informative recombinants. These informative recombinants were then genotyped with new markers using HRMCA to further fine-map Br1. From this work, we have determined that the current interval harboring Br1 lies between markers 3980b and IGV9. We used a comparative data with a close relative, Setaria italica, of which the Br1 lies in a 29.6Mb interval. In the future, we plan to screen mapping population for additional informative recombinants and create new markers to continue narrowing down the Br1 interval and look for candidate genes in the region.
Funder Acknowledgement(s): The Rising Scholars Program through University of Georgia.
Faculty Advisor: Sarwan Dhir, dhirs0@fvsu.edu
Role: During my research, I identified the informative recombinant plants from an F2 mapping population segregating for panicle bristle length using already established markers which flank the gene. Also, I created and tested new molecular markers to narrow down the interval where the Br1 gene lies.