Speakers: Loretta Johnson, PhD

Loretta Johnson, PhD

Professor of Biology
Kansas State University

 

Loretta Johnson is a Professor of Biology at Kansas State University. She studies the integrative field of ecological genomics, which seeks to link genomics, evolution and ecology to better understand plant adaptation to changing environments.

 

Taking Genomics Outdoors in the Great Plains: Linking Local Adaptation, Trait Variation, and Gene Expression of Perennial Grass Ecotypes in Prairies Across a Natural and Experimental Precipitation Gradient

Understanding drought tolerance is crucial for enhancing plant growth and ultimately ecosystem productivity. We investigate gene expression and ecological traits of wet and dry perennial grass ecotypes of a dominant forage grass Andropogon gerardi cross-transplanted across a rainfall gradient from Colby KS to Illinois and in response to drought using rainout shelters. This novel reciprocal garden platform is set in a realistic ecological community has been in place for a decade allowing interactions to play out on ecological timescales appropriate for long-lived perennial grasses. The study highlights the power of linking gene expression to phenotypic traits to unravel complex mechanisms of adaptation and ecotypic variation. By integrating ecological traits with gene expression, we identified genes that co-expressed with biomass, height, photosynthesis, and flowering—traits that influence success in ecological communities. These findings reveal candidate genes that drive local adaptation to rainfall, shedding light on trade-offs between stress tolerance and competitive ability in dry and wet ecotypes, respectively. By identifying genetic targets linked to traits, climate-matched breeding will help ensure the long-term persistence of a foundation grass in a changing climate and will provide a foundation for ecologically informed restoration.