Renewable energy

Ecology

Programming language

Local adaptation

Environmental gradient

Population

Neuroscience

Biology

Gene

Trait

Panicum virgatum

Demography

Computer science

Outcrossing

Habitat

Sociology

Adaptation (eye)

Bioenergy

Pollen

Genetics

Quantitative trait locus

Proceedings of the National Academy of Sciences

Local adaptation is the process by which natural selection drives adaptive phenotypic divergence across environmental gradients. Theory suggests that local adaptation results from genetic trade-offs at individual genetic loci, where adaptation to one set of environmental conditions results in a cost to fitness in alternative environments. However, the degree to which there are costs associated with local adaptation is poorly understood because most of these experiments rely on two-site reciprocal transplant experiments. Here, we quantify the benefits and costs of locally adaptive loci across 17° of latitude in a four-grandparent outbred mapping population in outcrossing switchgrass ( Panicum virgatum L.), an emerging biofuel crop and dominant tallgrass species. We conducted quantitative trait locus (QTL) mapping across 10 sites, ranging from Texas to South Dakota. This analysis revealed that beneficial biomass (fitness) QTL generally incur minimal costs when transplanted to other field sites distributed over a large climatic gradient over the 2 y of our study. Therefore, locally advantageous alleles could potentially be combined across multiple loci through breeding to create high-yielding regionally adapted cultivars.

QTL × environment interactions underlie adaptive divergence in switchgrass across a large latitudinal gradient