The increasing demand for improved agricultural production will require more efficient breeding for traits that maintain yield under heterogeneous environments. The internal circadian oscillator is essential for perceiving and coordinating environmental cues such as day length, temperature, and abiotic stress responses within physiological processes. To investigate the contribution of the circadian clock to local adaptability, we have analyzed circadian period by leaf movement in natural populations of Mimulus guttatus and domesticated cultivars of Glycine max. We detected consistent variation in circadian period along a latitudinal gradient in annual populations of the wild plant and the selectively bred crop, and this provides novel evidence of natural and artificial selection for circadian performance. These findings provide new support that the circadian clock acts as a central regulator of plant adaptability and further highlight the potential of applying circadian clock gene variation to marker-assisted breeding programs in crops.
Bibliographical noteFunding Information:
This work was supported by grants from the National Science Foundation to K.G. (IOS-1202779), J.R.P. (IOS-1202778), and C.R.M, (IOS-0923752 and IOS-1025965) and by a grant from the NSF LiT to J.H.W. (IOS-1024966). We thank Monsanto Company for providing the soybean cultivars and Miya Howell, Shunhong Dai, and Sasha Preuss for helpful discussions.
- Circadian period
- Leaf movement
- Natural variation
- Selective breeding