The role of seasonal flowering responses in adaptation of grasses to temperate climates.

Siri Fjellheim,Scott Boden,Ben Trevaskis

doi:10.3389/fpls.2014.00431

Abstract

Grasses of the subfamily Pooideae, including important cereal crops and pasture grasses, are widespread in temperate zones. Seasonal regulation of developmental transitions coordinates the life cycles of Pooideae with the passing seasons so that flowering and seed production coincide with favorable conditions in spring. This review examines the molecular pathways that control the seasonal flowering responses of Pooideae and how variation in the activity of genes controlling these pathways can adapt cereals or grasses to different climates and geographical regions. The possible evolutionary origins of the seasonal flowering responses of the Pooideae are discussed and key questions for future research highlighted. These include the need to develop a better understanding of the molecular basis for seasonal flowering in perennial Pooideae and in temperate grasses outside the core Pooideae group.

Highlights

OVERVIEW Grasses from the Pooideae subfamily, family Poaceae, occur widely in temperate regions (Hartley, 1973)
Adaptations that allow Pooid grasses to survive the seasonal extremes of temperate climates are of interest since these are central to the success of this sub-family across temperate zones
We will highlight how different seasonal cues can adjust the developmental program of grasses to match seasonal cycles, using temperate cereals as examples, and examine how naturally occurring variation in these responses drives adaptation to different geographical regions and climates

Summary

Introduction

OVERVIEW Grasses from the Pooideae subfamily, family Poaceae, occur widely in temperate regions (Hartley, 1973). Long-day induction of VRN1 via FT1 is unlikely to play a major role in triggering inflorescence initiation in response to vernalization, since VRN1 is expressed at high levels in leaves and at the shoot apex of vernalized plants irrespective of daylength (Sasani et al, 2009).

Results

Conclusion