Expression of cold tolerance and flowering time genes in perennial wheat

Wheat (Triticum aestivum) is either a spring or winter type annual, completing its lifecycle within one growing season or calendar year. Perennial plants are able to grow over multiple years as they often alternate between vegetative and reproductive phases. Availability of perennial wheat would be a valuable innovation in agriculture and would have many economic and environmental advantages. The development of perennial wheat has been attempted for many years by crossing wheat (Triticum spp.) with a close perennial relative, wheatgrass (Thinopyrum spp.). However, these perennial wheat lines are weakly perennial, generally dying before the second growing season. Our hypothesis is that perennial habit, as it relates to perennial wheat, is dependent on strict control in cycling between the vegetative and reproductive phases, which involves altering gene expression, and developing sufficient cold hardiness to successfully overwinter. To establish whether current perennial wheat lines are able to alternate efficiently between the vegetative and reproductive phases and if they can cold acclimate sufficiently in their second vegetative cycle, expression of cold tolerance and flowering time genes was examined. Gene expression was quantified in perennial wheat, annual wheat and wheatgrass lines grown under varying photoperiods and temperatures and transcripts were amplified using qPCR. Results on gene regulation of flowering time and cold tolerance genes will be presented and relationships between flowering time and cold tolerance genes, cold tolerance, and perennial habit will be discussed and related to perennial wheat development through breeding.