Allelic Variation in TaMFT-3A is Associated with Seed Dormancy/Germination in Winter Wheat

The ability of viable seed to germinate under favorable environmental regimes is critical for seedling emergence, plant establishment, and subsequent development and growth of adult plants. This ability is controlled by internal factors (e.g., seed dormancy and hormones) and external factors (e.g., temperature and water). Winter wheat in the southern Great Plains is often planted six weeks before the optimal planting date to produce more wheat biomass as forage for cattle to graze during the following winter season. High germinability in the presence of high soil temperature is required to adapt to this specific management system. In a recent study, TaMFT-3A, mother of FT (FLOWERING LOCUS T) and TFT1 (TERMINAL FLOWER1) genes on chromosome 3A, was reported to regulate dormancy of seed in spring wheat cultivar Chinese Spring. We found TaMFT-3A was also tightly associated with the peak of a QTL for temperature-sensitive germination that segregated in the RIL population generated from two winter wheat cultivars; however, allelic variation in TaMFT-3A between the two winter wheat cultivars differed from that observed in spring wheat cultivars. These findings suggest that TaMFT-3A may invoke different mechanisms for controlling seed dormancy/germination among diverse wheat cultivars.