Seed dormancy is an adaptive mechanism and an important agronomic trait. Temperature during seed development strongly affects seed dormancy in wheat (Triticum aestivum) with lower temperatures producing higher levels of seed dormancy. To identify genes important for seed dormancy, we used a wheat microarray to analyze gene expression in embryos from mature seeds grown at lower and higher temperatures. We found that a wheat homolog of MOTHER OF FT AND TFL1 (MFT) was upregulated after physiological maturity in dormant seeds grown at the lower temperature. In situ hybridization analysis indicated that MFT was exclusively expressed in the scutellum and coleorhiza. Mapping analysis showed that MFT on chromosome 3A (MFT-3A) colocalized with the seed dormancy quantitative trait locus (QTL) QPhs.ocs-3A.1. MFT-3A expression levels in a dormant cultivar used for the detection of the QTL were higher after physiological maturity; this increased expression correlated with a single nucleotide polymorphism in the promoter region. In a complementation analysis, high levels of MFT expression were correlated with a low germination index in T1 seeds. Furthermore, precocious germination of isolated immature embryos was suppressed by transient introduction of MFT driven by the maize (Zea mays) ubiquitin promoter. Taken together, these results suggest that MFT plays an important role in the regulation of germination in wheat.

We developed a method for determining nationwide 1 km-grid square values of daily mean, maximum and minimum air temperature, and daily precipitation in Japan. The data were obtained using the JMA's nationwide observations, numerical forecasts, and climatic normal values. RMSE values for these elements in the past were 0.66 ℃, 0.98 ℃, 1.10 ℃, and 5.9 mm/day, while those for one-day future were 1.18 ℃, 1.65 ℃, 2.00 ℃, and 11.0 mm/day, respectively. The improvement in accuracy by introducing the forecasts was recognized even for values six-day future, though errors tended to increase with forecast range. The data are intended for use in the management of currently growing crops with a combination of crop models.

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Between 2002 and 2011, 3 varieties of wheat, 'Norin61' (spring type), 'Shirogane Komugi' (spring type), and 'Satonosora' (winter type), were grown in the upland and lowland fields in Tsukuba, Ibaraki Prefecture, Japan. Phenological development was divided into 5 phases: phase 1, sowing to emergence; phase 2, emergence to jointing; phase 3, jointing to heading; phase 4, heading to flowering; and phase 5, flowering to maturation. The duration of phase 2 varied with the sowing date and cultivar. In 'Satonosora', the jointing stage was later than that in the other cultivars in early sowing, but this difference diminished at late sowing. Phenological development was expressed using the developmental rate (DVR) and developmental index, which is the cumulative DVR. DVR was expressed as a function of daily mean temperature and photoperiod in phase 2, but as a function of temperature in the other phases. These models achieved a good fit for the jointing, heading, and maturity dates of each cultivar measured in a wide area in Japan, with root mean square error = 4-6 days. However, a simpler 2-phase model (sowing to heading and heading to maturation) could provide better estimates for the prediction of the jointing day alone.

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