Testify A New Soybean Model Of Photo-Thermal Interaction And Clone FT Family Genes

Soybean, one of main plant proteins and lipid resources, plays an important role in our national agricultural production, with its plant area ranks top in four oil crops. As a short-day and temperature-bias plant, Soybean variety is sensitive to photoperiod and temperature, which account for its narrow plant area. Past study showed that productive growth of soybean could be accelerated by short day and high temperature, whereas, long day and low temperature slow it. Based on previous studies of predecessors and combined study result of ourself, we proposed a new model of Photo-Thermal Interaction in soybean, which can be simply described as that photoperiod determinates development direction while temperature determinates development progress. However, this model needs to be tested and fulfilled further.Depending on experimental system established with photoperiod-sensitive cultivar Zigongdongdou, combined with temperature treatments, we designed 10 different photoperiod and temperature treatments. Experimental results suggested that (1)The four treatments by short day flowered normally, and showed an apparent order, which, in turn, was the SD30℃,SD20℃-SD30℃, SD30℃-SD20℃and SD20℃. The plant height is greatly different when flowering, in spite of the same growth stage.(2)Flower reversion occurred after treated in short day for some time, and then transferred into long-day condition. The four reversion rates in reversion treatments from high to low are SD30℃-LD20℃, SD30℃-LD30℃, SD20℃-LD20℃and SD20℃-LD30℃.(3)The plants under treatments in long day, LD20℃and LD30℃, did not flower in the duration. All these results successfully explained the new model of Photo-Thermal Interaction in soybean and illumilated that photoperiod was the critical determinant factor of Soybean growth and development, whereas temperature determinated its vegetative growth speed.FT family genes play an extremely important role in the control of flowering. New study showed that FT mRNA might play an flowering role, it might be florigen, which produced in leaves and be transducted to shoot apex through phloem to regulate flowering. In...