Rice flowers after a lengthy vegetative growth. During the vegetative growth period flowering is inhibited by several independent pathways. Whereas Grain number, plant height, and heading date 7 (Ghd7), Heading date 1 (Hd1), Heading date 5 (Hd5), Heading date 6 (Hd6), and Heading date 16 (Hd16) preferentially function to delay flowering under long day conditions, Oryza sativa Phytochrome B (OsPhyB), Oryza sativa CONSTANS-like 4 (OsCOL4), SUPERNUMERARY BRACT (SNB) and Oryza sativa INDETERMINATE SPIKELET 1 (OsIDS1) independently inhibit flowering regardless of day length. After sufficient vegetative growth, flowering signals are produced in the leaves due to reduced expression of the inhibitors. In addition, Hd1 becomes a flowering promoter when the day length becomes shorter. Long-day specific activators OsMADS50 and OsDof12, and a constitutive activators Oryza sativa INDETERMINATE 1 (OsId1), Early heading date 4 (Ehd4), and miR172, are accumulated in the leaves when plants are grown sufficiently. Several circadian clock genes are also involved in floral transition, including Oryza sativa GIGANTEA (OsGI), Heading date 2 (Hd2), and Heading date 17 (Hd17). Floral transition is also controlled by photoreceptors and chromatin remodeling factors. Most of the upstream signals are transferred to Early heading date 1 (Ehd1) that is a positive regulator of Heading data 3a (Hd3a) and Rice FT 1 (RFT1), which are transferred to the shoot apical meristem to induce the reproductive transition.
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机译：水稻在长期营养生长后开花。在营养生长期中，开花受到多种独立途径的抑制。粒数，株高和抽穗期7（Ghd7），抽穗期1（Hd1），抽穗期5（Hd5），抽穗期6（Hd6）和抽穗期16（Hd16）优先用于延迟长时间开花在日间条件下，稻米植物色素B（OsPhyB），稻米CONSTANS-like 4（OsCOL4），超高BRACT（SNB）和稻米不确定性小穗1（OsIDS1）均能独立抑制开花，无论白天如何。在足够的营养生长后，由于抑制剂表达降低，在叶片中产生开花信号。另外，当日长度变短时，Hd1成为开花促进剂。当植物充分生长时，长日特异性激活因子OsMADS50和OsDof12以及组成型激活因子稻不定稻1（OsId1），早抽穗日期4（Ehd4）和miR172会累积在叶片中。一些昼夜节律时钟基因也参与花期转换，包括水稻（Osza sativa GIGANTEA）（OsGI），抽穗期2（Hd2）和抽穗期17（Hd17）。花的过渡也受感光器和染色质重塑因子控制。大多数上游信号被转移到早期抽穗日期1（Ehd1），这是抽穗数据3a（Hd3a）和Rice FT 1（RFT1）的正调节剂，它们被转移到茎尖分生组织以诱导生殖过渡。
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