图2. 短日照条件下幼穗分化发育进程
A：出苗后7 d,生长点伸长期;B：出苗后8 d,穗枝梗原基分化期,一级枝梗原基分化;C：出苗后9 d,穗枝梗原基分化期,二级枝梗原基分化;D：出苗后12 d,小穗原基分化期,出现护颖原基;E：出苗后13 d,小花原基分化期,第一朵小花分化;F：出苗后14 d,小花原基分化期,第二朵小花分化;G：出苗后17 d,雌雄蕊原基分化期,花粉母细胞形成;H：出苗后18 d,雌雄蕊原基分化期,花粉母细胞减数分裂;I：出苗后21 d,花粉粒形成期

Fig. 2. The development process of panicles under short-day condition
A: 7 DAE (days after seedling emergence). Elongation period of growth point; B: 8 DAE. Differentiation stage of panicle branch primordia, primordia differentiation of primary branches; C: 9DAE. Differentiation stage of panicle branch primordia, primordia differentiation of secondary branches; D:12 DAE. Spikelet primordia differentiation period, glume protection primordia appeared; E: 13 DAE. Spikelet primordia differentiation period, differentiation of the first floret; F: 14 DAE. Spikelet primordia differentiation period, differentiation of the second floret; G: 17 DAE. Pistil and stamen primordium differentiation stage, pollen mother cell formation; H:18 DAE. Pistil and stamen primordium differentiation stage, meiosis of pollen mother cells; I: 21 DAE. Pollen grain formation stage