图5. 百山祖冷杉种子及其胚与胚乳发育过程的形态结构
(A) 5月25日的胚珠; (B) 6月25日类型I种子的胚与胚乳; (C) 6月25日类型II种子的胚乳; (D) 5月25日胚珠的石蜡切片, 红色方框内为花粉(上)与颈卵器(下); (E) 6月25日类型I种子的石蜡切片, 红色方框内为胚; (F) 6月25日类型II种子的石蜡切片; (G) 7月25日类型I种子的胚与胚乳; (H) 7月25日类型II种子的胚乳; (I) 7月25日类型III种子内皱缩的胚乳或/和胚; (J) 7月25日类型I种子的石蜡切片, 红色方框内为胚; (K) 7月25日类型II种子的石蜡切片; (L) 7月25日类型III种子的石蜡切片; (M) 8月25日类型I种子的胚与胚乳; (N) 8月25日类型III种子; (O) 9月25日类型I种子的胚与胚乳。Bars=1 000 μm。MF: 珠孔; In: 珠被; Em: 胚; Es: 胚乳; Po: 花粉; FG: 雌配子体; Re: 树脂囊; Ext: 外种皮; Ent: 内种皮; Cy: 子叶; Hy: 下胚轴; Su: 胚柄系统; ST: 皱缩组织; ER: 胚根; CC: 腐蚀腔

Figure 5. Morphology of Abies beshanzuensis seed and its embryo and endosperm during development
(A) The ovule on May 25th; (B) The embryo and endosperm of type I seeds on June 25th; (C) The endosperm of type II seeds on June 25th; (D) The paraffin section of the ovule on May 25th, the pollen (top) and archegonium (bottom) are in the red box; (E) The paraffin section of type I seeds on June 25th, the embryo in the red box; (F) The paraffin section of type II seeds on June 25th; (G) The embryo and endosperm of type I seeds on July 25th; (H) The endosperm of type II seeds on July 25th; (I) The shriveled tissue of endosperm or/and embryo within type III seeds on July 25th; (J) The paraffin section of type I seeds on July 25th, the embryo in the red box; (K) The paraffin section of type II seeds on July 25th; (L) The paraffin section of type III seeds on July 25th; (M) The embryo and endosperm of type I seeds on August 25th; (N) Type III seeds on August 25th; (O) The embryo and endosperm of type I seeds on September 25th. Bars=1 000 μm. MF: Micropylar funnel; In: Integument; Em: Embryo; Es: Endosperm; Po: Pollen; FG: Female gametophyte; Re: Resinocyst; Ext: Exotesta; Ent: Endotesta; Cy: Cotyledon; Hy: Hypocotyl; Su: Suspensor system; ST: Shriveled tissue; ER: Embryo root; CC: Corrosion cavity