野鸢尾种子至种苗的发育形态学

摘要

An experiment was conducted to observe the development process from seed to seedling of Iris dichotoma. Results showed that the shoot ends developed earlier than the root ends in seed embryo. When the seeds germinated, the hypocot-yls appeared firstly and swelled around the end of it, and some hairs (hypocotyl hair) arose from the swelling. Embryo was triangular in seed embryo, and then embryo developed into a tongue shape and swelled after a time. At last, embryo broke out of cotyledonary sheath into air. The development process of /. Dichotoma seedlings coincides with that of original aquatic macrophytes. /. Dichotoma may evolve from original aquatic plants.%追踪观察了野鸢尾从种子到种苗的发育过程.结果发现,种子胚苗端发育先于根端；萌发时首先出现下胚轴,继而根环处膨大产生下胚轴毛.种子胚时期,胚芽呈三角形,萌动一段时间后变为舌形,继而胚芽位置开始膨大,向外一侧的子叶鞘逐渐变薄,胚芽突破子叶鞘进入空气之中.野鸢尾可能是由原始水生植物进化来的,因为其种苗发育具有原始水生大型植物的特点.