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百岁兰(Welwitschia mirabilis)又称百岁叶、千岁兰等,是世界上叶片寿命最长的植物,属于裸子植物百岁兰科而非兰花,本科植物仅此一种,原产于非洲东南部热带沙漠,我国深圳仙湖植物园、北京植物园都有栽培。百岁兰为多年生木本植物,长可达4m高的粗大的茎杆,露出地面仅20cm左右。茎可逐年增粗,茎下部有粗大的直根。茎顶一生只长出两片叶,初生的叶片质地柔软,以后逐渐
Welwitschia mirabilis, also known as centenarians and centenarians, are the longest life-spanning plants in the world and belong to the class of gymnosperms rather than to orchids. Only one undergraduate plant is native to southeastern Africa Ministry of tropical desert, China’s Shenzhen Lake Botanical Garden, Beijing Botanical Garden have cultivated. Centenarian blue perennial woody plants, up to 4m tall, thick stems, exposing only about 20cm on the ground. Stems can be thicker year by year, the stem has a thick root straight roots. Stem top grow only two leaves of life, newborn leaves texture soft, gradually after