山药属薯蓣科,薯蓣属植物。草质缠绕藤本,茎左旋,单叶互生,盾形,叶面常有不规则斑块状的灰白条纹,边缘浅波状,基部心形。花雌雄异株或同株,雄花序穗状,3～6朵簇生,花被紫红色,雌花序总状穗状。蒴果三棱,干枯后呈黄褐色。种子褐色,尾部着生膜状翅1片。山药食用部分为块茎,主要含 Yam is Dioscoreaceae, Dioscorea. Grass winding entomology, stem levorotatory, single leaf alternate, shield-shaped, leaf surface often irregular plaque gray stripes, the edge of shallow wavy, base of the heart-shaped. Flowers dioecious or the same strain, male inflorescence spikes, 3 to 6 clusters of flowers, perianth purple, female inflorescences racemose. Capsule Triangular, dry brown color. Seeds brown, the tail with a membranous membranous wings. Yam edible part of the tubers, mainly containing