An example of dioecious plant is

A dioecious plant is a plant which has separate male and female plant. Cycas plants are dioecious. The male and female plant has cones which bear naked seed. The leaves are modified into cones. Microspores and megaspores are typically produced in pollen cones or ovulate cones, respectively in separate plants. Gametophytes, as with all heterosporous plants, develop within the spore wall. Pollen grains (microgametophytes) mature from microspores and ultimately produce sperm cells. Megagametophytes develop from megaspores and are retained within the ovule.