Sweet potato
The sweet potato is a dicotyledonous plant that belongs to the family Convolvulaceae
Convolvulaceae, known commonly as the bindweed or morning glory family, are a group of about 60 genera and more than 1,650 species of mostly herbaceous vines, but also trees, shrubs and herbs.- Description :...

. Its large, starch
Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...

y, sweet-tasting, tuberous roots are an important root vegetable
Root vegetable
Root vegetables are plant roots used as vegetables. Here "root" means any underground part of a plant.Root vegetables are generally storage organs, enlarged to store energy in the form of carbohydrates. They differ in the concentration and the balance between sugars, starches, and other types of...

. The young leaves and shoots are sometimes eaten as greens. Of the approximately 50 genera and more than 1,000 species of Convolvulaceae, I. batatas is the only crop plant of major importance—some others are used locally, but many are actually poisonous.