THE POTATO PLANT

Potato, or Solanum tuberosum, is an upright, herbaceous, perennial, tuberous plant that belongs to the Solanaceae family. It originates from Central and South America, but nowadays it is widely naturalized. The plant can grow up to 0.6-1 m in height.

The stems can be either quadrangular or winged, with bulbiferous stolons near or below the surface of the ground.

The leaves are alternate, imparipinnate, about 10–30 cm long and 5–15 cm broad. The leaflets are alternate or opposite, different in shape and size. The leaves perish after the plant blooms, produces fruits and forms tubers.

The flowers can be white, purple, blue, pink or red. They grow in compound umbels, the hairy peduncle reaches up to 5–15 cm in length, the jointed pubescent pedicels are about 3–35 mm long. The calyx is campanulate, 5-lobate, about 2 cm across; the corolla is about 3.5 cm in diameter; the anthers are yellow.

The fruit is a spherical or ovoid, yellowish green, 2-celled berry. It is similar to a green cherry tomato and consists of many seeds. The fruit is uneatable as it contains a toxic substance - alkaloid solanine. The plant can be propagated either from seeds, or from tubers.

The tubers can be globose or ovoid. Actually, they are swellings of the rhizome. The flesh of the tubers may vary in color – it can be white, blue, yellow. The color of the tuber skin can also be different (white, yellow, tawny, red and even blue). The flesh color not necessarily corresponds to the color of the skin. There are axillary buds with scars of scale leaves on the surface of the tubers. These buds are referred to as eyes. When the tubers are planted, the eyes begin to develop into stems in order to form a new plant.

Interesting Facts About Potato Tubers

• A potato tuber consists of about 80 % water and 20 % solids.
• They are absolutely gluten-free.
• Potatoes are the first vegetables that have been grown in space.
• China is the world’s biggest producer of potatoes.
• Potatoes are the fourth most important crops in the world (after wheat, corn and rice).
• One potato contains more vitamin C than an orange, more fiber than an apple and more potassium than one banana.

Chemical Composition of Potato Tubers

On average, a potato tuber contains 75% of water; 18,2% of  starch; 2 % of nitrogenous matters (crude protein); 1.5 % of sugars; 1 % of fiber; 0.1 % of fat; 0,2 % of titratable acids; 0.1 % of substances having phenolic nature; 0.6 % of pectin; 1.6 % of other organic compounds (nucleic acids, glycoalkaloids, hemicellulose etc.); 1.1 % of mineral substances.

Potato flowers contain much more poisonous alkaloid - solanine, than the shoots do. Apart from poison, the flowers contain some useful substances - flavonoids which strengthen blood vessels and slow down the aging processes in the body.