English: Potato (Solanum tuberosum L., 1753) of the genus Solanum (L., 1753) of the family Solanaceae (Juss., nom. cons., 1789) is a widespread agricultural crop. The major cultivars are autotetraploid subspecies. There are two major subspecies of Solanum tuberosum: andigena, or Andean; and tuberosum, or Chilean. The Andean potato is adapted to the short-day conditions prevalent in the mountainous equatorial and tropical regions where it originated; the Chilean potato, however, native to the Chiloé Archipelago, is adapted to the long-day conditions prevalent in the higher latitude region of southern Chile. It is grown for the tubers that form on underground stolons. Some writers define the term "tuber" to mean only structures derived from stems; others use the term for structures derived from stems or roots. Fruits are berries, similar to small tomatoes. Contains the poison solanine. The concentration of poison in the flesh of the tuber is low, in the skin and eyes is higher, in the berries - even higher.

Phytophthora infestans (Mont.) De Bary from the genus Phytophthora de Bary 1876 family Peronosporaceae.

A very harmful microscopic organism that can attack potatoes and destroy them completely: the potatoes become rotten and inedible. The species was brought to Europe from America with a cargo of potatoes in the early 1840s. It can also infect tomatoes and some other types of nightshade. Phytophthora affects all varieties of potatoes, and none of the varieties has complete resistance to all races of the pest. Biological features of the parasite are manifested in the ability to affect almost all plant organs: stems, leaves, inflorescences, tubers.

English: Potatoes sick with late blight.