potato

Potatoes planted early, in March or April, can be ready for harvesting by late June. Commercially-grown potatoes are mechanically harvested. The same machine digs the potatoes out of the ground, cleans them of most of the dirt, then carries them by means of conveyor chains up to a grading table, where they are cleaned and sorted by hand before being loaded into a truck.

Perennial plant with edible tuberous roots that are rich in starch and are extensively eaten as a vegetable. Used by the Andean Indians for at least 2,000 years before the Spanish Conquest, the potato was introduced to Europe by the mid-16th century, and reputedly to England by the explorer Walter Raleigh. (Genus Solanum tuberosum, family Solanaceae.)

In Ireland, the potato famine of 1845, caused by a parasitic fungus, resulted in many thousands of deaths from starvation, and led to large-scale emigration to the USA.

See also sweet potato under yam.

A potato genetically engineered to produce its own pesticide was developed in 1995. Researchers added the gene for Bt toxin, a natural pesticide produced by a soil bacterium, into a potato plant. The plant now produces Bt within its leaves. Bt is one of the safest pesticides available - it leaves many beneficial insects unharmed, and breaks down quickly in the environment without leaving a harmful residue - but some scientists fear the commercial growth of this potato will lead to increased pesticide resistance.