According to the German weather forecast a rainy weekend seems to lie ahead of us. Perhaps, you find some time to brood over potatoes, one of the staple foods of the world. The potato (Solanum tuberosum) is an herbaceous annual that grows up to 100 cm (40 inches) tall and produces a tuber - also called potato - so rich in starch that it ranks as the world’s fourth most important food crop, after maize, wheat and rice. The potato belongs to the Solanaceae - or “nightshade”- family of flowering plants, and shares the genus Solanum with at least 1,000 other species, including tomato and eggplant. S. tuberosum is divided into two, only slightly different, subspecies: andigena, which is adapted to short day conditions and is mainly grown in the Andes, and tuberosum, the potato now cultivated around the world, which is believed to be descended from a small introduction to Europe of andigena potatoes that later adapted to longer day lengths.

  Potato world1991    1993    1995    1997    1999    2001    2003    2005    2007Countries    million tonnesDeveloped    183.13    199.31    177.47    174.63    165.93    166.94    160.97    159.99    155.56Developing    84.86    101.95    108.50    128.72    135.15    145.92    152.11    160.12    165.15WORLD    257.25    301.27    285.97    303.36    301.08    312.86    313.09    320.11    320.71Source: FAOSTAT