Verticillium wilt of potato in central Peru

Studies in the 1950’s indicated thatVerticillium alboatrum was present in potato fields in the irrigated coastal valleys of central Peru. No further studies were carried out in Peru until those in the late 1970’s initiated at The International Potato Center. So far, Verticillium wilt of potatoes has been observed in several valleys of the coast as well as in highland valleys at elevations up to 3400 m. Although the frequency of isolation ofVerticillium sp. has been much greater in the highlands, the disease is of less consequence there because of low temperatures during the growing season. The most common symptom observed in the field is early senescence, including yellowing and stunting of the foliage. Typical “wilt” symptoms are rarely found. Both in the coastal valleys and in the highlands, onlyVerticillium dahliae has been identified. Although no studies on losses and the economic importance of Verticillium wilt of potatoes have been done, it is clear that the two most important crops used in rotation in coastal valleys of central Peru, potato and cotton, are severely affected.