Wild, edible plants -- many rich in vitamin A-producing beta-carotene -- play an important role in the diet of Burkina Fasoand may be preventing a certain type of blindness in parts of that small, drought-prone country of northwestern Africa, according to a UC Davis researcher. "Wild plants, most of them vine leaves used in sauces and soups, compose about one-third of the diet in southern Burkina Faso," says Garrett C. Smith, a doctoral candidate in geography. In contrast, people of the arid north have much less access to wild, edible plants and are significantly more vulnerable to a form of blindness caused by nutritional deficiencies, says Smith. During a six-month visit to Burkina Faso last year, he conducted a survey to identify environmental and cultural factors that influence dietary use of wild plants. After a nutritional analysis of many of the wild plants from the south, Smith hopes to recommend to Burkina Faso officials those plants that should be planted in the north to prevent malnutrition. Smith will present his work at 10:20 a.m. Wednesday, March 30.