Identifying the physiological and genetic traits related to drought tolerance in cassava - 2006.

Cassava (Manihot esculenta Crantz) is one of the most important staple foods in the human diet in the tropics, cultivated in areas considered marginal for other crops. Because of its remarkable tolerance to drought and great ability to survive uncertain rainfall patterns, it is considered a contributor to food-security against famine, requiring minimal inputs and making it an important crop for drought prone areas of tropical and sub-tropical Africa, Asia and Latin America. When water is available, cassava maintains a high stomatal conductance with high internal CO2 concentration; but when water becomes limiting, the stomata are closed in response to even small decreases in soil water potential. In addition, leaf area growth is decreased in response to water stress and is rapidly reversed following the release from stress. This suggests that the ability to regulate numerous plant processes to rapidly change course is the key for cassava success unfavorable weather. This project aims to determine the best traits to be used in breeding programs for drought tolerance by elucidating the mechanisms of cassava’s remarkable tolerance to drought and to identify trait-marker associations for the development of a more costeffective breeding process for drought tolerance that can be used for cassava and other crops.