Morpho-physiological traits contributing to water stress tolerance in a peanut (Arachis hypogaea L.) landraces collection from the Algerian Maghreb

To explore the relationships between morpho-physiological traits and drought tolerance, we evaluated here the response to water stress exhibited by a collection of peanut (Arachis hypogaea L.) landraces traditionally grown in different climatic regions of the Algerian Maghreb. Upon applying a multivariate statistical approach to the data obtained from water-stressed plants, two components were identified: 1) the 'root vigour', associated to a long root system, exhibiting both deep and laterally spreading rooting pattern, abundant N-2-fixing nodules, and pronounced stem growth; 2) the 'above-ground physiological mechanisms', associated to the ability to maintain greener leaves and cooler canopy temperature, via permissive values of leaf water potential allowing a certain degree of stomatal perviousness, even under conditions of severe water stress. On such bases, it became possible to identify a subgroup of peanut landraces which could be considered as parental lines in breeding programs for those cultivation environments facing endemic water shortage.