Potential agronomic and physiological traits of Spanish groundnut varieties (Arachis hypogaea L.) as selection criteria under end-of-cycle drought conditions

Groundnut grown in the SaheI is often exposed to end-of-season drought. The aim of this study was to identify traits associated with yield variation during end-of-cycle water deficit, which could be used as selection criteria. Five new selected Spanish varieties (80-90 days) were compared with the check cultivar, 55-437. Earliness and general adaptation of the varieties did not impair the expression of significant genetic variation for some traits relative to flowering, productivity and physiology. The partitioning coefficient (p) and yield under water stress conditions of the five varieties were higher than those of cultivar 55-437. The water deficit affected leaf area index, relative water content and transpiration at about 2 weeks after the occurrence of water deficit at the soil level. Since genotypic differences seemed to be greatest at this time, measuring physiological traits during this period may provide useful information for breeding early groundnut varieties under end-of-season water deficit conditions. (Résumé d'auteur