"IT IS OF STRATEGIC IMPORTANCE FOR MEDITERRANEAN AGRICULTURE TO DEVELOP NEW VARIETIES OF DURUM WHEAT WITH GREATER PRODUCTION POTENTIAL, TOGETHER WITH A BETTER ADAPTATION TO ADVERSE ENVIRONMENTAL CONDITIONS AND BETTER QUALITY OF GRAIN. WHILE THAT HARD WHEAT IT HAS BENEFITED AS OTHER CEREALS OF THE GREEN REVOLUTION, GENETIC PROGRESS IN RECENT DECADES HAS BEEN LESS EVIDENT, PARTLY MASKED BY CLIMATE CHANGE, AND THE UNDERLYING MECHANISMS ARE NOT WELL KNOWN. WHILE A BETTER PHENOTYPING WILL HELP IN THE CURRENT IMPROVEMENT, A DEEPER UNDERSTANDING OF PLANT RESPONSES TO A WIDE RANGE OF MEDITERRANEAN CONDITIONS WILL CONTRIBUTE TO A LONG-TERM DESIGN OF GENOTYPES BEST SUITED IN TERMS OF PRODUCTION AND QUALITY. IN FACT, THESE ASPECTS ARE AMONG THE CURRENT LIMITATIONS THAT PREVENT ACCELERATING THE IMPROVEMENT OF CROPS. FOR THIS PURPOSE IT IS NECESSARY TO PROVIDE THE CURRENT BREEDING PROGRAMS WITH SELECTION CRITERIA AND HIGH CAPACITY METHODOLOGIES OF PHENOTYPING IN THE FIELD. SO THIS PROJECT HAS TWO MAIN OBJECTIVES: ONE OF BASIC RESEARCH AND OTHER LOOKING FOR MORE FINALISTIC MEASURES. 1) DEFINE / REFINE SELECTION CRITERIA. THE FIRST OBJECTIVE IS TO DEEPEN THE PHYSIOLOGICAL AND MOLECULAR MECHANISMS INVOLVED IN THE ADAPTIVE RESPONSE OF DURUM WHEAT ACROSS A WIDE RANGE OF ENVIRONMENTAL CONDITIONS. THE FIRST ACTION WILL CONSIST OF A ""RETROSPECTIVE STUDY"", WHERE A PANEL OF 20 SEMI-DWARF GENOTYPES (POST- GREEN REVOLUTION) OF DURUM WHEAT, MARKETED IN SPAIN OVER THE PAST FOUR DECADES, WILL BE STUDIED. THE PANEL WILL BE CULTIVATED UNDER CONDITIONS OF RAINFED AND SUPPLEMENTAL IRRIGATION AT THREE STATIONS IN A WIDE RANGE OF LATITUDES: TWO OF THE INIA (CORIA DEL RIO, SEVILLE AND COLMENAR DE OREJA, MADRID) AND THE OTHER OF ITA (STATION OF ZAMADUEÑAS, VALLADOLID). BESIDES AGRONOMIC COMPONENTS AND CROP PRODUCTIVITY, GROWTH AND WATER USE EFFICIENCY WILL BE ASSESSED BY REMOTE SENSING TECHNIQUES AT THE LEVEL OF PLOT, AND STABLE ISOTOPES OF CARBON (D13C) AND NITROGEN (D15N) IN DRY MATTER (LEAVES AND GRAINS). THE SECOND ACTION WILL CONSIST OF STUDYING THE INTERACTIONS AMONG HYDROLOGIC REGIME AND CO2 AND ITS EFFECT ON THE GROWTH, PHOTOSYNTHETIC/TRANSPIRATORY ACTIVITY, LEVELS OF METABOLITES AND GENE EXPRESSION OF THE LEAVES AND STEM. EXPERIMENTS WILL BE CONDUCTED IN CONTROLLED CONDITIONS OF GROWTH CHAMBER IN GENOTYPES WITH CONTRASTING RELEASE DATE. (2) PRACTICAL IMPLEMENTATION OF THE PHENOTYPING. CONSISTING OF SEVERAL ACTIONS: A) THE DEVELOPMENT AND EVALUATION OF A PLATFORM OF PHENOTYPING IN FIELD, BEING VERSATILE, WITH HIGH-CAPACITY AND MODERATE COST. THIS PLATFORM WILL CONSIST ON AN AERIAL VEHICLE AND ITS AUTOPILOT, CARRYING VISIBLE AND NEAR INFRARED THERMAL CAMERAS. THE IDEA IS TO CALIBRATE THE MEASURES OF THE PLATFORM AGAINST PERFORMANCE, SEMOLINA QUALITY AND REMOTE SENSING PARAMETERS SIMILAR TO THOSE OF THE PLATFORM BUT MEASURED ON GROUND OF FIELD TRIALS OF THE ""RETROSPECTIVE STUDY"". B) DEEPENING THE USE OF STABLE ISOTOPES (D13C, D15N, D18O AND D2H) FOR EVALUATION OF PERFORMANCE, AND SPECIFIC ASPECTS OF THE FUNCTIONALITY OF THE PLANT: I) ARCHITECTURE OF ROOTS, II) PHOTOSYNTHETIC CAPACITY OF THE SPIKE (IN COLLABORATION WITH CIMMYT) AND III) POST-ASSIMILATORY ALTERATIONS OF THE SIGNAL OF D18O AND D2H. "