SHORT-LIVED ISOTOPE TECHNOLOGY FOR EVALUATING PLANT GENOTYPE RESPONSES TO DROUGHT AND CO2 STRESSES

MODERN BREEDING, GENETIC ENGINEERING, AND BIO-TECHNOLOGIES, OFFER REMARKABLE POTENTIAL FOR IMPROVED PERFORMANCE OF STRESS TOLERANT CROP PLANTS. THESE METHODS, HOWEVER HAVE OFTEN PRODUCED PLANTS REQUIRING GREATER INPUTS OF WATER, NUTRIENTS, PEST CONTROL, ENERGY, AND MANAGEMENT COSTS. TO AVOID SUCH FALSE "IMPROVEMENTS" WILL REQUIRE TECHNIQUES TO EVALUATE BASIC PHYSIOLOGICAL STRESS RSPONSE MECHANISMS IN PLANTS, AND THUS FOCUS GENETIC EFFORTS ON SELECTION AND MODIFICATION OF THESE PHYSIOLOGICAL TRAITS. THE PROPOSED RESEARCH OBJECTIVE IS TO COMPLETE THE DEVELOPMENT OF TECHNOLOGY TO IDENTIFY AND QUANTIFY PRIMARY AND SECONDARY PHYSIOLOGICAL RESPONSES OF PLANT GENOTYPES WHICH DIFFER IN TOLERANCE TO ENVIRONMENTAL STRESS (E.G. DROUGHT AND ELEVATED CO2). SPECIFICALLY OUR EXTENDED SQUARE-WAVE, SHORT-LIVED ISOTOPE TRACER KINETICS SYSTEM AND ASSOCIATED METHODS WILL BE USED TO SIMULTANEOUSLY AND NONDESTRUCTIVELY MEASURE 10 OR MORE REAL-TIME PHYSIOLOGICAL RESPONSES TO STEP-CHANGES IN ATMOSPHERIC WATER POTENTIAL AND CHANGES IN CO2 CONCENTRATION. SENSITIVITY TESTS OF THE METHODS AND TECHNICAL DEVELOPMENTS DURING PHASE I WILL LEAD TO A PHASE II STRATEGY TO EVALUATE AND SELECT PLANT GENOTYPES FROM ONGOING CROP BREEDING PROGRAMS ON THE BASIS OF SPECIFIC PHYSIOLOGICAL TRAITS AND ATTEMPT TO PREDICT STRESS RESPONSESOF THE PROGENY. THE TESTED SPECIMENS CAN BE RETURNED TO BREEDERS OR BIOTECHNOLOGISTS FOR REPRODUCTION BY EITHER CONVENTIONAL OR ADVANCED TECHNIQUES. EVALUATION OF NEWLY EMERGING DETECTOR AND ACCELERATOR TECHNOLOGIES WILL IDENTIFYOPTIMAL COMPONENT AND DESIGN STRATEGIES FOR A PHASE III FACILITY. COMMERCIALIZATION OF THIS REFINED TECHNOLOGY WILLSERVE BOTH PRIVATE AND PUBLIC BREEDING GENETIC ENGINEERING, AND BIOTECHNOLOGY PROGRAMS AS A ROUTINE SCREENING AND EVALUATION SERVICES.