IMPROVING THE GROWTH AND QUALITY OF CROPS IS A MAJOR GOAL OF AGRICULTURAL RESEARCH. CONSIDERABLE EFFORT HAS BEEN FOCUSED ON IMPROVING LOBLOLLY PINE TREE (PINUSTAEDA) PERFORMANCE BECAUSE IT IS THE MOST WIDELY PLANTED CROP TREE IN THE UNITED STATES. THE EFFICIENCY WITH WHICH TREES MOVE WATER FROM THE SOIL TO THEIR LEAVES (I.E., KPLANT, THE FLOW RATE OF WATER PER LEAF AREA PER PRESSURE GRADIENT BETWEEN SOIL AND LEAF) IS KNOWN TO AFFECT TREE GROWTH AND SURVIVAL, BUT IT IS UNCLEAR HOW KPLANT VARIES AMONG LOBLOLLY PINE GENOTYPES OR WHETHER KPLANT IS ASSOCIATED WITH GROWTH RATES AMONG LOBLOLLY PINE TREES. TRADITIONAL METHODS FOR MEASURING KPLANT ARE DESTRUCTIVE, ESPECIALLY FOR SMALL PLANTS, PRECLUDING THEIR REPEATED USE IN GROWTH TRIALS. THIS PROJECT WILL DEVELOP AND TEST A NOVEL, NONDESTRUCTIVE TECHNIQUE FOR MEASURING KPLANT IN LOBLOLLY PINE TREES THAT COMBINES MEASUREMENTS OF GAS EXCHANGE AND LEAF REFLECTANCE SPECTRA (I.E., THE PROPORTION OF LIGHT THAT LEAVES REFLECT AS A FUNCTION OF WAVELENGTH). IT WILL COMPARE KPLANT AMONG SEVERAL LOBLOLLY PINE GENOTYPES AT THREE GROWTH STAGES (2-, 8-, AND 18-YEAR-OLD TREES) AND TEST WHETHER KPLANT IS ASSOCIATED WITH GROWTH RATES AMONG TREES AND GENOTYPES. FURTHERMORE, IT WILL TEST WHETHER STEM BENDING ASSOCIATED WITH WIND AFFECTS KPLANT, WHICH HAS BEEN A LONGSTANDING QUESTION THAT HAS BEEN CHALLENGING TO ADDRESS WITH TRADITIONAL KPLANT MEASUREMENT TECHNIQUES. THE ULTIMATE GOALS OF THE PROJECT ARE TO TEST THE EASE AND UTILITY OF HIGH THROUGHPUT KPLANT MEASUREMENTS IN LOBLOLLY PINE IMPROVEMENT RESEARCH.