THE GENERATION OF RENEWABLE ENERGY AND THE MANUFACTURE OF BIOBASED PRODUCTS CAN SIGNIFICANTLY REDUCE OUR GREENHOUSE GAS EMISSIONS AND BEGIN TO LIMIT THE IMPACTS OF GLOBAL CLIMATE CHANGE. BIOMASS FROM SUSTAINABLY GROWN DEDICATED ENERGY CROPS IS A KEY FEEDSTOCK FOR BIOENERGY AND BIOBASED PRODUCTS. SHRUB WILLOW (SALIX) IS EMERGING AS A SUPERIOR BIOENERGY CROP IN MANY RESPECTS, BUT ADVANCED REGIONAL BREEDING PROGRAMS TO GENERATE IMPROVED, NEW WILLOW CULTIVARS WERE INITIATED ONLY IN THE LAST TWO DECADES. INCREASING YIELD IS THE MAIN PRIORITY FOR BREEDING, BUT A MAJOR TRAIT NEEDED TO PRODUCE CONSISTENTLY HIGH YIELDS IS PEST RESISTANCE. THIS PROJECT WILL APPLY CUTTING EDGE GENETIC AND GENOMIC APPROACHES TO IMPROVE OUR UNDERSTANDING OF THE GENETIC BASIS FOR PEST RESISTANCE IN SHRUB WILLOW. WE WILL TAKE ADVANTAGE OF EXISTING TRAIT MAPPING RESOURCES TO CHARACTERIZE LOCI IN THE WILLOW GENOME THAT CONTROL PEST RESISTANCE, NUTRIENT UPTAKE, AND BIOMASS COMPOSITION AND DEVELOP MOLECULAR MARKERS FOR EARLY AND RAPID SELECTION OF IMPROVED VARIETIES. THIS PROJECT WILL IDENTIFY GENES INVOLVED IN PEST RESISTANCE IN WILLOW THAT MAY BE INTROGRESSED INTO NEW, IMPROVED WILLOW CULTIVARS THROUGH HYBRIDIZATION. WE WILL ALSO EVALUATE RECENTLY SELECTED AND PROMISING VARIETIES OF WILLOW FOR THEIR YIELD POTENTIAL IN REPLICATED TRIALS. WILLOW CULTIVARS WITH IMPROVED PEST RESISTANCE, NUTRIENT USE EFFICIENCY, AND BIOMASS PROPERTIES SHOULD RESULT IN GREATER YIELDS, WIDER ADOPTION OF WILLOW BIOENERGY CROPS, AND INCREASED PRODUCTION OF RENEWABLE ENERGY.