CROPS REGULARLY FACE SIMULTANEOUS ATTACK BY BOTH ABOVE- AND BELOWGROUND HERBIVORES. TWO OF THE MOST COMMON PEST GROUPS ARE PLANT-FEEDING NEMATODES AND INSECT HERBIVORES. PLANTS UTILIZE A BROAD RANGE OF DEFENSIVE COMPOUNDS TO DEFEND AGAINST HERBIVORES ABOVE AND BELOWGROUND; NEMATODES ARE KNOWN TO ALTER PLANT DEFENSIVE CHEMISTRY, BOTH INTERNALLY AND THROUGH VOLATILE SIGNALS, AS WELL AS PLANT NUTRITION. INSECT HERBIVORES CAN RESPOND TO THIS VARIATION IN QUALITY, WHICH INFLUENCES HOST CHOICE OF LARVAE AS WELL AS ADULTS. FEEDING BY INSECT HERBIVORES ALSO CHANGES PLANT DEFENSE QUANTITATIVELY AND QUALITATIVELY, WITHIN THE PLANT AND THROUGH VOLATILE SIGNALS THAT ATTRACT PREDATORS.ACCORDING TO REVIEWS, NEMATODE-INSECT INTERACTIONS ARE VARIABLE DEPENDING ON THE SYSTEM BEING STUDIED AND UNDERLYING MECHANISMS ARE STILL LARGELY UNKNOWN. ALTERING INPUTS SUCH AS FERTILIZATION CAN ALSO PLANT CHEMICAL DEFENSE AND ABILITY TO RESPOND TO PESTS, AS WELL AS CHANGE INTERACTIONS BETWEEN PREDATORS AND PESTS,ALTERING THE OUTCOME OF ABOVEGROUND-BELOWGROUND INTERACTIONS. SOME OF THESE FACTORS ARE WITHIN THE GROWER'S CONTROL, AND UNDERSTANDING HOW THEY IMPACT OUTCOMES COULD ALLOW FOR THE DESIGN OF BETTER MANAGEMENT STRATEGIES FOR ABOVEGROUND-BELOWGROUND PESTS WITHOUT THE USE OF PROPHYLACTIC PESTICIDES.THE GOAL OF THISRESEARCH IS TO UNDERSTAND HOW PLANT-MEDIATED INTERACTIONS BETWEEN PLANT PARASITIC NEMATODES AND INSECTS INFLUENCE PEST AND NATURAL ENEMY ATTRACTION AND FORAGING SUCCESS. I WILL USE A COMBINATION OF FIELD AND LABORATORY EXPERIMENTS TO DETERMINE WHAT FACTORS ALTER THE OUTCOMES OF THESE INTERACTIONS TO CREATE BETTER PEST MANAGEMENT STRATEGIES THAT INCORPORATE ABOVE- AND BELOWGROUND PESTS.MY RESEARCH WILL FOCUS ON TWO MAIN QUESTIONS: FIRST, HOW DOES FERTILIZATION ALTER PLANT-MEDIATED NEMATODE-INSECT INTERACTIONS? FERTILIZATION HAS DIRECT IMPACTS ON PLANT GROWTH AND DEFENSE, WHICH THEN INDIRECTLY INFLUENCE PLANT-MEDIATED INTERACTIONS. FOR EXAMPLE, A WELL-FERTILIZED PLANT IS A BETTER HOST FOR MOST HERBIVORES, BUT SOME FERTILIZERS SUCH AS CHICKEN MANURE COMPOST AND VERMICOMPOST CAN REDUCE NEMATODE POPULATIONS.SECOND,HOW DO PLANT-MEDIATED INTERACTIONS BETWEEN NEMATODES AND INSECT HERBIVORES INFLUENCE PREDATOR ATTRACTION AND FORAGING SUCCESS?BOTH NEMATODES AND INSECT HERBIVORES INDEPENDENTLY ALTER PLANT CHEMISTRY, SUCH AS VOLATILE ORGANIC COMPOUNDS, WHICH ARE KNOWN TO INFLUENCE PREDATOR FORAGING. LITTLE IS KNOWN ABOUT THE EFFECT ON GENERALIST PREDATORS IN THE FIELD, WHICH ARE CRITICAL FOR PEST CONTROL IN MANY AGROECOSYSTEMS INCLUDING POTATO. I WILL ANSWER THESE QUESTIONS USING MANIPULATIVE EXPERIMENTS THAT COMBINE CHEMICAL ECOLOGY WITH PLANT, INSECT, AND NEMATODE RESPONSES, AND USE THE RESULTING INFORMATION TO 1) CREATE AN ECOLOGICAL TEMPLATE FOR NEMATODE-BEETLE INTERACTIONS THAT WILL HELP GUIDE FURTHER RESEARCH ON THE TOPIC; AND 2) CREATE A MANAGEMENT FACT SHEET FOR GROWERS WHO MUST MANAGE ABOVE- AND BELOWGROUND PESTS IN THEIR SYSTEMS, PROVIDING THEM WITH INFORMATION ABOUT WHAT TYPES OF SOIL AMENDMENTS AND NATURAL ENEMY PROMOTION STRATEGIES MIGHT BE BENEFICIAL FOR THEM.