** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** GLOBAL CROP YIELDS ARE ESTIMATED TO DECLINE ABOUT 20-30% PER YEAR BECAUSE OF PLANT PESTS AND PATHOGENS, THREATENING WORLDWIDE FOOD SECURITY. PLANT-PARASITIC NEMATODES (PPNS) REPRESENT PARTICULARLY PERNICIOUS PATHOGENS RESPONSIBLE FOR CAUSING CROP LOSSES EXCEEDING $100 BILLION ANNUALLY. FARMERS EMPLOY DIVERSE STRATEGIES TO MITIGATE NEMATODE DAMAGE. THESE APPROACHES INCLUDE CROP ROTATION, SOIL STERILIZATION USING PLASTIC COVERINGS, AND THE CULTIVATION OF NEMATODE-RESISTANT CROP VARIETIES, ALL OF WHICH CONTRIBUTE TO MANAGING THE ISSUE. HOWEVER, THE MOST POTENT AND EFFICIENT SOLUTION REMAINS THE APPLICATION OF PESTICIDES TO TREAT FIELDS. FOR DECADES, SYNTHETIC NEMATICIDES HAVE BEEN PIVOTAL IN MANAGING PPNS, BUT LEGITIMATE CONCERNS REGARDING THEIR ENVIRONMENTAL TOXICITY AND HUMAN SAFETY HAVE LED TO JUSTIFIED BANS ON MOST USED NEMATICIDES. FOR EXAMPLE, OXAMYL, A SYSTEMIC COMPOUND WITH BASIPETAL TRANSLOCATION PROPERTIES, STANDS AS THE SOLE COMMERCIALLY AVAILABLE PRODUCT UTILIZED FOR FOLIAR TREATMENT. HOWEVER, ITS USE AS A LIQUID FORMULATION IS RESTRICTED IN MANY COUNTRIES DUE TO CONCERNS RELATED TO TOXICITY. THIS HAS RESULTED IN A GLARING SCARCITY OF EFFECTIVE AGENTS FOR PPN CONTROL. OUT OF THE 20 KEY NEMATICIDES UTILIZED DURING THE TWENTIETH CENTURY, ONLY 4 PRESENTLY HOLD APPROVAL FOR USE IN THE EUROPEAN UNION, WITH A MERE 3 AVAILABLE IN THE USA WITHOUT CONSTRAINTS. WHILE THESE REGULATORY ACTIONS ARE WARRANTED, THEY HAVE LEFT FARMERS WITH LIMITED OPTIONS AND NO VIABLE MEANS OF CONTROLLING NUMEROUS PPNS. IN THIS PROPOSED STUDY, ECONOMICALLY IMPORTANT POTATO CYST NEMATODE (PCN) GLOBODERA PALLIDAIS SELECTED AS OUR TARGET CONTROL TO MANAGE CROP HEALTH AND MAXIMIZE YIELDS. G. PALLIDAIS A GLOBALLY REGULATED PEST OF POTATO (SOLANUM TUBEROSUM) AND IS OF GREAT ECONOMIC IMPORTANCE IN MANY COUNTRIES THROUGHOUT THE WORLD. IT IS A QUARANTINE PEST IN THE STATE OF IDAHO WHERE IT WAS DETECTED IN 2006. G. PALLIDAIS A HIGHLY SPECIALIZED OBLIGATE ENDOPARASITIC NEMATODE THAT REQUIRES A LIVING POTATO PLANT AS A HOST TO COMPLETE ITS LIFE CYCLE. IN HIGHLY INFESTED FIELDS, THE NEMATODE CAN REDUCE TUBER YIELDS UP TO 80% AND IS SPREAD MAINLY THROUGH THE MOVEMENT OF SOIL, TUBERS, OR FARM EQUIPMENT. SIGNIFICANTLY, NOT ONLY DOES PCN CAUSE MAJOR YIELD LOSSES IN POTATO INDUSTRY, PCN-INFESTED AND SURROUNDING FIELDS ARE REGULATED BY USDA-APHIS AND ISDA. CONTROL OF SOIL-BORNE PESTS AND DISEASES HAS TRADITIONALLY BEEN ACCOMPLISHED BY SOIL FUMIGATION. THE MOST WIDELY USED COMPOUND HAS BEEN VOLATILE METHYL BROMIDE WHICH IS TOXIC AND HAS BEEN PHASED OUT AS A CLASS 1 OZONE DEPLETING SUBSTANCE UNDER THE MONTREAL PROTOCOL (HTTPS://WWW.EPA.GOV/ODS-PHASEOUT/METHYL-BROMIDE). INFESTED FIELDS ARE NOW BEING FUMIGATED WITH THE LESS EFFECTIVE SOIL FUMIGANT, TELONE. HENCE, THERE IS AN URGENT NEED TO DEVELOP NEW CLASSES OF NEMATICIDES WITH NOVEL BIOACTIVITY, THAT ARE EFFECTIVE WHETHER APPLIED TO SOIL OR DIRECTLY TO CROPS, WHILE REMAINING ENVIRONMENTALLY BENIGN AND SPECIFICALLY DESIGNED TO TARGET THE IN,TENDED PESTS.NEMATODES GENERATE A DISTINCTIVE, EVOLUTIONARILY CONSERVED GROUP OF PHEROMONES KNOWN AS ASCAROSIDES. THESE SIGNALING MOLECULES PLAY PIVOTAL ROLES IN ORCHESTRATING NEMATODE'S DEVELOPMENTAL PROCESSES AND FACILITATE COMMUNICATION BOTH WITHIN NEMATODE'S OWN COMMUNITY AND WITH OTHER ORGANISMS. ASCAROSIDES ARE THE DERIVATIVES OF DIDEOXY SUGAR ASCARYLOSE, UNDERGOING COMBINATIONS WITH DIVERSE LIPOPHILIC SIDE CHAINS DERIVED FROM FATTY ACIDS AND OTHER MOIETIES ORIGINATING FROM PRIMARY METABOLISM. IT HAS BEEN REPORTEDTHAT ASCAROSIDE ASCR#18 ACTING AS A PATHOGEN-ASSOCIATED MOLECULAR PATTERN (PAMP) TRIGGERS PLANTDEFENSE MECHANISM INCLUDING ACTIVATION OF (A) MITOGEN-ACTIVATED PROTEIN KINASES, (B) SALICYLIC ACID- AND JASMONIC ACID-MEDIATED SIGNALING PATHWAYS, AND (C) DEFENSE GENE EXPRESSION. MOREOVER, THE PLANT INNATE IMMUNITY ELICITED BY ASCR#18 OFFERS COMPREHENSIVE PROTECTION AGAINST A BROAD SPECTRUM OF PATHOGENS. ASCAROSIDE PHEROMONES ALSO PLAY A SIGNIFICANT ROLE IN THE CHEMOTAXIS BEHAVIOR OF NEMATODES, PARTICULARLY IN THEIR RESPONSE TO ENVIRONMENTAL CUES AND INTERACTIONS WITH OTHER ORGANISMS. DIFFERENT ASCAROSIDES CAN HAVE BOTH ATTRACTANT AND REPELLENT EFFECTS ON NEMATODES, DEPENDING ON THEIR CONCENTRATION AND THE SPECIFIC ASCAROSIDE INVOLVED. SOME ASCAROSIDES ATTRACT NEMATODES TOWARDS FAVORABLE CONDITIONS, SUCH AS AREAS RICH IN FOOD SOURCES, WHILE OTHERS CAN REPEL THEM FROM UNFAVORABLE ENVIRONMENTS OR DETER THEM FROM POTENTIAL THREATS.CONVENTIONAL PESTICIDES OFTEN ENTER THE ENVIRONMENT THROUGH PROCESSES SUCH AS LEACHING, VOLATILIZATION, AND RAINWATER RUNOFF, LEADING TO A NOTABLE REDUCTION IN THEIR EFFECTIVENESS. THIS LOSS OF PESTICIDES HAS SIGNIFICANT ADVERSE EFFECTS ON ECOSYSTEMS AND POSES HEALTH HAZARDS TO HUMANS. THEREFORE, THE DEVELOPMENT OF INNOVATIVE TECHNOLOGIES TO MITIGATE PESTICIDE LOSSES, IMPROVE UTILIZATION EFFICIENCY, AND REDUCE ASSOCIATED POLLUTION IS OF PARAMOUNT IMPORTANCE. IN RECENT YEARS, A RANGE OF SLOW-RELEASE PESTICIDES HAS EMERGED, UTILIZING TECHNOLOGIES SUCH AS MICROCAPSULES, MICRO/NANO COMPOSITES, AND ORGANOSILICONE. WHILE THESE INNOVATIONS HAVE MANAGED TO REDUCE LOSSES AND ENHANCE PESTICIDE UTILIZATION EFFICIENCY TO SOME DEGREE, PRECISE CONTROL OF THEIR RELEASE TO MEET CROP REQUIREMENTS AND SIGNIFICANTLY BOOST OVERALL UTILIZATION EFFICIENCY HAS PROVEN CHALLENGING. THIS LIMITATION HAS HINDERED THEIR WIDESPREAD ADOPTION. CONSEQUENTLY, THE DEVELOPMENT OF CONTROLLED-RELEASE PESTICIDES HAS BECOME A FOCAL POINT IN BOTH AGRICULTURAL AND ENVIRONMENTAL FIELDS.HISTORICALLY, CONVENTIONAL SYNTHETIC HYDROGELS TYPICALLY MADE FROM ACRYLIC AND POLYACRYLAMIDE MATERIALS WERE UTILIZED IN AGRICULTURE. NEVERTHELESS, THEIR LACK OF BIODEGRADABILITY RAISED CONCERNS ABOUT POTENTIAL POLLUTION. ADDITIONALLY, THE GRADUAL BREAKDOWN OF SYNTHETIC POLYMERS IN AGRICULTURAL APPLICATIONS COULD NEGATIVELY IMPACT SOIL FERTILITY. GIVEN THE GROWING EMPHASIS ON ENVIRONMENTAL ISSUES, BIODEGRADABLE HYDROGELS HAVE GAINED PREFERENCE OVER THEIR SYNTHETIC C,OUNTERPARTS IN CERTAIN SITUATIONS. BIODEGRADABLE HYDROGELS OFFER ADVANTAGES DUE TO THEIR RENEWABILITY, BIOCOMPATIBILITY, AND NON-TOXIC PROPERTIES, MAKING THEM AN APPEALING CHOICE FOR AGRICULTURAL PURPOSES SUCH AS MOISTURE RETENTIONAND PEST CONTROL.POLY-Γ-GLUTAMIC ACID (Γ-PGA), INITIALLY IDENTIFIED IN BACILLUS ANTHRACIS, IS A NATURALLY OCCURRING BIOPOLYMER COMPOSED OF GLUTAMIC ACID MONOMERS LINKED BY AMIDE BONDS BETWEEN Γ-CARBOXYLIC ACID GROUPS. Γ-PGA HAS GARNERED CONSIDERABLE INTEREST FOR ITS VERSATILE APPLICATIONS IN THE MEDICAL, AGRICULTURAL, AND FOOD SECTORS, OWING TO ITS UNIQUE ATTRIBUTES OF BIOCOMPATIBILITY, BIODEGRADABILITY, AND WATER SOLUBILITY.Γ-PGA HYDROGELS FEATURE A THREE-DIMENSIONAL NETWORK STRUCTURE CAPABLE OF ABSORBING SUBSTANTIAL AMOUNTS OF WATER AND EXPANDING IN VOLUME WITHOUT DISSOLUTION. CONSEQUENTLY, THEY HOLD PROMISE AS DELIVERY SYSTEMS, NOT ONLY FOR CONTROLLED PESTICIDE RELEASE BUT ALSO FOR WATER CONSERVATION IN AGRICULTURAL SETTINGS, SUCH AS MITIGATING WATER LOSS THROUGH SURFACE EVAPORATION AND FACILITATING REHYDRATION VIA IRRIGATION OR RAINFALL. FOR THIS PROPOSED STUDY, WE INTEND TO DEVELOP LIGHT-RESPONSIVE Γ-PGA BASED HYDROGELS FOR CONTROLLED NEMATICIDE DELIVERY.

Regents Of The University Of Idaho, Moscow ID

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