THE AGROECOSYSTEM SERVICES PROVIDED BY COVER CROPS, INCLUDING ENHANCED SOIL HEALTH, EROSION PREVENTION, CARBON SEQUESTRATION, NUTRIENT PROVISION AND PEST MANAGEMENT, ARE WIDELY RECOGNIZED. NONETHELESS, IN ARID ENVIRONMENTS THE BENEFITS RECEIVED FROM COVER CROPS MUST BE BALANCED WITH THEIR WATER CONSUMPTION. GROWERS IN THE SOUTHWEST USA DESIRE THE BENEFITS OF COVER CROPS, BUT ARE CONCERNED ABOUT THE IMPACTS OF IRRIGATION REQUIREMENTS ON ECONOMIC RETURNS. THUS, WE PROPOSE A NOVEL STUDY FOCUSING ON MINIMIZING IRRIGATION NEEDS WHILE STILL OBTAINING COVER CROP AGROECOSYSTEM SERVICES. OUR RESEARCH DESIGN WILL USE THREE COVER CROP SPECIES (GRASS [BARLEY, HORDEUM JUBATUM], LEGUME [AUSTRIAN WINTER PEA, PISUM SATIVUM] AND MUSTARD [BRASSICA RAPA, VAR. CALIENTE 199]) PLUS A THREE-WAY MIXTURE UNDER FIVE IRRIGATION REGIMES: (1) SINGLE FALL IRRIGATION AFTER PLANTING, (2) SINGLE FALL AND SPRING IRRIGATIONS, (3) SINGLE FALL IRRIGATION WITH TWO SPRING IRRIGATIONS, (4) TWO FALL IRRIGATIONS AND ONE SPRING IRRIGATION AND (5) TWO IRRIGATIONS IN BOTH FALL AND SPRING. WE WILL ASSESS IMPACTS TO SOIL ORGANIC MATTER, AGGREGATE STABILITY, AND NUTRIENT AVAILABILITY, THEREBY ADDRESSING THE AFRI PRIORITY OF, "INVESTIGATE HOW CHANGES IN PRODUCTION SYSTEM MANAGEMENT OR BIODIVERSITY AFFECT SOIL HEALTH." FURTHER, WE WILL ASSESS THE IMPACTS OF THE TREATMENTS ON THE RHIZOSPHERE MICROBIOTA, INCLUDING CHANGES TO NEMATODE, BACTERIAL AND FUNGAL COMMUNITIES, AND WILL ALSO ASSESS FUNGAL DISEASE AND WEED PRESSURE AND IMPACTS TO PRODUCTIVITY AND PROFITS; THIS WILL ADDRESS THE PRIORITY OF, "INVESTIGATE HOW PRODUCTION SYSTEMS CAN ALTER THE PLANT MICROBIOME AND DETERMINE HOW THE ALTERATIONS AFFECT PLANT RESILIENCE TO VARIOUS STRESSORS AND...AFFECT...PRODUCTIVITY."

New Mexico State University, Las Cruces NM

Investigators