Project Number: 6208-13000-006-00
Project Type: Appropriated

Start Date: Dec 22, 2006
End Date: Dec 21, 2011

Objective:
1. Develop new tools and a knowledge base that will enable decision makers to more effectively manage and conserve water resources. 1.a Design and test sensors that will quantify the level of plant water stress in growing crops and can be used to make irrigation decisions. 1.b Determine the relationship between crop productivity and applied water as a function of environmental factors so that irrigation can be managed for optimal use of all available water. 2. Develop and evaluate techniques and methodologies that maintain efficient agricultural production under deficit irrigation and dryland production. 2.a Design and evaluate water management strategies that optimize water use and crop production with limited well capacity. 2.b Define and evaluate crop management systems to facilitate the transition from irrigated to dryland cropping, considering crop species and varieties, cultural practices, and that incorporate long range weather prediction. 3. Identify changes in soil microbial, chemical, and physical properties affecting soil water availability and develop management practices that impact soil properties to sustain and improve crop production where water supply is in transition from limited irrigation to rainfed production. 4. Develop Best Management Practices based on a growing region's climate variability. 4.a Develop optimal planting strategies that integrate seasonal climate forecast information into agricultural managment. 4.b Develop software tools that provide detailed knowledge of precipitation, temperature stress, and evapotranspiration and demand to producers and plant breeders.

Approach:
Develop and evaluate techniques and methodologies that utilize limited water resources efficiently to maintain economically viable deficit irrigated and dryland agricultural production systems. Develop new approaches, including acoustic detection of xylem cavitation and portable chamber technologies, to quantify the degree of crop drought stress and evaluate new and existing deficit irrigation strategies. Examine irrigation quantity and application rate effects on water use efficiency using the BIOTIC protocol for irrigation scheduling. Explore the efficiency of subsurface drip irrigation for storing water from low capacity wells in the soil during the fallow season. Determine the feasibility of enhancing water infiltration with adapted grasses and use water stored in playa lakes for forage production. Evaluate new crop species and cultural practices for facilitating the transition from irrigated to dryland cropping systems. Determine the effects of crop rotations and residue management systems on soil microbial, chemical, and physical properties including effects on soil water availability, infiltration, and rainfall capture efficiency. Assess the influence of row spacing and planting patterns on water use efficiency of different cropping systems. Use seasonal climate forecasts to develop optimal planting strategies and software tools to provide detailed predictions of precipitation, temperature stress, and evapotranspiration demand for producers and plant breeders. This multifaceted research program will provide the knowledge base for optimizing the use of scarce water resources especially in arid and semi-arid regions where ground water resources are being depleted.