Managing Crops with Improved Irrigation Strategies: Cotton, Alfalfa Microirrigation and Furrow Studies.

Even in arid and semiarid regions where irrigation to fully meet evapotranspiration has been the preferred practice of many growers, limits in available water resources mean that high levels of water application efficiency will be required to sustain irrigated crop production, and further, that deficit irrigation practices must be considered at times for some crops.  Subsurface drip and furrow irrigated water management trials conducted with cotton and alfalfa will be discussed to identify some specific advantages and drawbacks of adjustments in water management and irrigation system choices.  Examples of situations with vegetable crops will be used to discuss other situations encountered in field irrigation trials.  Field examples will be used to show cases where increases in production or profitability associated with improved irrigation management were associated with: (1) better understanding of crop growth stages sensitive to water stress; (2) a better match of water application amounts and timing to crop water use patterns and root zone soil water storage; and (3) improved uniformity in delivery of water to the effective rooting zone.