Yield Potential and Water Use Efficiency of Alternate Rotation Crops in the Semiarid Environment of Southwestern United States

Highlights Water use efficiency and yield potential of 10 rotation crops were tested under dryland and fully irrigated conditions. Pearl millet in grasses, cowpea and sesbania in legumes had great potential as rotation crops with greater yields and WUEs. Irrigation improved water use efficiency of crops compared to dryland conditions. Abstract. Unpredictability in weather patterns prompted a need for testing diverse crops with broad range adaptability to introduce into the existing cropping systems or to innovate alternate cropping systems in the southwestern United States. Such crops suitable for system integration should preferably be dual-purpose and resource-use efficient. Keeping this in view, a two-year study was conducted at NMSU Rex E. Kirksey Agricultural Science Center, Tucumcari, New Mexico, comprised of 10 annual crop species including grasses, legumes, and oilseed crops. The study aimed at researching yield potential and water use efficiency of the selected crops under dryland and limited irrigated conditions in the semiarid, subtropical environment. Results suggest that both crop species and water regime (irrigated vs. dryland) had significant effects on seed and biomass yield and water use efficiencies (WUE) (P