Nutrient Uptake Responses in Pima and Upland Cotton to SDI Versus Furrow Irrigation

Pima and Upland cotton cultivars were grown under subsurface drip and furrow irrigation in moderate deficit and fully-irrigated (non-stressed) treatments in a clay loam soil in California's San Joaquin Valley.  In addition, two pre-plant irrigation treatments were imposed on each of the irrigation treatments.  The two pre-plant irrigation treatments were adequate to replenish stored soil water in the upper 28 inches (low water treatment) and 62 inches (higher water treatment).  Lint yields were determined, beginning and end of season soil water contents were evaluated to allow total plant water use estimation, plant N and K uptake were evaluated at harvest timing, and samples were collected in the furrow bottoms, bed shoulders and bed centers to evaluate treatment impacts on root length density.