Irrigation Scheduling Based on the Crop Water Stress Index and Precision Water Application for High Cotton Yield

Abstract

A modified, low- pressure linear move irrigation system was used to irrigate cotton at the Marana Agricultural Center, University of Arizona in 1985. Irrigations were scheduled using the Crop Water Stress Index (CWSI) for timing and a neutron probe to determine soil moisture deficits. Irrigations were applied when the CWSI reached 0.1 resulting in minimal seasonal water stress. Yields ranged from 3.14 bales /acre to 2.73 bales/acre from 2 acre plots. Total applied water ranged from 31.3 inches to 32.3. Total seasonal rainfall was 2.90 inches.