Managing Irrigation in Cotton Production in Northeast Louisiana

Abstract:

Historically cotton production has been under dry-land conditions in the Mid-South.  However, increasing irrigated acres has created increased amount of irrigated cotton, especially in the Mid-South.  While irrigation management can be difficult in all cotton production systems, efficient management in the humid regions can be even more challenging.  One of the major issues is when to initiate and terminate irrigation practices.  Therefore a study was conducted in 2013 and 2014 at Winnsboro and Saint Joseph, Louisiana to determine optimum irrigation initiation and termination timings.  Three irrigation initiation (early bud, early bloom, and mid-bloom) and three irrigation termination timings (cutout+300, 400, and 500 GDD60) were evaluated.   Plot weights were used to determine yield by evaluating both seedcotton and % lint turnout.  For both locations, irrigation improved yields significantly over dry-land production systems.  However, management was different between these two systems.  Irrigation treatments did not influence cotton lint yields at the Saint Joseph location with no significant differences noted for any irrigation treatment.  Differences were found at the Winnsboro location.  Early irrigation initiation required earlier termination to result in optimum yields; however, when irrigation was initiated later in the season, later irrigation terminations were needed.  These results indicated that late season termination was the most critical factor for irrigation scheduling management in cotton production in the Mid-South.