Critical Growth Stages for Water Stress in Durum, 2001

Abstract

The purpose of this research was to determine which durum growth stage is most responsive to additional irrigations (based on 35% depletion) when grown at a slightly suboptimal irrigation level of 65% plant available soil water depletion at other growth stages. A field experiment was conducted at the Maricopa Agricultural Center testing the effects of additional irrigations applied during tillering, jointing, or grain fill. Additional irrigations during tillering, jointing, grain fill, or no additional irrigations resulted in grain yields of 5964, 5419, 6301, and 4200 lbs/acre for Kronos and 5440, 5990, 5030, and 4019 lbs/acre for Westbred 881, respectively. The most responsive stage to additional irrigation was grain fill for Kronos and jointing for Westbred 881. The yield response of Kronos to additional irrigation during jointing may have been reduced by severe (78%) lodging in this treatment.